Fantastic..... I'm a bit further down the road with my, almost identical build. If ever the phrases, "the Devil is in the detail" and "planning is everything" come to the fore...... this is it...... So many peeps in the trade can't get their heads around this.....
Trade just haven't spent enough time figuring out what works well and what doesn't work well with warm roofs. They will get there, but it's early days. So good to see Robin sharing his ideas for how to do it well. The energy efficiency of the finished home is well worth the ttime spent getting the design right.
@@andrewpritchard5328 In the Military It was the 7P`s = "Perfect - Pre - Planning - Prevents - Piss -Poor -Performance." and if you failed at a task it was the 4 F`s = "Found it, Flaked it, Failed it, Fuck it." 👍🤔
Any thing to think about if mounting PV on a warm roof? Can you do a vid on the fixings that go through the external rafters? Calculating the spacings, the length, the angle they're inserted, figuring out the local wind factors...?
Really enjoy your videos, it's great from an architects point of view to see someone who is great at what they do and highlights where buildability issues crop up - super useful as it's hard to predict these issues on a drawing board.
I would class this as a Hybrid roof because you have introduced a ventilation on top of the insulation, a warm roof for me is when the finish product is fitted directly to the insulation.
@@davidscott3292 It can be done, with the primary battens nailed through the insulation. One must be mindful of the fixing detail as the 150mm insulation doesn't really 'support' the fixing so the weight of the tiles and wind uplift calcs must be considered.
Robin love the video, amazing craftsmanship detail detail detail love it, but how on earth do you even price a job this size, a video on how you price a job like this would be beneficial, amazing 👍💪
I'm a bit of a fanatic too. A building control officer said to me once, "come on we're not building a spaceship". We I think we are now..! Every insulation,and membrane manufacturers specification are different.... Easy to get headaches these days
Robin that's great work pir is a hard material to get precise so many don't but that must have been an impossible job to price measuring cutting fitting tapig and then battons hope whoever lives there appreciated the detail
Great to see quality work with well thought out detail. Keep posting these informative and knowledgeable vids. I’m sure younger people entering the trade benefit from your years of experience. Devil is in the details! Unfortunately customers are sometime persuaded that Price is the crucial element. Quality work, strong detailing lasts longer and is more efficient over time. 👏
Wonderful to see and thank you for sharing. My only gripe is that the dormers are being done as a cold roof, which is a shame given the insulation levels to the rest of the roof, but it certainly doesn't detract from the precision work you have here, it's great to see!
Outstanding! Congratulations on your success. In my opinion that is a world leading structure. In your follow up video could you go into the cross flow ventilation to the rafter. You mentioned an over fascia vent which i imagine is purely for the counter lath. Your soffit i imagine is going to be vented on the eaves and you have a detail in the ridge to complete the ventilation down to the rafter.
Another great video Robin. If only we could clone you a few thousand times we'd have a chance of the new builds lasting something like the length of time the Victorians expected and also only costing a few hundred pounds a year to heat. Every job I do I find myself asking, how would Robin do this ? Bravo Robin and keep up the great work.
Actually just did a bit of searching and you can get an eaves closure piece that fits under the GRP valley at eaves level, looks very neat but like most things it might be a bugger to fit in real life.
Kinda strange seal everything up ,warm roof then go and add cold air albeit above insulation ,cold side it’s all getting a mine field to understand but great work as always
A master piece of a structure. Well done Robin.I believe you should express all your lineal dimensions,in it's imperial equivalent for the benefit of USA subscribers.
Hi Robin. I hope you registered the IP for the attachment for the ISC240. Then you can sell the license to Festool. Should be pretty easy to manufacture out of plastic/metal plate, but I would leave them to figure that out and just get them to pay you a license for each one sold. Easy money. Might not be as much as manufactoring it yourself but the pennies add up to pounds.
I contacted building control to ask what my local regulations are (as I moved up the other end of the country) I was told work done would need to be to the Building Regulations 2010 as would be applicable anyway in the England.
