Off-Grid Mountainside BarnBuildEp. 2 | How-To: Dry Stack Block & Surface Bonding Cement Foundation
ฝัง
- เผยแพร่เมื่อ 19 มี.ค. 2022
- We are finally getting close to completing the foundation for our Barn Build. There are three retaining walls which we build with concrete block (CMUs if you want to be fancy but not cinder block) which was dry stacked and parged with a surface bonding cement. Each footer for the walls is fully rebar-ed and all the block voids will be filled with concrete.
Utilizing advanced framing techniques, building science and a limited budget, we set out to build an affordable living quarters/workspace above an animal barn. We want the building to reflect our existing home's modified Saltbox shape, but of course with our own design and eye for clean lines, functional features while utilize resources our Appalachia homestead provides us.
You'll find this in the beams and columns from Poplar and Black Locust felled at the building site, to locally sawn Hemlock for traditional board and batten siding site finished using the Japanese wood treatment Yakisuki (aka Shou Sugi Ban).
Poe Run Craft and Provisions is a nonprofit organization dedicated to community vitality through art, food, and nature. Located on 40 acres of mountainside in Elkins, West Virginia, run by Margaret Bruning and David Long.
We post new most every week, weather permitting!
Subscribe and hit the bell to get notified when our new content is available.
If you're interested in any of our seasonal, small-batch products, please consider visiting our online shop: www.poerun.org/shop
Website: www.poerun.org
Facebook: / poerun
Instagram: / poeruncraftprovisions
Airbnb: airbnb.com/h/back-to-the-land...
Affiliate Links (we earn a small commission which helps us continue to make more content)
Sawzall:amzn.to/3mxfpIO
Angle Grinder: amzn.to/3yji7Ze
Concrete Blade: amzn.to/3ynK3LG
#construction #barnbuild #poeruncraftandprovisions
Because there have been a number of comments regarding SBC, its longevity and strength, here is a post from NCMA.
ncma.org/resource/surface-bonded-concrete-masonry-construction/
If you read through, you'll find SBC is just as strong (or stronger) as mortar with the exception of compression unless you grind the mating surfaces. Working the math, unground CMU is about 30% strength which is about 750psi. I calculate the weight of the building *including* footers/block walls and 70 psl live load/80psi on roof @ 300,000 pounds. A 2000sf house is about 400K pounds, this building is 900sf, so I'm way over estimating the building weights. There's 495 square inches of bearing on the three walls from 11 columns and 30' short 2x6 framed wall which is ~610 psi, well under the 750psi as listed. BUT this does not account for filling ALL voids with concrete, in our build a 2,500 psi mix. Code requires, in many regions, filling the voids that have rebar.
I was in the home building business for over 45 years.
The business originated as a masonry business, as my father was a bricklayer by trade.
Of coarse much of the work was blockwork.
Actually a dry stacked wall done properly as this one is, with vertical rebar and a bond beam with rebar then the entire wall filled with concrete is much stronger than a conventionally layed wall using mortar joints.
The parging is simply to cover the joints and add a finish look.
However, the parge coat would also add an additional strength factor if fiber is added to the mortar while mixing.
Thank you for sharing your experience Ernie!
Omg.! There is no evidence to back anything up you said . If a mortared wall and a dry stack wall are both filled with concrete and rebar they will be nearly equal . Dry stack doesn’t add strength😅 . Some of these comments are hilarious
@@Nctbgs Suggestion: Reread what was written before you comment:
".....stacked wall [....] with vertical rebar and a bond beam with rebar then the entire wall filled with concrete is much stronger than a conventionally laid wall using mortar joints."
Conventionally laid, aka mortar joint, CMU walls typically only have the cavities filled that contain the vertical rebar ties that stick out of the footer (which is every 4ft by code). All other cavities are not filled unless specified,, and in the rare even they ARE filled, it's not with concrete, but perlite or vermiculite loose fill for insulation value (aka no strength added). So a filled dry-stack wall with the bond beam and vertical ties would be stronger. The info IS widely available from Quikrete, Sakrete, and Building Science Corp. to name a few.
Now, if a conventional wall has all cavities filled with concrete, it'll be stronger than the above filled dry stack, but again, most block walls are not solid filled.
