Well, you can TALK to a nearby engineer and see if they will review this video and give you their ESSPURT opinion.. Or look at what all is being shown, build one of the trusses yourself, and test the theory with weights. Just don't stand directly under it when adding weight.
When someone says "I am an Engineer," it is just like someone announcing that "I am a Lawyer." An engineer has to complete a formal course of study in a recognized engineering discipline. The BIG three disciplines are Mechanical, Electrical, and Civil. Nearly every other discipline falls under the umbrella of study of those three categories. Once the degree has been bestowed upon the individual, they then have to look up their state's professional examination requirements to become an engineer. Some states are easier than others, meaning that if you hold a degree and pay the fee, you are an engineer. However, nearly every state has some exam requirement as well as a period of training under a Professional Engineer (PE). Once those requirements are met and fees have been paid, that individual may call themselves an "Engineer."
I did exactly this and increase my height from 2400mm to 3200mm for an almost cathedral style ceiling!! Nice work on calculations I did the old school engineering where I slapped it and said “that’s not going anywhere”
Fellow engineer here, I can't tell you how excited I am about finding this, as well as all the details and info you show. Great job! I have the same ceiling height and trusses in my 30'x72' pole barn and am wanting to do this! I have a 4 post lift coming and would love an extra 3 feet of lifting height!
@@chinocool7481 I wrote this a year ago!?!! Man, I ummm, yeah need to get on this. I haven’t done it yet. Haha. My brother (super nerd, chemical engineer) modeled my roof and current trusses in cad. Then we sent it and our new design to our retired mechanical engineer friend that loves doing structural analysis. He gave us mountains of data. Spreadsheets. Drawing sketches. I put the project on hold to put flooring in my house, paint, and new trim. Gotta keep the wife happy. Then I’ve been insulating and wiring additional outlets in my pole barn. Hopefully in spring or early summer I’ll get to it.
Hi, can you share some information from the mechanical engineer roof report? I'd comment on this video, but the guy owning the channel doesn't respond it seems like. I have feedback about the process. I'm a building inspector and woodworker. Install collar ties, a horizontal board through the truss. And put in strong back truss bracing. Basically a continuous board perpendicular to the trusses to prevent deflection sideways. Last, a double bottom cord is a good idea. This video did a great job, but hopefully some people see my three recommendations to make it much better. I'd probably install a ledger or double ledger at the side wall too.
FYI for those of you who might have more clearance for a lift but want to keep your standard garage door; you can special order angled horizontal garage door tracks to accommodate for more space for a lift. I did that a few times when I had a small garage door business for customers. Much cheaper than a new roll up door.
@@samerickson89 try to find a garage door supplier in your area, or talk to some smaller garage door repair places that might want to entertain the hunt. The rails were special order from the supplier to the manufacturer. It's not as crazy as it sounds. Mention high lift tracks
You’ll need different drums, longer cables, different spring(s) and side mount opener. Tell your local garage door company you want a high lift track set up for your door.
Thank you very much for the comment Jacob! I have been thinking about doing a video on this series and going more in depth with the calculations involved
@@EnigmaEngineering didn’t think you could top this, but here you come again :) I’m trying to use this method to vault the ceilings in my PNW rancher. I messaged you on IG, any help is greatly appreciated 🙏🏽
I'm a professional mechanic who runs an auto repair business out of my home. I desperately need a lift in my garage but have 8ft ceilings. Id love an extra foot or two. My attick sits above the garage so this may be a challenge. Your comment about moving the garage opener to the side was a good nugget. Either way it's good to see there's somebody out there in my same predicament. Wish I had the engineering skills you do.
Thanks for the comment Josh! This is going to sound crazy, but one method I heard from a few people is to run wood beams through the existing trusses, then rent a crane, connect it to the beams, and pick the roof off the garage (after cutting around the perimeter to free everything up). Then you would add an extra 2 ft+ of framing/siding and put the roof back on. It would save you from having to re-roof, modify trusses, etc.
Wish I would have been more dedicated in mechanical engineering class now Edit: honestly if you could make a video where you guide through the calculations so I could do this to mine safely that'd be awesome. I'm an electrical engineer so I could definitely follow along. Thanks for considering ✌️
Great idea using it. Also instead of the rolled if you want more R value, you can modify the track to run the angle of your new roof line, harder angle up instead of out. Neighbor just did in pole barn.
I've been thinking about doing this to my house roof for a couple years. I've talked with several contractors and they tell the same thing. Have to use a LVL or steel beam. I'm not buying it. I like what you did. Thanks for sharing your knowledge.
Hey Ray! No problem. Obviously I can't tell you exactly what to do with your build. But, the safety factor of trusses you can buy at a hardware store is generally pretty high (like ~7-10). My recommendation is finding a truss style that gives you the extra vertical room, then perhaps increasing the number of trusses like we did. For example, a scissors truss is weaker than a traditional truss. So, we doubled the # of trusses to approximately match the safety factor.
I have a similar truss situation. My plan is to cut all the sheeting and end fasting nails of the trusses that I'll be moving using a sawzall and once clear of all nails I'll slide the middle trusses away from center and against the outer trusses nailing them together to create a form of girder truss on each side of the bay. At that point I will span the 12' gap with structural 2X6s on 16" centers between the two "girder" trusses using joist hangers on each end of the 2X6 purlins to support the roof sheeting. This method opens the bay giving the maximum height possible while retaining the integrity of the structure.
i put a mid rise lift in my single car garage last week, it hit one ceiling joist, so i converted that one joist into scissor joist using mostly aLL the wood already in place, no need to over engineer things. IT took me just over 2 HRS. up in north maine we get high snow loads but i installed a metal roof 4 yrs ago which gets rid of snow.
I'm here because an associate of mine removed his garage rafters and it left him with a HUGE amount of overhead space. I asked him "Don't you need those to maintain the structural integritiy of the garage? He just said "naw my garage is fine. Strong as ever. ". I have been chewing on doing mine every since. But the kicker is I DYI'ed an 18' addition to turn my 2 car into a 4 car years ago and I added the rafters because I thought they held the walls against the outwardly pressure of the A-frame pushing down . I didn't need gables .
My garage is my woodshop, and the ceilings are exactly 8' tall, which is often a problem when you factor in shop lights dangling 8-10" below that. I'm considering this as a future project... I am a Landscape Architect, but I work in a civil engineering firm with structural guys so between this video and them, I'm confident I could pull it off. Thanks brother.
Great vid and thanks for sharing. This is exactly the project I've been pulling my hair out on having completed. Other than the engineering side of this project, I am capable of completing the work. My problem is several structural engineers won't advise or won't design for me. I just need the blueprint and specs. I can take it from there. You ever think of setting me up with a safe design based on my setup. I do have the original blueprints from the house built in '89.
Hey, thanks for the comment! More videos on the garage build to come. Regarding the design, I wouldn't advising you on your setup. I want everyone to have a super garage. The easiest way is probably finding me on instagram and PM'ing me: enigmaengineering
I need modify my roof high, I'll follow your method, I wait to find the kind screw that you used in my country but maybe I can to use someone similar in weight resistance or reforcer joins with iron plates, thanks for you time and excellent job.