Excellent insulation values, though missing a key component for the envelope, vapor diffusion. Typically in cooler climate zones vapor pressure drive is outward. The interior OSB is enough of a vapor restrictor to inhibit this outward drive. The foil faced exterior is a vapor barrier on the wrong side, inhibiting outward vapor diffusive drying. And does very little to control heat transfer. Cold climate research shows the exterior radiant barrier only reduces heat transfer by 2%, though blocks vapor on the cold side. More important to stop air flow with continuous membranes that are permeable and liquid water tight.
Lovely work again Robin. Lots of work to do from the looks of it, how many guys would you have working with you on the joinery on a job like this? Thanks
Thing of beauty. So nice to not see steel in the two roofs I’ve seen you do on TH-cam. I’ve tried to convince two contractors I work with to investigate your method and they’ve dismissed it as too expensive. Wonder what your response to that would be.
@@ukconstruction Simple for someone like your self but unfortunately I've never seen anything close to your stuff when I have a nosey at local roofing works. A breakdown of the costs when it's completed would be very interesting 👌
Hi Robin, beautiful work as ever! I have a 50 degree pitched warm roof to insulate and wondered how you calculate your hip and valley compound cut angles?
Robin, With a tight house like this, will a heat exchanger ventilation unit be installed? Thanks for the videos, I am not in the business but I still enjoy watching any master practice his craft. Plus, you seem like a nice guy.
Your parietooccipital cortex should have been working 24/7 on this project. What an inspirational dedication. BTW, what about chimneys? None in the project?
Any thing to think about if mounting PV on a warm roof? Do the fixings need to go through to the internal rafters? Can you do a general vid on the fixings that go through the insulation rafters? Calculating the spacings, the length, the angle they're inserted, figuring out the local wind factors...?
Great video, as usual. I’d love to see Robin move more into the biobased sphere. By now we all know the benefits of phase shifting, thermal inertia, etc, that PIR lacks. And the circularity that is lacking here. With such a craftsman at work, Robs efforts would be put to better use, making better buildings. If only the designer and client and material supplier would take the same fanatical approach, it would yield so much more. Come on Rob! Expand into real green building, it’s an exiting field with so much development still going on and innovation at much higher pace than the regular building practices.
Great video again Robin. I must admit I do miss your little music intro !! Because you have not used osb sheeting did you have to use more trusses ? Last time I did a roof the osb formed part of the loading specs etc so just wondered how this roof works specs wise thanks
Beautiful work! Shame to cover it up with the plasterboard and tiles 😂 Have a look into types of roofing underlays (LR, HR and Vapour permeable membrane which is commonly referred to as breather membrane). Will help clarify the requirements for ventilation (under membrane or under roof covering) and best way to install (onto insulation or above counterbattens). Membrane manufacturers such as Proctor have online webinars to help explain.
I’m assuming the rows of PIR aren’t glued / foamed to each other, with just seam taping outside won’t you get a slim cold spot at the joints that will be a condensation point for any vapour that works through?
We fit these tight together and the gap is minute as we are simply laying straight in a brick format, it is key that you start dead straight and parallel to the ridge!!
Scottish Building Regulations are already very different, but are changing again in January 2025, to full “Passive House” standard. Whether developer build, affordable homes or social housing.
Noce work looks much nicer thsn taking down lath and plaster and going home like a chimney sweep. Im thinking of looking into something like the hilti air cleaner to catch the airborne dust
The house has a sweater. What I thought in the British climate zone, you would dry an envelope to the outside - given the exterior tight insulation, and a tight barrier material covering the interior wall, moisture is trapped.
@Robin amazing work and attention to detail. The passion you have for your craft is so clear. I’m renovating my house, with a warm roof planned in, and I’m nearing the point where I need to find contractors (technical drawings nearly done). Based on your videos, my project probably doesn’t meet your minimum size requirements. Do you have any recommendations on how to find trustworthy tradespeople? I’ve been bitten a few times by the typical websites used to find trades people. What’s your thoughts on FMB for example?
Great video. We were trying to look for information or videos on warm roof construction and couldn’t find anything as comprehensive as this. In the end we went for a standard between and under rafter method due to this lack of information. However, the main things that held us back are as follows: Are the fixings driven in perpendicular to the roof or at a 30 or 60 degree angle? Once the battens are on, can they still support the weight of people walking/working on the roof? What was the reason for opting for insulation over and between, why not just go over the rafters only? Could there not be problems with interstitial condensation affecting the rafters?