@@l.a.martin2424 Well ONE would agree "IF" the wall was just laid up as a CMU block wall (with the joints mortared) and "NOT reinforced" and "NOT" Grout FILLED! (But his method probably is stronger than the scenario I am describing here?)
Great job.
I like using "Quickwall brand" its white, its a little pricey but its very durable/strong
I'd double up on the vertical rebar if the wall is retaining earth, but in general, this method is perfectly acceptable. Bonding the blocks together with mortar adds no additional strength.
I may need to consider using this method.
Guess where those blocks came from? That's right, the grid.
Hello! I think you may be confusing our off-grid building with the use of electricity. It will cost anywhere from $6,000 - $10,000 to connect this building to the existing power line on our property and add a new overhead pole and transformer right next to the building. It would also be considered a commercial connection, adding 15-20% to every kilowatt we use. In contrast, solar cost $7,000 and no monthly bills.
@@PoeRunCraftProvisions ah I see. You mean the electricity part. Thanks for clarifying.
I built an entire walk out basement with this method in 2000 but did not fill the blocks with grout and this basement never leaked cracked or showed any signs of being inadequate. This was in Maryland so entire method was approved by inspector after I showed him quikcrete's Quik wall technical info.
I just found your channel , wow , the way you coat the wall so great , it does looks to complete 👍
Cool stuff! How does this method compare to laying block with mortar joints?
Hi Lenny, It was incredibly easy and fast to stack the block and adjust it for plumb and straight even with 5 or 6 courses. We chose this method because I wasn't experienced enough with laying block/brick to confidently make straight, level courses. Parging the wall was easy too.. If I had to do it all over again, I'd still chose this method.
Your dog's name should be "Faithful"
❤❤❤❤❤
I like your dog.
How close did you space the vertical rebars in the CMU blocks for this wall? And out of curiosity WHY dd a DRY STACK and not mortar the CMU ?
Hello! Vertical rebar was placed about 32" apart. The slightly long answer to the second question... I'd used BBond, an industrial version of SBC used in mining, to fix a CMU wall at our main house. The block had failed due to excessive moisture and a lack of draining. Surface bonding cement does provide water resistance so didn't need to apply a water protection/drainage layer at the house or this build. Second I wasn't confident enough to lay level courses using mortar, though I would have gotten a lot better at it as I progressed. BUT I'd still have to apply some sort of drainage plane/water resistance layer to the buried side of each wall. And I think plain CMU walls are unattractive, so I'd also have to "stucco" the exposed sides. All that is accomplished with SBC in one process.
Please see the pinned post if you have questions about SBC strength and some simple structural math. I know a number of "old-school" comments say SBC will fail, but that is not what the mining industry says nor all the science.
So basically you just used the dry stack as a sort of form to hold the concrete filler? and surface cement as a water barrier?
Kind of.... To make/build/rent concrete forms for a solid concrete wall would have been a lot more expensive, and I'd still need some sort of water resistant barrier on the side being buried with dirt and gravel.
Why do you need to skim coat the block if you are filling the voids with grout?
Great question... Surface bonding cement (SBC) basically replaces the mortar, which holds all the block in place. If you skipped this step, the blocks would still be independent and could easily move when filling the voids. Second SBC provides a water resistant layer, protecting the block which is very very porous from water infiltration which would slowly crack and fail with our freeze/thawing in winter. And finally, which didn't matter to us, but if you build a wall you want to parge with stucco, this could SBC would replace the mortar and stucco process and be tinted too.
Hope that helps.
@@PoeRunCraftProvisions Thx for the feedback.
What about filing all the blocks with concrete?
Hope you continued watching the next episodes where we do fill all the block.
Can dry stacking be used on a typical below grade, full basement footing (footer 6-7’ below grade)? What about in norther US where we have a freeze/thaw cycle?
Hello. That is what we have done, but only 3'-4' deep which is well below our freeze line. Couple of other considerations, retaining walls over 4' should be checked by an engineer (I kept mine at 4' and under) and you must have good drainage with perforated pipe at the bottom.. Don't backfill with soil, only gravel to finished grade and use a good quality unwoven fabric NOT landscape fabric. Unwoven fabric will allow water in and be drained away.