Great Job, I'm about to do the same thing, that is how i found the video. This is very overbuilt, which is good. It seems you used Doug Fir instead of yellow pine. Doug Fir isn't supposed to be used in a joist / rafter type situation. Usually for studs only. Doug fir is much easier to work with though and in the end won't make a difference given how overbuilt this is. You could have also scabbed osb to the side of the Scissor truss after adding another 2x6 to even the thickness instead of adding another truss inbetween. If you do this method the OSB should be nailed or stapled every 6"s or so
What is the spand of your trusses? and what size timber did you use? Also what snow payload did you calculate for? 1kn/m2? and are your trusses spaced 3 feet apart? What is the roof pitch and what are your ceiling pitch? They should be 10-15 degrees different depending on the slope of the roof.
I'm doing a single bay in my garage where my 2 post lift is but installing a ridge beam that'll be supported by the post of the car lift. Just gonna cut out all that mess.
@@EnigmaEngineering Goodluck! It took me 5+ years to find mine and I got lucky! I saw a rusted out frame of a 70 cuda missing hood, every door panel dinged, floor pans rusted out, no engine, transmission, wiring and the "car" sold for 20k...people are out of their minds when it comes to ebody cudas.
Thats why Engineers aren't allowed on the jobsite.... standing on the top of the ladder. :) Very cool, and wish more Engineers had to be occasionally TDA'd to their respective jobsites to see how the things they engineer actually are built, and how crazy some of their ideas are. I'm looking at you Nissan engineers, 2 hour job to replace spark pliugs.
Honda was no different, wanna change a starter or Ac compressor in a civic? Pull the engine. :-/ Next to the lawyers, the enginerds would be the next bus off the cliff.
How do you like new garage door and opener? Wondering what that looks like, and if you plan on changing other larger garage door to match exterior look and style of new garage door? Peace
I have those trusses in 2x6 in my barn. I want to install a ceiling hoist across the trusses. First I installed grade 8 bolts on the center triangle and am installing cross 2x6 blocking starting from the front header. My lift weight on the hoist will be about 500 pounds, normally much less, on a 20 foot track bolted to the trusses with grade 8 bolts. Are the trusses able to handle the lifting weight?
Great video- thinking about the same for my 24 x 24 garage in NC but to get the necessary extra room for a golf simulator. You did't mention the span of the garage. And did you consider using engineered wood for added strength and rigidity? I am not an engineer but get the impression LSL or LVL timbers would have allowed not doubling the trusses. In any case very nice job!
Hi David, thanks for the comment! You are not alone on the golf simulator. The span was 23 feet in this example. We didn't consider engineered wood simply due to cost. But microllam or parallam would be great for this job. You likely would not have to double up the trusses either. I probably did not have to - I just wanted to match the original safety factor identically and I had never seen anyone else do this so was being extra cautious. Also - add in some collar ties for extra beef
I just need to get 6 inches in my double garage 5 trusses to modify so I can swing get a driver for my golf simulator. Is there a simple way of do this I am a carpenter here in Toronto and I loved your videos. John
I'm actually in the middle of starting this to my garage right now. Can you tell me what fasteners, or ties you used at the top plates at the end of the truss on top of the existing wall? Maybe I missed it.
I’m wanting to do this in my barn at home but it’s 30’ wide how do I figure up how long of boards I need? And how far down do you bolt the boards from the peak was that 3.5’ ft?
Hi Nick - you would want someone on a ladder to help you pull a tape measure for the exact dimension. We went down 2'-5" from the inside peak - but the more you get here (i.e., larger distance), the stronger the scissors will be.
But is it to code? Did you get a permit? If you sell the house... will it be an issue? I know if I walked into the garage and saw that.... I would question if it was to code.
Not a lot of codes exist for non-dwelling structures like sheds and garages in my home state. Never selling the house. But, definitely would be a slight concern otherwise. Generally our basement foundations are collapsing which is a bigger issue
You sound like a scared little man. He created a professional looking modification, this isn't some yahoo with a few scrap 2x, elmer's glue and a nail gun.
Thanks! We are just across the lake from you (unless you are UP). Google search "snow loads by state" and see where you are on the chart. We used 60 lbs/ft^2 to be safe and were well under the safety factor (i.e., less than 10% of the roof strength at full snow and wind load)
High there I am from bc Canada. I have a hoist in my garage currently with an 11 foot ceiling. The peak runs the same as your garage project. I already have a side mount opener and the tracks rammed basically right to the roof. I have plenty of room in the attic above the garage to do the same idea.
Hi Yassir. They have been 100% solid. At one point last season there was ~2 feet of snow/ice on the roof; the drywall has no visible cracks - no evidence of any movement
I need to do this also... my peak is 90 deg. from yours... how do I figure out the angle needed for the new tuss? my building is 28x32 the peak is on the long 32 front to back.
Hi Daver. Measure the distance to the peak of your garage. Then use something like google sketchup (free) to draw out the truss. Or send an email and we can help out: enigmaengineeringllc@gmail.com
Thanks for doing this. Do you have any sense of whether there’s a version of this that can be done in Florida, where our houses have to meet code for hurricanes? (I think they need to withstand something like 150 mph winds.)
Thanks for the comment! I think a similar strategy should work in FL. I am from the Midwest and I think used 60 lbf/ft^2 for my combined "dead" and "live" loads accommodating 2 feet of snow + winds . Just a quick search showed 15 lbf/ft^2 dead load in Florida and at least a 30 lbf/ft^2 live load, so minimum 45 lbf/ft^2. But, an equation for wind force is P = .00256 * (Velocity)^2. At 120 MPH, P = 37 lbf/ft^2, so 37+15 = 52 lbf/ft^2 total load. But, to be safe, 150 MPH sustained wind speed would be P = 58 lbf/ft^2, so 73 lbf/ft^2 total load - this would be a very strong roof. Let me know if you want more thoughts!
This video is amazing. Can you kindly tell me all the steps one by one in written which you told on videos, so I can even write an article on it? Thank you!
Dude! Great video. I so wish you were a little farther south so you could be my Structural engineer in west chicago suburbs. I have the same issue but unfortunately have bobtail trusses on a hip roof garage. I am pretty sure that I could do it but I do not have the degree or certification to convince the municipality.
Thanks! Good question. The mending plate bottom edge on our original trusses did not come down below the the wood, so we had no issues with the king post. We did have to notch a few rafter ties with a grinding wheel and sawzall though. I suppose you might be able to do the same to a mending plate, then add new plates to the existing wood. We used structural screws with nail plates in a few places
Any idea what I should expect to pay a structural engineer to design something for me? Would this be something I could hire you for if I send you any and all dimensions? I took CAD in highschool and could easily send you something from SketchUp or something in isometric or front/side drawings
Hi Paul! It would not be that expensive - in the hundreds. I have helped a few people out with this (PE mechanical), send an email if you want: enigmaengineeringllc@gmail.com
great idea and job!!! I need to do the same in my garage... my peak runs the other way 90 off your garage, so I would need to do the entire garage's trusses. did you do yours only because you needed one bay for working under the cars? what do you think the downside if any of doing the entire garage (other than cost and work LOL) Im doing a 4 post for 90% storage rather than work. I live in southern Cal so no snow load issues - just Spanish tile (fire protection) roof which heavy thanks if you reply
I want to remove the drywall from my garage ceiling. I plan on adding storage shelves to existing trusses so I can access easily all around the garage instead of crawling though my 4x4 opening. What is the pros and cons to doing this?
did you ever consider adding the scissor trusses next to the original trusses and marring them to the original trusses? the only hurdle might be how the hold the truss ends. unless ledger boards might work to push up under the scissor truss after it has been married tot eh original truss. then cut out the un needed original truss.