Thanks for this detailed example, Robin, really appreciate the legwork you've done to make sense of the application spec differences. I've heard that PIR tends to shrink over time (due to things like off-gassing?). How is this accounted for in your 0.11 U value target & the design of the job? I've read about shrinkage anywhere between 1-2%.
The Use of Gapo Tape will allow for the minor shrinkage of PIR. Most boards by the time they make it onto site will have had enough time since manufacture to do any shrinkage or most of it, I have used some old stored sheets of PIR probably about 5 years old and they measured exactly 2400 by 1200 so no movement there, hope that helps
Somewhere in the system we have to have a cost/benefit discussion on residential insulation. Is all the costs of additional insulation worth it for the benefits which are measured in fractions of a watt. You would need scientific equipment to actually measure it. I doubt i would ever recoup these costs in lower bills. I am certainly not having a pop at you Robin, your work appears very high quality and I understand that you as a Tradesman follow the drawings as expediently as possible to make a living. Perhaps In a few years time i wont be able to enter my house because it is stuffed full of insulation and I have to sleep in the garage.. (I hope this is a joke..) More is not necessarily better.. 25mm of PIR does 80% of the insulating (From manufacturers blurb) The next 25mm adds another 5% diminishing..
Another universe compared to our 1970s bish bash bosh house, LBC Tudors laid frog down on weak mortar, no cavity wall insulation but loads of rubbish & mortar droppings, old tar roofing felt, paramount internal walls with the matching door linings/above door everglade glass panel. Rather have masonary over timbers & osb walls though, maybe a modern version of a cavity wall and then wet plastered/floated inside to prevent air leakage.
Hi Robin, great video, been watching a few as looking at a build in future. Quick question of warm vs cold roofs - if identical 200mm total (2 x 100mm) pir was used between rafters and either above or below rafters depending on if warm/cold roof, is either better from a energy conservation standpoint. I was wondering if colder than air temps due to heat lost via radiation in night sky on exposed rafters vs covered insulated rafters alters anything or if it did wether it’s negligible. Cheers!
I notice you have diagonal braces to strengthen the roof. If you wanted to plasterboard the loft space, would it be safe to remove these or would it mean you need a rigid sarking? For example a layer of osb on top of the rafters before the top layer of insulation, similar to a warm flat roof construction and your gable ends?
I would be very interested in the difference between this and the Gapotape you used on the big build as we have followed that route. Theis warm roof would not have worked for our project as the roof height would have needed to be higher. I wish our builder had your eye for precision as we had to remove all of the PIR he had installed and refit it to some sort of stnadard using gapotape.
@ukconstruction that would be great, I know companies all complaining about everyone expects the best and highest quality coupled with highest performance but absolutely no customer wants to pay for it
@ukconstruction are you taking on the role of Principle Designer (under the BSA 2022) on projects like this? Seems you are making key decisions about how to comply with the B'Regs which would normally sit with the architect, but at no point mention them. I'm not saying that's incorrect, just curious as there has been a lot of confusion & mixed advice on how to navigate this new system post Oct 2023.
With the added air flow on top is this not technically a hybrid warm/cold roof? As technically a warm roof has no ventilation & a vapour control layer to control/stop moisture vapour transferring to cold side of insulation.
How do the rafters dry out with with a vapour barrier above on the insulation and below on the plasterboard ? I appreciate this is the recommended method but it seems like ideal conditions for rot to set in.
![BOWKYLION - วิงวอน (ex-change) [Official MV]](http://i.ytimg.com/vi/cLdnZWDaO-w/mqdefault.jpg)
This isn’t building….. it’s engineering! Robin, you are a master and thank you for sharing your skills and expertise with us!
Good building incorporates good engineering and that is what is mostly missing in house building.
Robin's understatement of the week, "I'm a bit of a fanatic".
An absolutely fantastic Robin Clevett video. Such high quality information. Thanks
The quality on show here is legendary!
It says "chippy" on your back, but you are so much more. Exceptional work!
Fantastic..... I'm a bit further down the road with my, almost identical build. If ever the phrases, "the Devil is in the detail" and "planning is everything" come to the fore...... this is it...... So many peeps in the trade can't get their heads around this.....