As your video stands, I would caution viewers not to build a wall this way unless it is non-structural. I am assuming you vertically core-filled the block with rebar in them and the non-rebar cores are left hollow. That gives your wall almost no structural strength again side loads (Earth) except for a solid column every 4’-ish. Parging a wall adds nominal strength only. It is merely a waterproofing and cosmetic addition. The video said you parged 1/4” but it showed about 1/16” layer so you must have added 3 more coats? Even 1/4” Portland cement is “brittle.” Concrete/grout is strong because of the aggregate added to portland. The bigger the aggregate the stronger the mix. Portland is just the glue that holds the aggregate together. It adds little in actual strength. I don’t know what your walls are for and this video is incomplete so I pass no judgement on you. Simply a caution to viewers thinking they can skip grouting CMUs by adding a few core fills and parging the outside. If it was that easy then every mason would build walls this way. Check out Mason the mason or Mike Hadock (maybe Haddock) on structural wall building.
Hello! Please see pinned post with details and a link explaining the use of this product vs mortar joints.
I encourage you to watch the next videos in which we do fill every void. Also this isn't portland cement used to parge the wall, it's a surface bonding cement, which includes fibers and is specifically designed for this purpose. I also included some calculations in the post for more detail, though overturning and slip calculations were not included, I did that math too, please see the introduction video in this playlist. There is a lot of new science that was researched to get to this point in the build. That said, I agree don't just build a wall because I did, do the math and the research for your project. Thanks for watching!
I thought you’re supposed to put cement inside
Hi Gitanagurl, yes we did fill all the voids with concrete in episodes 3 & 4, about a 3000 mix and completed our 12 yards of concrete for the foundation. The SBC basically replaces the mortar and is a water barrier. Hope that answers your question!
Hmm I don’t get it. Seems dangerous….. anyone that goes to sit or lean on it and the wall topples over
Surface bonding cement is fiber-reinforced. When a block wall is parged with it, the layer of cement bonds it all together. As long as he is adding reinforcement steel in the cores and bond beams, this wall will be every bit as strong as a mortared wall.
Surface bonding is not enough , blocks need to be bonded too.
could you explain what you mean?
SBC does bond the blocks together, and according to all the documentation it's stronger than typical mortar. Also just like a traditional mortared wall, there is vertical and horizontal rebar and grout in all the voids
Not true, I've built two houses with this method and did not fill the blocks with grout on full basement walls and they were the strongest most water resistant walls I've ever built.
@@Alongfortheride693 Sorry house has a 2000 square foot basement buried on three sides with a walkout and the basement is absolutely dry, you do realize they use this method for hatcheries that hold water in surface bonded cinderblock water enclosures. by the way I lived in this house I built for myself so I should know.
I was skeptical at first. After tons of research, I found many articles saying it can be stronger than mortared joints. They must be filled and properly reinforced. One of the main reasons mortar was and is used was because of the issues with the blocks not being exactly the same. Another is the dangers of other trades coming in and moving the wall before grout day. The blocks are made much better now. I used to deliver to a block plant (old castle block). They showed me around once. I must say I have to believe the articles I read. There are times when mortar is a must. I’m a Mason as well. Not trying to say anything bad about mortaring joints. It’s just a great alternative when you have unskilled/less skilled labor. I’m going to build a privacy wall this way. I may post the video.
I've been in the masonry industry all my life, grew up in it. I've never seen anything so stupid as this!!!
This is just being lazy, incompetence, or ignorance of building norms and codes. Maybe all three.
Please consider reading the pinned post and the relevant link regarding surface bonding cement vs mortar. And remember, the whole wall is filled with rebar and concrete.
@@PoeRunCraftProvisions read it. I stand by my statement.
This is the worst idea ever.
Unless you fill those cells with concrete, and run rebar every 3rd cell, you have very little lateral strength ...After a few winters of heaving and settling it will begin to tweak on you.....the surface coating does very little for strength...those that have lucked out, Bravo.....But every one that stands there are triple that eventually fail...There's no real shortcut to a proper foundation
he did fill the cells in another video. Probably fine for the purpose, but yea walls experience a huge amount of pressure over time. Even the most expensive, overbuilt ones can fail due to ground conditions or events.