My garage is very similar in construction and I've been looking for ideas to do the se thing for my lift. Funnily enough my S5 is one of the vehicle going on the lift so I laughed when there was an S5 at the start of the video. What was the roof pitch of the existing garage?
Thank you for sharing your work. I am in the process of rebuilding/re-designing my garage and I would love to use that design. Let me ask you about the size of the world you are using. Is this 2 x 8? Or just 2 x 6?
Why can't truss manufacturers supply the right kind of truss to sister to your truss with the gussets not completed so you have 2 halves that could easily be lifted in place then rent a press to complete the 3 or so joint plates. Seems like a reasonable DIY solution to modify in place. Fasten old truss to new everywhere practical. Then cut the stringers of the old truss to the bottom level of the new truss. This solution in the video is great too but an inspector is unlikely to pass it if they can even get to it to see it. Curious if you can do an update on the condition, any cracks in the drywall should be a good indicator of movement.
This will sound slightly crazy, but probably the easiest way for that style of roof is to lift the roof up with some jacks and then add a new section of studs around the perimeter of the gap at the top plate - I would have done that here but then my garage would have been outside of local building height codes
Any chance could give a little advice off a picture? Morton building wanting to remove lower chord so can walk on the top of the built office spaces. So thinking of adding posts to truss to office walls on both sides of space then remove center lower chords. Basically extend the wall to upper roof chord and tie in the rest of the y sections back into 2x8 supports on 3 trusses. Making walking space into the attic space. If up to a little advice or opinion reply and I’ll give email. Thanks
Question for you...what kind of pitch did you have on the current roof? My roof is a 12/12 pitch with 8' walls. That being said, i could possibly even get a little more ceiling height over boxed in areas? Plan on storing a car on and under left. Am going to do this to garage just completing. I've already had my framing inspections and am awaiting my electrical then I can do my magic. Plan on reaching out if that's ok. Thanks for the video, Les.
Hey Les. Thank you for the question! My roof pitch is 8/12. The biggest advantage of 12/12 is the availability of a horizontal collar tie below the king post that would greatly increase the strength of a modified truss in your case, while still give you plenty of overhead space. I would have to see a sketch of your roof and where you are meaning to store cars to answer your question. My email is in the contact info on our website, feel free to reach out! enigmaengineeringllc.com/
Are those trusses 8 in on Center? Holy mackerel. You could drive a tank over that roof. I just took my top of my trusses and I screwed plywood to them and it made my roof so stiff you could break your ankles walking around up there. Your roof is probably stronger than mine
So, you added what, (20), 20' 2"x6"s, (10) 18" verticle struts, (60)+ nut and bolt assemblies for a total of roughly 400-500#s? Did you add any upright supports to the top plate studs?
That sounds close to the weight we added to the roof. I calculated the strength in the 2x4 studs to check the general magnitude. But, I kept in mind that a fully-loaded 62 lbf/ft^2 roof would be over 50,000 lbs, so the 400-500 lbs didn't concern me too much. The additional weight over the garage door header was a larger concern (ended up fine on this). There is a lot here - at one point I thought about going with metal trusses, but I abandoned that idea because of the stud strength. Email me if you want more info!
Hi, fun video thanks. Were you able to achieve the minimum edge distances of 7xbolt diameter and 4x bolt diameter (UK) in the connection between the chords and the primary rafters. This is often what stops this type of truss being a viable option? Often there's not enough depth in the original truss primarys.
Hi Ryan - great comment. I doubt we achieved the UK standard of 7xbolt diameter between the center of the rafter and the edge of the existing rafter because the existing rafter was 3.5 inches and bolt dia was 0.375". 3.5/2 = 1.75. 1.75/.375 = 4.67. 4.67
I would like to do something similar to what you did although my current garage ceiling has drywall on it. It, too, has trusses. It's the 4th stall on my 4-car garage and has no bedroom above unlike the other 3 garage stalls. I'm a PE myself but in Electrical Engineering so my training and license wouldn't be much help. lol. However, my classes in Vector Statics should at least help me understand what's at hand. I suppose you didn't have to get permits or approvals for this since you would've been the person someone would approach to get the design approved and stamped anyway. So you can say "Yeah, a PE approved my design". lol. So, my question is: Why did you feel the need to use grade 8 bolts instead of just nails? I guess bolts would be better. I live in California and it doesn't snow here. My roof pitch is maybe 4/12 (I need to measure it). Thanks again for your informational video.
Thanks for the question! I wish I had your garage, I would never leave! You are exactly right with the permit and me being a ME PE. Every state is different. Also, every ceiling occasionally needs... *ahem*... repairs. I used grade 8 bolts because they more accurately translate forces through trusses as pinned connections do in Statics. Screws tear the wood up and are not very strong by themselves, and often are weakened during installation. You can look up the shear strength of any bolt, any grade - with screws this is sometimes a challenge and ambiguous. Grade 8 is relatively strong automotive grade, without breaking the bank. We connected the "king post" using Simpson galvanized tie plates with 10d nails. But, the king post is generally in compression anyways. Any other questions, feel free to reach out Augie!
How did you determine how far down from the roof peak to attach the trusses to prevent walls from pushing out? All the way to the bottom is ideal for push-out prevention (but no headroom) and all the way to the top is max headroom but no wall push-out prevention. Somewhere in between is a sweet spot for a middle ground. Would you start with the required headroom and lower the trusses as low as you can and still have that required headroom? I suppose that would work, right?
For bolt shear strength requirements, do you calculate the tension on the new scissor truss members and use that as a requirement for the bolts (plus safety factor)? What number can I use for roof weight calcs? I have a concrete tile roof. Do I find the typical lbf/ft^2 of my roof material and use that? That sounds like it would work. Thanks again for all your insight.
I'm going to raise my garage ceiling for my 4 post lift. I need to lift the ceiling 18 inches . I have to modify 3 frink trusses that are a 4/12 pitch in a 24x24 garage in Michigan. one way I thought is do what u did. the other was to use 2x8 rafters 24oc and pound one truss all the way to the left and two trusses to the right with a ridge beam tied to the doubled and the tripled trusses I pound over .sounds like a big headache . or getting Tuess gusset plates and converting the existing trusses to a scissor truss so it looks like they were made that way . any ides ? or advise? Thanks for the video.
I think either way you proposed would work. The pounding method sounds like a pain because you will probably hit a lot of nails coming through the shingles and imperfections in the OSB roof boards. Gusset plates are the strongest way to make trusses - I would go with the scissor modification + gusset them too; 12 inches on center if possible
I believe in a ridge beam roof either end of the ridge beam needs vertical/column reinforcement. I considered doing this along the entire length of the garage but wasn't comfortable with the load calculation
How much did this weaken the structure on the outside walls? since you removed the horizontal stringers the weight would put horizontal force outwards on the outside walls that the trusses sit on , right? or did the way you build these somehow limit the amount of that force?