Trade just haven't spent enough time figuring out what works well and what doesn't work well with warm roofs. They will get there, but it's early days. So good to see Robin sharing his ideas for how to do it well. The energy efficiency of the finished home is well worth the ttime spent getting the design right.
perfect planning prevents piss poor performance . The 6 P's
@@andrewpritchard5328 In the Military It was the 7P`s = "Perfect - Pre - Planning - Prevents - Piss -Poor -Performance."
and if you failed at a task it was the 4 F`s = "Found it, Flaked it, Failed it, Fuck it."
👍🤔
Any thing to think about if mounting PV on a warm roof?
Can you do a vid on the fixings that go through the external rafters? Calculating the spacings, the length, the angle they're inserted, figuring out the local wind factors...?
You are incredible Robin. Outstanding work, as always!
Robin is a genius!
Amazing job Robin, Well Insulated roof once again, keep up the good work 👍😃
Thanks again!
Some grilled chicken and watching the master at work! Life’s good !! 😂, absolutely incredible as usual! Well done rob .
Gosh 😅 this is Art !!!
I feel honoured to watch your videos, excellence and dedication!
Thank you so much 😀
Your wee jigs are a great addition.
Glad you like them!
Outstanding workmanship Robin, very thoughtful construction and detailing. I’d love a roof like that! 🙂
Thank you kindly
That’s very impressive Robin. Really beautiful work, they’ll get the dividends back in the future when they rarely have to use the heating!
Really enjoy your videos, it's great from an architects point of view to see someone who is great at what they do and highlights where buildability issues crop up - super useful as it's hard to predict these issues on a drawing board.
I would class this as a Hybrid roof because you have introduced a ventilation on top of the insulation, a warm roof for me is when the finish product is fitted directly to the insulation.
Hybrid is where there is a gap between the cold insualtion and the warm risking interstitial condensation.
As I see it, a 'warm roof' would have all the insulation above the rafters. How you would/could do that I don't know.
@@davidscott3292 It can be done, with the primary battens nailed through the insulation. One must be mindful of the fixing detail as the 150mm insulation doesn't really 'support' the fixing so the weight of the tiles and wind uplift calcs must be considered.
Robin love the video, amazing craftsmanship detail detail detail love it, but how on earth do you even price a job this size, a video on how you price a job like this would be beneficial, amazing 👍💪
Great point! will do a video in the future
Loved that vid. So neat, tidy and well thought out. Great care taken. Fantastic
Attention to Detail on PIR......Love it
Exemplory work. Lucky Clients!
I'm a bit of a fanatic too. A building control officer said to me once, "come on we're not building a spaceship". We I think we are now..! Every insulation,and membrane manufacturers specification are different....
Easy to get headaches these days
Love the idea of the sprocket. I've been looking at warm roof design for a while but never see this detail.
Great videos and out on his own in construction.
We've just finished a warm roof on an old oak barn, we done the same as you. Out the felt ontop of the counter battens
It's beautiful....like a teapot!
Always incredible work Robin 👌
Thank you very much!
Robin that's great work pir is a hard material to get precise so many don't but that must have been an impossible job to price measuring cutting fitting tapig and then battons hope whoever lives there appreciated the detail
Great looking build. Good to hear the reasons for the different insulation cutting methods as well
Glad you like it
Great vid Robin , bet that Festool insulation saw got a good workout
Absolutely
I like it, especially for that type of build 👍
that's such a nice roof, i would just leave it open from the inside, so can look at it every night 👌😁
Wow, that looks like some tricky work going on there. You do make it look easy though. Thanks for sharing.
Brilliant video again Robin! I’ve learned so much and looking forward to the next one. Thanks mate 👍👍
Great to see quality work with well thought out detail. Keep posting these informative and knowledgeable vids. I’m sure younger people entering the trade benefit from your years of experience. Devil is in the details! Unfortunately customers are sometime persuaded that Price is the crucial element. Quality work, strong detailing lasts longer and is more efficient over time. 👏
Great workmanship really impressive
Thank you! Cheers!