Good question! On a traditional truss, the horizontal lower chord directly prevents the walls from moving outward, as you state. I run calcs on the original truss, and find out what the safety factor is under maximum load conditions. In my case this was 9! The new scissors trusses still have to deal with the same horizontal force you mention, and they are WORSE at it because of the angled lower chords as opposed to the single straight lower chord (the horizontal forces now have leverage over the truss members). That is why I had to double up on the number of new trusses and make the trusses out of 2x6's instead of 2x4's. I think the new trusses by themselves were about 50% as strong as the original truss. By doubling the number, I achieved the same safety factor. Long explanation, but this is why you need some sort of "truss" and you can't just cut all the members out; your roof would just flatten and your walls would push out. Last note: additional horizontal "collar ties" make any truss stronger. It was just overkill in my case, so I did not add these!
@@EnigmaEngineering Good explanation, Thanks. I'm curious if you could have also built these trusses like they do when vaulting a ceiling or a beam and pillar roof like what is used for cathedral ceilings.
@@sergeantseven4240 I am not a roofing specialist. But, I considered a few other options from an engineering standpoint. For example, steel parallel chord trusses can be much narrower between chords than wood and offer more vertical space. A cathedral style ceiling (with big lumber) is similar where there is a lot more strength in the members themselves compared to 2x4s. But, when I ran some calcs on the steel trusses, the weight was very high and I was nearing the strength of the existing ridge plates/studs which was concerning. Also, cost. I think other types of roofs like cathedral, hip roofs, etc., incorporate some sort of reinforced "perimeter" top plate that helps them withstand the horizontal forces; I wanted to avoid this just because of the added complexity
@@EnigmaEngineering Any problems passing inspection or getting permits for this? I always want to do these kinds of projects but the red tape is always too intimidating.
Couldn't you have sandwiched the trusses together in pairs of 2’s or 3’s instead of having them evenly spaced? Also, isn't the grade-8 hardware way stronger than the wood? Seems the wood will tear out/break long before a grade 8 will sheer. Seems like grade 8 would be an unnecessary added cost over, say grade 5. I have spent my entire adult life building homes and I've never seen grade-8 hardware used through lumber. Lastly, 4-1/4” thick concrete seems thin for a lift.
How far apart are your trusses? I have a 22'x10' patio that I want to put a roof over (no walls just posts and a roof). I am thinking 4/12 slope with scissor trusses to be able to have fans and lights. Also i live in Hawaii and don't really have to worry about snow buildup on the roof haha.
Hi Austin! Our original trusses were 24" center on center. I would imagine for your patio you could get by with even larger spacing than that. Our modified trusses were 12" CoC. You just don't want to turn your roof into a parachute in a wind storm, so I would recommend using good hardware and solid connections (hurricane ties, nail plates, 10d nails, corrosion resistant steel bolts with lock nuts/washers where possible)
11:22 I see vertical pieces (about 18" long) in the upper middle portion of the screen that is sandwiched between the 2 new 2x6's. How is that fastened to to the top since that lines up with the existing truss members?
Like many other commenters, I would like to do the same thing for the same reason. What is the slope of your roof and the depth of the garage? Did you use 2X6s or 2X8s? Also, it looked like you sistered a 2X4 to the rafter. Why?
Hi Joe! Roof is 5/12 pitch, depth of garage is approximately 23.5 feet. We used 2x6s. We only sistered the 2x4s from the original rafters (I think that is your question). We modified all of the original trusses and added 2x6s in to make them scissors trusses. For the new additional trusses, we went with all 2x6 - make sense?
Those original 2x4 trusses are scary, my dad has those in my shed and I've measured them before and after heavy snowfalls and the deflection doesn't inspire much confidence. I was worried about hanging a kayak from them near the wall. I lift my jetski from my 2x6s ffs.
They are sketchy. Some of the nail plates are barely imbedded into the 2x4s from ones I have seen. But, the safety factor is usually really high for good reasons!
I need to modify two standard trusses in my poll barn. I built a mezzanine and the clearance under two trusses are a problem. Can I hire you to do the same engineering engine for me? I’ll put together Auto CAD mock-up of the trusses design and layout of the structure. If you’re interested let me know exactly what you’d need and the cost? TNX in Advance
Thankx been looking for a video like this for about a year now. So would you recommend hiring a structural engineer for this type of project, or can i follow this design? Very similar specs in my building as what you have here.
@@stevendickerson8453 Hey, sorry on the delayed response! What part of the country do you live in? We are up North so we get a ton of snow. 62 lbf/ft^2 is the max load seen on the roof here - therefore, we matched the safety factor, achieving the same strength. That is why we needed the additional set of trusses and made them out of the beefier 2x6s. I think if you did something similar you would be fine. Deadman idea is interesting; I would need to run calcs on that though. The problem, in general, with altering traditional trusses is that the walls push out easier - columns in the middle of the room might not prevent that
How do you know somebody is an engineer? It’s one of the first things they say.
Well, you can TALK to a nearby engineer and see if they will review this video and give you their ESSPURT opinion..
Or look at what all is being shown, build one of the trusses yourself, and test the theory with weights. Just don't stand directly under it when adding weight.
When someone says "I am an Engineer," it is just like someone announcing that "I am a Lawyer." An engineer has to complete a formal course of study in a recognized engineering discipline. The BIG three disciplines are Mechanical, Electrical, and Civil. Nearly every other discipline falls under the umbrella of study of those three categories. Once the degree has been bestowed upon the individual, they then have to look up their state's professional examination requirements to become an engineer. Some states are easier than others, meaning that if you hold a degree and pay the fee, you are an engineer. However, nearly every state has some exam requirement as well as a period of training under a Professional Engineer (PE). Once those requirements are met and fees have been paid, that individual may call themselves an "Engineer."
I did exactly this and increase my height from 2400mm to 3200mm for an almost cathedral style ceiling!!
Nice work on calculations I did the old school engineering where I slapped it and said “that’s not going anywhere”
house builder here, fantastic job and you taught an old dog a few tricks! thanks and keep up the good work!!
Fellow engineer here, I can't tell you how excited I am about finding this, as well as all the details and info you show. Great job! I have the same ceiling height and trusses in my 30'x72' pole barn and am wanting to do this! I have a 4 post lift coming and would love an extra 3 feet of lifting height!
Hi jamie, how did your project go ? I have the same size garage but will turn it into living space trying to maje the same type of structure they did
@@chinocool7481 I wrote this a year ago!?!! Man, I ummm, yeah need to get on this. I haven’t done it yet. Haha.
My brother (super nerd, chemical engineer) modeled my roof and current trusses in cad. Then we sent it and our new design to our retired mechanical engineer friend that loves doing structural analysis. He gave us mountains of data. Spreadsheets. Drawing sketches.
I put the project on hold to put flooring in my house, paint, and new trim. Gotta keep the wife happy. Then I’ve been insulating and wiring additional outlets in my pole barn.
Hopefully in spring or early summer I’ll get to it.
Hi, can you share some information from the mechanical engineer roof report? I'd comment on this video, but the guy owning the channel doesn't respond it seems like. I have feedback about the process. I'm a building inspector and woodworker. Install collar ties, a horizontal board through the truss. And put in strong back truss bracing. Basically a continuous board perpendicular to the trusses to prevent deflection sideways. Last, a double bottom cord is a good idea. This video did a great job, but hopefully some people see my three recommendations to make it much better. I'd probably install a ledger or double ledger at the side wall too.
FYI for those of you who might have more clearance for a lift but want to keep your standard garage door; you can special order angled horizontal garage door tracks to accommodate for more space for a lift. I did that a few times when I had a small garage door business for customers. Much cheaper than a new roll up door.