Wonderful to see and thank you for sharing. My only gripe is that the dormers are being done as a cold roof, which is a shame given the insulation levels to the rest of the roof, but it certainly doesn't detract from the precision work you have here, it's great to see!
Outstanding! Congratulations on your success. In my opinion that is a world leading structure.
In your follow up video could you go into the cross flow ventilation to the rafter. You mentioned an over fascia vent which i imagine is purely for the counter lath. Your soffit i imagine is going to be vented on the eaves and you have a detail in the ridge to complete the ventilation down to the rafter.
I don’t no what to say about that other than slightly insane and also amazing ,I’m torn
Another great video Robin. If only we could clone you a few thousand times we'd have a chance of the new builds lasting something like the length of time the Victorians expected and also only costing a few hundred pounds a year to heat. Every job I do I find myself asking, how would Robin do this ? Bravo Robin and keep up the great work.
I wish I knew half of what you know regarding building your top of the game mate
Actually just did a bit of searching and you can get an eaves closure piece that fits under the GRP valley at eaves level, looks very neat but like most things it might be a bugger to fit in real life.
An artist. Wonderful.
Kinda strange seal everything up ,warm roof then go and add cold air albeit above insulation ,cold side it’s all getting a mine field to understand but great work as always
Excellent video robin
A master piece of a structure. Well done Robin.I believe you should express all your lineal dimensions,in it's imperial equivalent for the benefit of USA subscribers.
I try John!!
I know Rob you are a gentleman
I'm planning a self build with a mono pitch roof... Sadly, I won't have the opportunity to compete with Robin's cut precision 😳🥵😂
Hi Robin. I hope you registered the IP for the attachment for the ISC240. Then you can sell the license to Festool. Should be pretty easy to manufacture out of plastic/metal plate, but I would leave them to figure that out and just get them to pay you a license for each one sold. Easy money. Might not be as much as manufactoring it yourself but the pennies add up to pounds.
Market is small. probably cost me more in fees that I would get back. I have one that we have prototyped that is adjustable so keep tuned!!
I contacted building control to ask what my local regulations are (as I moved up the other end of the country) I was told work done would need to be to the Building Regulations 2010 as would be applicable anyway in the England.
Excellent insulation values, though missing a key component for the envelope, vapor diffusion. Typically in cooler climate zones vapor pressure drive is outward. The interior OSB is enough of a vapor restrictor to inhibit this outward drive. The foil faced exterior is a vapor barrier on the wrong side, inhibiting outward vapor diffusive drying. And does very little to control heat transfer. Cold climate research shows the exterior radiant barrier only reduces heat transfer by 2%, though blocks vapor on the cold side.
More important to stop air flow with continuous membranes that are permeable and liquid water tight.
You need to get a new shirt, changing chippy to craftsman on your back, how you can setout and cut in 3D (with a PIR offset), is amazing.
Proper job.
Superb job
Thank you Martin
Seriously impressive ❤
Lovely work again Robin. Lots of work to do from the looks of it, how many guys would you have working with you on the joinery on a job like this? Thanks
Thing of beauty. So nice to not see steel in the two roofs I’ve seen you do on TH-cam. I’ve tried to convince two contractors I work with to investigate your method and they’ve dismissed it as too expensive. Wonder what your response to that would be.
nice one. such a neat job.
Thank you very much!
Great job Robin. I always think of you as the thinking man's chippy and this job proves it😂
Stunning work as ever Chap.... Thermal bridging from fixings and Any metal work?
Fairly minimal and taken into consideration by the Insulation manufacturer when calculating the values
Proper job 💪
Membrane over the counter Batton for me also :-)
Mind blowing work 🤯(I have a feeling the roof comes with an equally mind blowing price tag 😆)
No mate simple work and just to current regs, at the end I will do a cost for it
@@ukconstruction Simple for someone like your self but unfortunately I've never seen anything close to your stuff when I have a nosey at local roofing works. A breakdown of the costs when it's completed would be very interesting 👌
Hi Robin, beautiful work as ever! I have a 50 degree pitched warm roof to insulate and wondered how you calculate your hip and valley compound cut angles?
Amazing. Do roofers like it if you send them a Robin Clevitt video and say "quote for that"? (I assume RC is booked up for years in advance)
Robin,
With a tight house like this, will a heat exchanger ventilation unit be installed?
Thanks for the videos, I am not in the business but I still enjoy watching any master practice his craft. Plus, you seem like a nice guy.
insane regulations
This chap knows his, "shit-from-his-shovel."
Not half bad - that.
In USA they have termed it (Monopoly Framing). With a house this tight you will incorporate an air handling unit?
Any chance you can do a video on buying timber please? What types there, grades, what to look out for and what different use cases are?
Your parietooccipital cortex should have been working 24/7 on this project. What an inspirational dedication. BTW, what about chimneys? None in the project?
Any thing to think about if mounting PV on a warm roof? Do the fixings need to go through to the internal rafters?
Can you do a general vid on the fixings that go through the insulation rafters? Calculating the spacings, the length, the angle they're inserted, figuring out the local wind factors...?
Great video, as usual. I’d love to see Robin move more into the biobased sphere. By now we all know the benefits of phase shifting, thermal inertia, etc, that PIR lacks. And the circularity that is lacking here. With such a craftsman at work, Robs efforts would be put to better use, making better buildings. If only the designer and client and material supplier would take the same fanatical approach, it would yield so much more. Come on Rob! Expand into real green building, it’s an exiting field with so much development still going on and innovation at much higher pace than the regular building practices.
I am always looking into this!!
Great video again Robin. I must admit I do miss your little music intro !! Because you have not used osb sheeting did you have to use more trusses ? Last time I did a roof the osb formed part of the loading specs etc so just wondered how this roof works specs wise thanks
Beautiful work! Shame to cover it up with the plasterboard and tiles 😂
Have a look into types of roofing underlays (LR, HR and Vapour permeable membrane which is commonly referred to as breather membrane). Will help clarify the requirements for ventilation (under membrane or under roof covering) and best way to install (onto insulation or above counterbattens). Membrane manufacturers such as Proctor have online webinars to help explain.
I’m assuming the rows of PIR aren’t glued / foamed to each other, with just seam taping outside won’t you get a slim cold spot at the joints that will be a condensation point for any vapour that works through?
We fit these tight together and the gap is minute as we are simply laying straight in a brick format, it is key that you start dead straight and parallel to the ridge!!
Incredible
😊
Scottish Building Regulations are already very different, but are changing again in January 2025, to full “Passive House” standard. Whether developer build, affordable homes or social housing.
So no affordable housing then :)
@@xbgo1856we're doing it in Wales now aswell , the spec of housing association builds are ridiculous,
Noce work looks much nicer thsn taking down lath and plaster and going home like a chimney sweep. Im thinking of looking into something like the hilti air cleaner to catch the airborne dust
The house has a sweater. What I thought in the British climate zone, you would dry an envelope to the outside - given the exterior tight insulation, and a tight barrier material covering the interior wall, moisture is trapped.
Would love a step by step video on how you make the jigs for the festool saw robin 🙏🏻
OK Liam will sort something
@@ukconstruction top man
@Robin amazing work and attention to detail. The passion you have for your craft is so clear.
I’m renovating my house, with a warm roof planned in, and I’m nearing the point where I need to find contractors (technical drawings nearly done). Based on your videos, my project probably doesn’t meet your minimum size requirements. Do you have any recommendations on how to find trustworthy tradespeople? I’ve been bitten a few times by the typical websites used to find trades people.
What’s your thoughts on FMB for example?
Great video. We were trying to look for information or videos on warm roof construction and couldn’t find anything as comprehensive as this. In the end we went for a standard between and under rafter method due to this lack of information. However, the main things that held us back are as follows:
Are the fixings driven in perpendicular to the roof or at a 30 or 60 degree angle?
Once the battens are on, can they still support the weight of people walking/working on the roof?
What was the reason for opting for insulation over and between, why not just go over the rafters only? Could there not be problems with interstitial condensation affecting the rafters?
Thanks for this detailed example, Robin, really appreciate the legwork you've done to make sense of the application spec differences. I've heard that PIR tends to shrink over time (due to things like off-gassing?). How is this accounted for in your 0.11 U value target & the design of the job? I've read about shrinkage anywhere between 1-2%.