I've been trying to find info on doing pretty much the same thing, but I haven't come up with much. Any idea where I can find those angled tracks?
@@samerickson89 try to find a garage door supplier in your area, or talk to some smaller garage door repair places that might want to entertain the hunt. The rails were special order from the supplier to the manufacturer. It's not as crazy as it sounds. Mention high lift tracks
You’ll need different drums, longer cables, different spring(s) and side mount opener. Tell your local garage door company you want a high lift track set up for your door.
You are amazing. This is exactly the video I’ve been looking for. Much love, brother!
Thank you very much for the comment Jacob! I have been thinking about doing a video on this series and going more in depth with the calculations involved
@@EnigmaEngineering didn’t think you could top this, but here you come again :)
I’m trying to use this method to vault the ceilings in my PNW rancher. I messaged you on IG, any help is greatly appreciated 🙏🏽
Trying to do this to my ceiling. 25’ span with an engineered flat ceiling and collar ties.
I'm a professional mechanic who runs an auto repair business out of my home. I desperately need a lift in my garage but have 8ft ceilings. Id love an extra foot or two. My attick sits above the garage so this may be a challenge. Your comment about moving the garage opener to the side was a good nugget. Either way it's good to see there's somebody out there in my same predicament. Wish I had the engineering skills you do.
Thanks for the comment Josh! This is going to sound crazy, but one method I heard from a few people is to run wood beams through the existing trusses, then rent a crane, connect it to the beams, and pick the roof off the garage (after cutting around the perimeter to free everything up). Then you would add an extra 2 ft+ of framing/siding and put the roof back on. It would save you from having to re-roof, modify trusses, etc.
@@EnigmaEngineering that's one knarly nugget! But a doable one with a little motivation. Thanks brother!
This gives me hope for my garage. Can't wait to get an actual lift and sell my quickjack.
Wish I would have been more dedicated in mechanical engineering class now
Edit: honestly if you could make a video where you guide through the calculations so I could do this to mine safely that'd be awesome. I'm an electrical engineer so I could definitely follow along. Thanks for considering ✌️
Great idea using it. Also instead of the rolled if you want more R value, you can modify the track to run the angle of your new roof line, harder angle up instead of out. Neighbor just did in pole barn.
I've been thinking about doing this to my house roof for a couple years. I've talked with several contractors and they tell the same thing. Have to use a LVL or steel beam. I'm not buying it. I like what you did. Thanks for sharing your knowledge.
Hey Ray! No problem. Obviously I can't tell you exactly what to do with your build. But, the safety factor of trusses you can buy at a hardware store is generally pretty high (like ~7-10). My recommendation is finding a truss style that gives you the extra vertical room, then perhaps increasing the number of trusses like we did. For example, a scissors truss is weaker than a traditional truss. So, we doubled the # of trusses to approximately match the safety factor.
Nasa is definitely interested in your calculations ! Great job 👍
I have a similar truss situation. My plan is to cut all the sheeting and end fasting nails of the trusses that I'll be moving using a sawzall and once clear of all nails I'll slide the middle trusses away from center and against the outer trusses nailing them together to create a form of girder truss on each side of the bay. At that point I will span the 12' gap with structural 2X6s on 16" centers between the two "girder" trusses using joist hangers on each end of the 2X6 purlins to support the roof sheeting. This method opens the bay giving the maximum height possible while retaining the integrity of the structure.
Hi Delbert, I considered a similar method. It should work out fine! Thank you for the comment and thanks for subscribing
i put a mid rise lift in my single car garage last week, it hit one ceiling joist, so i converted that one joist into scissor joist using mostly aLL the wood already in place, no need to over engineer things.
IT took me just over 2 HRS.
up in north maine we get high snow loads but i installed a metal roof 4 yrs ago which gets rid of snow.
I'm here because an associate of mine removed his garage rafters and it left him with a HUGE amount of overhead space. I asked him "Don't you need those to maintain the structural integritiy of the garage? He just said "naw my garage is fine. Strong as ever. ". I have been chewing on doing mine every since. But the kicker is I DYI'ed an 18' addition to turn my 2 car into a 4 car years ago and I added the rafters because I thought they held the walls against the outwardly pressure of the A-frame pushing down . I didn't need gables .
Impressive!
I have the same roof layout in my garage, I’d love to do this at some point, I just really want a 2 post lift in there lol.
This is a great design. Amazing work
Thank you Chris!
My garage is my woodshop, and the ceilings are exactly 8' tall, which is often a problem when you factor in shop lights dangling 8-10" below that. I'm considering this as a future project... I am a Landscape Architect, but I work in a civil engineering firm with structural guys so between this video and them, I'm confident I could pull it off. Thanks brother.
Superb video. Looking to do something similar in my garage. I was told I would need a new roof. Nice to see it can be done another way.
Thanks James! Good luck with your garage
Awesome project! How is it holding up?
Great vid and thanks for sharing. This is exactly the project I've been pulling my hair out on having completed. Other than the engineering side of this project, I am capable of completing the work. My problem is several structural engineers won't advise or won't design for me. I just need the blueprint and specs. I can take it from there. You ever think of setting me up with a safe design based on my setup. I do have the original blueprints from the house built in '89.
Hey, thanks for the comment! More videos on the garage build to come. Regarding the design, I wouldn't advising you on your setup. I want everyone to have a super garage. The easiest way is probably finding me on instagram and PM'ing me: enigmaengineering
I need modify my roof high, I'll follow your method, I wait to find the kind screw that you used in my country but maybe I can to use someone similar in weight resistance or reforcer joins with iron plates, thanks for you time and excellent job.
Great Job, I'm about to do the same thing, that is how i found the video. This is very overbuilt, which is good. It seems you used Doug Fir instead of yellow pine. Doug Fir isn't supposed to be used in a joist / rafter type situation. Usually for studs only. Doug fir is much easier to work with though and in the end won't make a difference given how overbuilt this is. You could have also scabbed osb to the side of the Scissor truss after adding another 2x6 to even the thickness instead of adding another truss inbetween. If you do this method the OSB should be nailed or stapled every 6"s or so
What is the spand of your trusses? and what size timber did you use?
Also what snow payload did you calculate for? 1kn/m2? and are your trusses spaced 3 feet apart?
What is the roof pitch and what are your ceiling pitch? They should be 10-15 degrees different depending on the slope of the roof.
Great work. Planning to do this for a bedroom
Awesome!
Nice!
Great video. Thank you so much for sharing. My garage is 28x40. Would I still do 3' 10" down from the top when insatalling the 2x6 sissors?
This is the video I’ve been looking for , wanting to do the same thing !
Excellent. Glad we could help!
I'm doing a single bay in my garage where my 2 post lift is but installing a ridge beam that'll be supported by the post of the car lift. Just gonna cut out all that mess.
What is the size of your garage? I plan to do this for one stall in my 30x40 barn. Put calculations together. Trying to compare to yours.
Awesome work man! I need to vault my garage ceiling as well as I want to be able to fit my 72 Cuda and 07 Mustang in 1 bay.
Thanks Jason! Now I have the garage - time to find the Cuda :)
@@EnigmaEngineering Goodluck! It took me 5+ years to find mine and I got lucky! I saw a rusted out frame of a 70 cuda missing hood, every door panel dinged, floor pans rusted out, no engine, transmission, wiring and the "car" sold for 20k...people are out of their minds when it comes to ebody cudas.