The Use of Gapo Tape will allow for the minor shrinkage of PIR. Most boards by the time they make it onto site will have had enough time since manufacture to do any shrinkage or most of it, I have used some old stored sheets of PIR probably about 5 years old and they measured exactly 2400 by 1200 so no movement there, hope that helps
Somewhere in the system we have to have a cost/benefit discussion on residential insulation.
Is all the costs of additional insulation worth it for the benefits which are measured in fractions of a watt.
You would need scientific equipment to actually measure it. I doubt i would ever recoup these costs in lower bills.
I am certainly not having a pop at you Robin, your work appears very high quality and I understand that you as a Tradesman follow the drawings as expediently as possible to make a living.
Perhaps In a few years time i wont be able to enter my house because it is stuffed full of insulation and I have to sleep in the garage.. (I hope this is a joke..)
More is not necessarily better.. 25mm of PIR does 80% of the insulating (From manufacturers blurb) The next 25mm adds another 5% diminishing..
Another universe compared to our 1970s bish bash bosh house, LBC Tudors laid frog down on weak mortar, no cavity wall insulation but loads of rubbish & mortar droppings, old tar roofing felt, paramount internal walls with the matching door linings/above door everglade glass panel. Rather have masonary over timbers & osb walls though, maybe a modern version of a cavity wall and then wet plastered/floated inside to prevent air leakage.
Hi Robin, great video, been watching a few as looking at a build in future. Quick question of warm vs cold roofs - if identical 200mm total (2 x 100mm) pir was used between rafters and either above or below rafters depending on if warm/cold roof, is either better from a energy conservation standpoint. I was wondering if colder than air temps due to heat lost via radiation in night sky on exposed rafters vs covered insulated rafters alters anything or if it did wether it’s negligible. Cheers!
Great video!!!
Cheers Sam!!
Never done a warm roof. How do you fix the insulation to the top of the Spars? Tac them, then fix a vertical lat on top through it and into the Spar?
I notice you have diagonal braces to strengthen the roof. If you wanted to plasterboard the loft space, would it be safe to remove these or would it mean you need a rigid sarking? For example a layer of osb on top of the rafters before the top layer of insulation, similar to a warm flat roof construction and your gable ends?
now that`s a warm roof
nice work a little different from the big build, Another question where is Ed did he start his own company?
I would be very interested in the difference between this and the Gapotape you used on the big build as we have followed that route. Theis warm roof would not have worked for our project as the roof height would have needed to be higher. I wish our builder had your eye for precision as we had to remove all of the PIR he had installed and refit it to some sort of stnadard using gapotape.
Robin, Do you seal the PIR external joints with tape as you did at the top please?
Yes Peter
It would be good to see exactly how many hours labour goes in to everything including the eaves details
I am going to do a video on the whole roof cost from wall plates to fully insulated up to the tiling and I will break that down into man days etc
@ukconstruction that would be great, I know companies all complaining about everyone expects the best and highest quality coupled with highest performance but absolutely no customer wants to pay for it
@ukconstruction are you taking on the role of Principle Designer (under the BSA 2022) on projects like this? Seems you are making key decisions about how to comply with the B'Regs which would normally sit with the architect, but at no point mention them. I'm not saying that's incorrect, just curious as there has been a lot of confusion & mixed advice on how to navigate this new system post Oct 2023.
just looking at the craftsmanship of the woodwork, it seems a crime to cover it in plasterboard
Hi Robin. When we do warm flat roofs we have to put the vcl between the bottom deck and the pir. Where are you putting the vcl in your pitched roof?
With the added air flow on top is this not technically a hybrid warm/cold roof? As technically a warm roof has no ventilation & a vapour control layer to control/stop moisture vapour transferring to cold side of insulation.
How do the rafters dry out with with a vapour barrier above on the insulation and below on the plasterboard ?
I appreciate this is the recommended method but it seems like ideal conditions for rot to set in.
We used sf40 as the over insulation much thinner
That's a very expensive roof! Lovely mind. Do you think they will have problems with the building sweating inside?
Not at all, we will have MVHR here
Given how time consuming it is to fit insulation between the rafters, how badly would reduce your U value if you had full fill Rockwool batts