How is it holding up?
Thats why Engineers aren't allowed on the jobsite.... standing on the top of the ladder. :) Very cool, and wish more Engineers had to be occasionally TDA'd to their respective jobsites to see how the things they engineer actually are built, and how crazy some of their ideas are. I'm looking at you Nissan engineers, 2 hour job to replace spark pliugs.
Honda was no different, wanna change a starter or Ac compressor in a civic? Pull the engine. :-/ Next to the lawyers, the enginerds would be the next bus off the cliff.
How do you like new garage door and opener?
Wondering what that looks like, and if you plan on changing other larger garage door to match exterior look and style of new garage door?
Peace
Certainly seems like the shear strength of those bolts is doing a good portion of the heavy lifting here.
Any chance I can fly you out to do this on a similar garage? My local GCs also want to lift the roof 🙄
How did you add the scissor truss in between each existing truss? Did you add additional rafters to attach the truss to at the roof?
I have those trusses in 2x6 in my barn. I want to install a ceiling hoist across the trusses. First I installed grade 8 bolts on the center triangle and am installing cross 2x6 blocking starting from the front header. My lift weight on the hoist will be about 500 pounds, normally much less, on a 20 foot track bolted to the trusses with grade 8 bolts. Are the trusses able to handle the lifting weight?
Great video- thinking about the same for my 24 x 24 garage in NC but to get the necessary extra room for a golf simulator. You did't mention the span of the garage. And did you consider using engineered wood for added strength and rigidity? I am not an engineer but get the impression LSL or LVL timbers would have allowed not doubling the trusses. In any case very nice job!
Hi David, thanks for the comment! You are not alone on the golf simulator. The span was 23 feet in this example. We didn't consider engineered wood simply due to cost. But microllam or parallam would be great for this job. You likely would not have to double up the trusses either. I probably did not have to - I just wanted to match the original safety factor identically and I had never seen anyone else do this so was being extra cautious. Also - add in some collar ties for extra beef
An LVL would cost 10x what a 2x6 would.
I just need to get 6 inches in my double garage 5 trusses to modify so I can swing get a driver for my golf simulator. Is there a simple way of do this I am a carpenter here in Toronto and I loved your videos.
John
How far apart did you end up being on center with your trusses? I have a pole barn with a metal roof, trusses are on 2’ centers. Thanks.
I'm actually in the middle of starting this to my garage right now. Can you tell me what fasteners, or ties you used at the top plates at the end of the truss on top of the existing wall? Maybe I missed it.
Where can i get plans for this ?
Soo.. How would you go about reinforcing if you just wanted to cut 60" out of a single truss bottom cord? Trying to put in an attic lift..
I’m wanting to do this in my barn at home but it’s 30’ wide how do I figure up how long of boards I need? And how far down do you bolt the boards from the peak was that 3.5’ ft?
Hi Nick - you would want someone on a ladder to help you pull a tape measure for the exact dimension. We went down 2'-5" from the inside peak - but the more you get here (i.e., larger distance), the stronger the scissors will be.
This could be a game changer! Appreciate the video! How do you calculate how far down your 2x6 needs to be placed from the peak of the truss?
With no cross ties what’s to prevent the walls from bowing out? Guess I’m thinking where they have a cross tie 1/3 of the way up.
But is it to code? Did you get a permit? If you sell the house... will it be an issue?
I know if I walked into the garage and saw that.... I would question if it was to code.
Not a lot of codes exist for non-dwelling structures like sheds and garages in my home state. Never selling the house. But, definitely would be a slight concern otherwise. Generally our basement foundations are collapsing which is a bigger issue
You sound like a scared little man. He created a professional looking modification, this isn't some yahoo with a few scrap 2x, elmer's glue and a nail gun.
Looks great! Thinking about doing this in my garage for a lift. I live in Michigan. Any suggestions for me?
Thanks! We are just across the lake from you (unless you are UP). Google search "snow loads by state" and see where you are on the chart. We used 60 lbs/ft^2 to be safe and were well under the safety factor (i.e., less than 10% of the roof strength at full snow and wind load)
My suggestion is dont talk to this clown.
High there I am from bc Canada. I have a hoist in my garage currently with an 11 foot ceiling. The peak runs the same as your garage project. I already have a side mount opener and the tracks rammed basically right to the roof. I have plenty of room in the attic above the garage to do the same idea.
Do you have to or should you pre-load the new truss?
My current trusses are 2x6 should I go 2x8 or stay with 2x6 to do the same thing?
I would always upside for more strength - the strongest truss is a solid truss (it just weighs too much)
What size is this garage ? 10ft walls ? How wide and long is the garage ? Thanks
How are those modified trusses holding up thus far?
Hi Yassir. They have been 100% solid. At one point last season there was ~2 feet of snow/ice on the roof; the drywall has no visible cracks - no evidence of any movement
@@EnigmaEngineering Do you have a link with the drawings available? I have identical trusses.
Will this shop stay un insulated?
I need to do this also... my peak is 90 deg. from yours... how do I figure out the angle needed for the new tuss? my building is 28x32 the peak is on the long 32 front to back.
Hi Daver. Measure the distance to the peak of your garage. Then use something like google sketchup (free) to draw out the truss. Or send an email and we can help out: enigmaengineeringllc@gmail.com
@@EnigmaEngineering thanks
Thanks for doing this. Do you have any sense of whether there’s a version of this that can be done in Florida, where our houses have to meet code for hurricanes? (I think they need to withstand something like 150 mph winds.)
Thanks for the comment! I think a similar strategy should work in FL. I am from the Midwest and I think used 60 lbf/ft^2 for my combined "dead" and "live" loads accommodating 2 feet of snow + winds . Just a quick search showed 15 lbf/ft^2 dead load in Florida and at least a 30 lbf/ft^2 live load, so minimum 45 lbf/ft^2. But, an equation for wind force is P = .00256 * (Velocity)^2. At 120 MPH, P = 37 lbf/ft^2, so 37+15 = 52 lbf/ft^2 total load. But, to be safe, 150 MPH sustained wind speed would be P = 58 lbf/ft^2, so 73 lbf/ft^2 total load - this would be a very strong roof. Let me know if you want more thoughts!
This video is amazing. Can you kindly tell me all the steps one by one in written which you told on videos, so I can even write an article on it? Thank you!
Dude! Great video. I so wish you were a little farther south so you could be my Structural engineer in west chicago suburbs. I have the same issue but unfortunately have bobtail trusses on a hip roof garage. I am pretty sure that I could do it but I do not have the degree or certification to convince the municipality.
Well done. How'd you get those king posts to fit between the existing mending plates at the ridge? How'd you make those connections?
Thanks! Good question. The mending plate bottom edge on our original trusses did not come down below the the wood, so we had no issues with the king post. We did have to notch a few rafter ties with a grinding wheel and sawzall though. I suppose you might be able to do the same to a mending plate, then add new plates to the existing wood. We used structural screws with nail plates in a few places
Which cad program are you using?
Any idea what I should expect to pay a structural engineer to design something for me? Would this be something I could hire you for if I send you any and all dimensions? I took CAD in highschool and could easily send you something from SketchUp or something in isometric or front/side drawings
Hi Paul! It would not be that expensive - in the hundreds. I have helped a few people out with this (PE mechanical), send an email if you want: enigmaengineeringllc@gmail.com
So is this safe? Like can this kinda design be used for a house roof? Or just a garage roof
That is awesome! Looks very well done. We are looking at doing something similar to the gambrel roof on our barn/garage.
9:1 safety factor seems insanely high...you said you figured out the original safety factor, what was that?
I thi k he meant it was also 9 originally since he mentioned trying to match it
great idea and job!!! I need to do the same in my garage... my peak runs the other way 90 off your garage, so I would need to do the entire garage's trusses. did you do yours only because you needed one bay for working under the cars? what do you think the downside if any of doing the entire garage (other than cost and work LOL) Im doing a 4 post for 90% storage rather than work. I live in southern Cal so no snow load issues - just Spanish tile (fire protection) roof which heavy
thanks if you reply
How much would someone have to pay you to make those calculations for their own custom garage?
I want to remove the drywall from my garage ceiling. I plan on adding storage shelves to existing trusses so I can access easily all around the garage instead of crawling though my 4x4 opening.
What is the pros and cons to doing this?
did you ever consider adding the scissor trusses next to the original trusses and marring them to the original trusses? the only hurdle might be how the hold the truss ends. unless ledger boards might work to push up under the scissor truss after it has been married tot eh original truss. then cut out the un needed original truss.
My garage is very similar in construction and I've been looking for ideas to do the se thing for my lift. Funnily enough my S5 is one of the vehicle going on the lift so I laughed when there was an S5 at the start of the video.
What was the roof pitch of the existing garage?
Thank you for sharing your work. I am in the process of rebuilding/re-designing my garage and I would love to use that design.
Let me ask you about the size of the world you are using. Is this 2 x 8? Or just 2 x 6?
Hey, no problem! We were using 2x6s here, but the taller 2x8s would be stronger if you can make that work. Good luck!
Thanks, I'm gonna follow your advice and use 2 x 8.
@@Studio-yc3ko no problem. Also, you can add "collar ties" too for additional strength
@@EnigmaEngineering yes, absolutely. The concrete is poured, slowly I'm gearing up to start framing. I will keep you posted if you don't mind. :)
@@Studio-yc3ko absolutely. Good luck. Here is my email: enigmaengineeringllc.com
Why can't truss manufacturers supply the right kind of truss to sister to your truss with the gussets not completed so you have 2 halves that could easily be lifted in place then rent a press to complete the 3 or so joint plates. Seems like a reasonable DIY solution to modify in place. Fasten old truss to new everywhere practical. Then cut the stringers of the old truss to the bottom level of the new truss.
This solution in the video is great too but an inspector is unlikely to pass it if they can even get to it to see it.
Curious if you can do an update on the condition, any cracks in the drywall should be a good indicator of movement.
How would you vault a pyramid garage roof?
This will sound slightly crazy, but probably the easiest way for that style of roof is to lift the roof up with some jacks and then add a new section of studs around the perimeter of the gap at the top plate - I would have done that here but then my garage would have been outside of local building height codes
@@EnigmaEngineering Thank You!
Any chance could give a little advice off a picture? Morton building wanting to remove lower chord so can walk on the top of the built office spaces. So thinking of adding posts to truss to office walls on both sides of space then remove center lower chords. Basically extend the wall to upper roof chord and tie in the rest of the y sections back into 2x8 supports on 3 trusses. Making walking space into the attic space. If up to a little advice or opinion reply and I’ll give email.
Thanks
I wonder about the paperwork needed for this. Did you have to involve your county and your insurance company?
Question for you...what kind of pitch did you have on the current roof? My roof is a 12/12 pitch with 8' walls. That being said, i could possibly even get a little more ceiling height over boxed in areas? Plan on storing a car on and under left.
Am going to do this to garage just completing. I've already had my framing inspections and am awaiting my electrical then I can do my magic. Plan on reaching out if that's ok.
Thanks for the video, Les.
Hey Les. Thank you for the question! My roof pitch is 8/12. The biggest advantage of 12/12 is the availability of a horizontal collar tie below the king post that would greatly increase the strength of a modified truss in your case, while still give you plenty of overhead space. I would have to see a sketch of your roof and where you are meaning to store cars to answer your question. My email is in the contact info on our website, feel free to reach out! enigmaengineeringllc.com/
Are those trusses 8 in on Center? Holy mackerel. You could drive a tank over that roof. I just took my top of my trusses and I screwed plywood to them and it made my roof so stiff you could break your ankles walking around up there. Your roof is probably stronger than mine
So, you added what, (20), 20' 2"x6"s, (10) 18" verticle struts, (60)+ nut and bolt assemblies for a total of roughly 400-500#s? Did you add any upright supports to the top plate studs?
That sounds close to the weight we added to the roof. I calculated the strength in the 2x4 studs to check the general magnitude. But, I kept in mind that a fully-loaded 62 lbf/ft^2 roof would be over 50,000 lbs, so the 400-500 lbs didn't concern me too much. The additional weight over the garage door header was a larger concern (ended up fine on this). There is a lot here - at one point I thought about going with metal trusses, but I abandoned that idea because of the stud strength. Email me if you want more info!
Definitely interested in doing this in my garage. The link for your service page does not work; are you still offering this service?
Hi, fun video thanks. Were you able to achieve the minimum edge distances of 7xbolt diameter and 4x bolt diameter (UK) in the connection between the chords and the primary rafters. This is often what stops this type of truss being a viable option? Often there's not enough depth in the original truss primarys.
Hi Ryan - great comment. I doubt we achieved the UK standard of 7xbolt diameter between the center of the rafter and the edge of the existing rafter because the existing rafter was 3.5 inches and bolt dia was 0.375". 3.5/2 = 1.75. 1.75/.375 = 4.67. 4.67
I would like to do something similar to what you did although my current garage ceiling has drywall on it. It, too, has trusses. It's the 4th stall on my 4-car garage and has no bedroom above unlike the other 3 garage stalls. I'm a PE myself but in Electrical Engineering so my training and license wouldn't be much help. lol. However, my classes in Vector Statics should at least help me understand what's at hand. I suppose you didn't have to get permits or approvals for this since you would've been the person someone would approach to get the design approved and stamped anyway. So you can say "Yeah, a PE approved my design". lol.
So, my question is: Why did you feel the need to use grade 8 bolts instead of just nails? I guess bolts would be better. I live in California and it doesn't snow here. My roof pitch is maybe 4/12 (I need to measure it).
Thanks again for your informational video.
Thanks for the question! I wish I had your garage, I would never leave! You are exactly right with the permit and me being a ME PE. Every state is different. Also, every ceiling occasionally needs... *ahem*... repairs. I used grade 8 bolts because they more accurately translate forces through trusses as pinned connections do in Statics. Screws tear the wood up and are not very strong by themselves, and often are weakened during installation. You can look up the shear strength of any bolt, any grade - with screws this is sometimes a challenge and ambiguous. Grade 8 is relatively strong automotive grade, without breaking the bank. We connected the "king post" using Simpson galvanized tie plates with 10d nails. But, the king post is generally in compression anyways. Any other questions, feel free to reach out Augie!
How did you determine how far down from the roof peak to attach the trusses to prevent walls from pushing out? All the way to the bottom is ideal for push-out prevention (but no headroom) and all the way to the top is max headroom but no wall push-out prevention. Somewhere in between is a sweet spot for a middle ground. Would you start with the required headroom and lower the trusses as low as you can and still have that required headroom? I suppose that would work, right?
For bolt shear strength requirements, do you calculate the tension on the new scissor truss members and use that as a requirement for the bolts (plus safety factor)? What number can I use for roof weight calcs? I have a concrete tile roof. Do I find the typical lbf/ft^2 of my roof material and use that? That sounds like it would work. Thanks again for all your insight.
I'm going to raise my garage ceiling for my 4 post lift. I need to lift the ceiling 18 inches . I have to modify 3 frink trusses that are a 4/12 pitch in a 24x24 garage in Michigan. one way I thought is do what u did. the other was to use 2x8 rafters 24oc and pound one truss all the way to the left and two trusses to the right with a ridge beam tied to the doubled and the tripled trusses I pound over .sounds like a big headache . or getting Tuess gusset plates and converting the existing trusses to a scissor truss so it looks like they were made that way . any ides ? or advise? Thanks for the video.
I think either way you proposed would work. The pounding method sounds like a pain because you will probably hit a lot of nails coming through the shingles and imperfections in the OSB roof boards. Gusset plates are the strongest way to make trusses - I would go with the scissor modification + gusset them too; 12 inches on center if possible
Why couldn’t you just sister the existing 2x4 truss with a double 2x6 with a ridge beam and use a collar tie at the top ? Just like a cut roof .
I believe in a ridge beam roof either end of the ridge beam needs vertical/column reinforcement. I considered doing this along the entire length of the garage but wasn't comfortable with the load calculation
How much did this weaken the structure on the outside walls? since you removed the horizontal stringers the weight would put horizontal force outwards on the outside walls that the trusses sit on , right? or did the way you build these somehow limit the amount of that force?
Good question! On a traditional truss, the horizontal lower chord directly prevents the walls from moving outward, as you state. I run calcs on the original truss, and find out what the safety factor is under maximum load conditions. In my case this was 9! The new scissors trusses still have to deal with the same horizontal force you mention, and they are WORSE at it because of the angled lower chords as opposed to the single straight lower chord (the horizontal forces now have leverage over the truss members). That is why I had to double up on the number of new trusses and make the trusses out of 2x6's instead of 2x4's. I think the new trusses by themselves were about 50% as strong as the original truss. By doubling the number, I achieved the same safety factor. Long explanation, but this is why you need some sort of "truss" and you can't just cut all the members out; your roof would just flatten and your walls would push out. Last note: additional horizontal "collar ties" make any truss stronger. It was just overkill in my case, so I did not add these!
@@EnigmaEngineering Good explanation, Thanks. I'm curious if you could have also built these trusses like they do when vaulting a ceiling or a beam and pillar roof like what is used for cathedral ceilings.
@@sergeantseven4240 I am not a roofing specialist. But, I considered a few other options from an engineering standpoint. For example, steel parallel chord trusses can be much narrower between chords than wood and offer more vertical space. A cathedral style ceiling (with big lumber) is similar where there is a lot more strength in the members themselves compared to 2x4s. But, when I ran some calcs on the steel trusses, the weight was very high and I was nearing the strength of the existing ridge plates/studs which was concerning. Also, cost. I think other types of roofs like cathedral, hip roofs, etc., incorporate some sort of reinforced "perimeter" top plate that helps them withstand the horizontal forces; I wanted to avoid this just because of the added complexity
@@EnigmaEngineering Any problems passing inspection or getting permits for this? I always want to do these kinds of projects but the red tape is always too intimidating.
Well I guess you would be too scared to use the store-bought scissor trusses then.
Couldn't you have sandwiched the trusses together in pairs of 2’s or 3’s instead of having them evenly spaced? Also, isn't the grade-8 hardware way stronger than the wood? Seems the wood will tear out/break long before a grade 8 will sheer. Seems like grade 8 would be an unnecessary added cost over, say grade 5. I have spent my entire adult life building homes and I've never seen grade-8 hardware used through lumber. Lastly, 4-1/4” thick concrete seems thin for a lift.
How much does this cost??? Is it expensive to do?
What is the length and width of your shop mine is almost identical and wanting to do the same thanks!
29' 6" by 23' 6" Do it! It has been a great addition
How far apart are your trusses? I have a 22'x10' patio that I want to put a roof over (no walls just posts and a roof). I am thinking 4/12 slope with scissor trusses to be able to have fans and lights. Also i live in Hawaii and don't really have to worry about snow buildup on the roof haha.
Hi Austin! Our original trusses were 24" center on center. I would imagine for your patio you could get by with even larger spacing than that. Our modified trusses were 12" CoC. You just don't want to turn your roof into a parachute in a wind storm, so I would recommend using good hardware and solid connections (hurricane ties, nail plates, 10d nails, corrosion resistant steel bolts with lock nuts/washers where possible)
Enigma Engineering Sounds good! Thanks brother.
@@austinamaro No problem!
Grade 8 bolt in wood???
11:22 I see vertical pieces (about 18" long) in the upper middle portion of the screen that is sandwiched between the 2 new 2x6's. How is that fastened to to the top since that lines up with the existing truss members?
Its just centered...you could toe nail screw it to keep it centered
Like many other commenters, I would like to do the same thing for the same reason. What is the slope of your roof and the depth of the garage? Did you use 2X6s or 2X8s? Also, it looked like you sistered a 2X4 to the rafter. Why?
Hi Joe! Roof is 5/12 pitch, depth of garage is approximately 23.5 feet. We used 2x6s. We only sistered the 2x4s from the original rafters (I think that is your question). We modified all of the original trusses and added 2x6s in to make them scissors trusses. For the new additional trusses, we went with all 2x6 - make sense?
Those original 2x4 trusses are scary, my dad has those in my shed and I've measured them before and after heavy snowfalls and the deflection doesn't inspire much confidence. I was worried about hanging a kayak from them near the wall. I lift my jetski from my 2x6s ffs.
They are sketchy. Some of the nail plates are barely imbedded into the 2x4s from ones I have seen. But, the safety factor is usually really high for good reasons!
You're supposed to leave a little bit of space in between the boards and the bottom side of the roof because you don't want it rubbing.
I need to modify two standard trusses in my poll barn. I built a mezzanine and the clearance under two trusses are a problem. Can I hire you to do the same engineering engine for me? I’ll put together Auto CAD mock-up of the trusses design and layout of the structure. If you’re interested let me know exactly what you’d need and the cost? TNX in Advance
Thankx been looking for a video like this for about a year now. So would you recommend hiring a structural engineer for this type of project, or can i follow this design? Very similar specs in my building as what you have here.
Oh , i was also thinking about using the lift columns as extra support. As Like a deadman support to the concrete. Any suggestions is very welcome.
@@stevendickerson8453 Hey, sorry on the delayed response! What part of the country do you live in? We are up North so we get a ton of snow. 62 lbf/ft^2 is the max load seen on the roof here - therefore, we matched the safety factor, achieving the same strength. That is why we needed the additional set of trusses and made them out of the beefier 2x6s. I think if you did something similar you would be fine. Deadman idea is interesting; I would need to run calcs on that though. The problem, in general, with altering traditional trusses is that the walls push out easier - columns in the middle of the room might not prevent that
I’ve been wanting to take a center span wall out under my roof trusses for a while now I may look into doing something similar
Did the same calculations in a Truss app. I know the math but never have the time.
Do we need permission for this ? I want to do this for my car lift too