Insulating a Warm Pitched roof to new regulations 2024

[@thomhollands]

This isn’t building….. it’s engineering! Robin, you are a master and thank you for sharing your skills and expertise with us!

[@clivewilliams3661]

Good building incorporates good engineering and that is what is mostly missing in house building.

[@cliveramsbotty6077]

An absolutely fantastic Robin Clevett video. Such high quality information. Thanks

[@geoffcroft9439]

Robin's understatement of the week, "I'm a bit of a fanatic".

[@raymondjackson-h3u]

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

[@BitsnBobs-hk5iy]

It says "chippy" on your back, but you are so much more. Exceptional work!

[@hifiandmtb]

The quality on show here is legendary!

[@togarchitecture]

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.

[@scottwood1562]

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.

[@MikeMason1]

You are incredible Robin. Outstanding work, as always!

[@Florin_Bolocan]

Gosh 😅 this is Art !!! I feel honoured to watch your videos, excellence and dedication!

[@ukconstruction]

Thank you so much 😀

[@DIYLONDON]

Some grilled chicken and watching the master at work! Life’s good !! 😂, absolutely incredible as usual! Well done rob .

[@marklawlor9355]

Amazing job Robin, Well Insulated roof once again, keep up the good work 👍😃

[@ukconstruction]

Thanks again!

[@samposton9101]

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!

[@denty32]

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.

[@ndewhurst1007]

Hybrid is where there is a gap between the cold insualtion and the warm risking interstitial condensation.

[@davidscott3292]

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.

[@ndewhurst1007]

@@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.

[@mikepowell5254]

Outstanding workmanship Robin, very thoughtful construction and detailing. I’d love a roof like that! 🙂

[@ukconstruction]

Thank you kindly

[@BerkeleyTowers]

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.....

[@tlangdon12]

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]

perfect planning prevents piss poor performance . The 6 P's

[@martin2466]

@@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." 👍🤔

[@andypag1071]

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...?

[@stillasgoodasnew]

In the summertime I would hate to be living in that space way to hot

[@martindownward9253]

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

[@mikevolante7663]

Fantastic job. Big thanks for sharing your experience and expertise

[@ukconstruction]

Glad you enjoyed it!

[@philipwilliams8114]

Loved that vid. So neat, tidy and well thought out. Great care taken. Fantastic

[@ramhomes9074]

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

[@bapsmcginty4782]

Your wee jigs are a great addition.

[@ukconstruction]

Glad you like them!

[@paulminns2937]

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. 👏

[@harrylenton9984]

Great looking build. Good to hear the reasons for the different insulation cutting methods as well

[@ukconstruction]

Glad you like it

[@alexanderbennie4819]

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 👍💪

[@ukconstruction]

Great point! will do a video in the future

[@tlangdon12]

Love the idea of the sprocket. I've been looking at warm roof design for a while but never see this detail.

[@bobbrown2143]

Attention to Detail on PIR......Love it

[@elliejake11]

I like it, especially for that type of build 👍

[@SteveStevieboy]

Brilliant video again Robin! I’ve learned so much and looking forward to the next one. Thanks mate 👍👍

[@timquirk7551]

Some brilliant details, now to save up for that festool.

[@tommyknightly1659]

Great videos and out on his own in construction.

[@amunderdog]

In USA they have termed it (Monopoly Framing). With a house this tight you will incorporate an air handling unit?

[@leeedwards3783]

Wow, that looks like some tricky work going on there. You do make it look easy though. Thanks for sharing.

[@scottprovost5029]

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.

[@Rudhamstile]

Exemplory work. Lucky Clients!

[@videogalore]

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!

[@paulradwell9719]

It's beautiful....like a teapot! Always incredible work Robin 👌

[@ukconstruction]

Thank you very much!

[@brucecrowther1104]

Robin is a genius!

[@speedbird300]

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?

[@ukconstruction]

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!!

[@JurassicJungle]

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.

[@Alexxx---101]

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.

[@yolomc2]

that's such a nice roof, i would just leave it open from the inside, so can look at it every night 👌😁

[@JustLikeBuildingThings]

An artist. Wonderful.

[@nickhaley4663]

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.

[@andypag1071]

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...?

[@richardgatehouse1520]

Great vid Robin , bet that Festool insulation saw got a good workout

[@ukconstruction]

Absolutely

[@marksmith3267]

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.

[@steverathbone1954]

Hi Robin Thank you for your Amazing video's on your construction work could you give me the approximate span of floor width and length and pitch of the roof. Thanks again.

[@SME_Ste]

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

[@mattygiggity]

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?

[@thejtizzel]

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?

[@MarlonKingShow]

That insulation looks sound. I noticed tripple and quadruple beams used on main support parts. Is this a common replacement instead of using steal which tends to be recommended on most loft conversions these days?

[@ianbutler1983]

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.

[@daves4026]

We used sf40 as the over insulation much thinner

[@mosttwisniewski5476]

Great workmanship really impressive

[@ukconstruction]

Thank you! Cheers!

[@adriannewton8832]

Thing of beauty. So nice to not see steel in the two roofs I’ve seen you do on KZbin. 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.

[@Darrida]

What is SD value of air membrane in your roof? Or there will be only plasterboard inside?

[@mannatuu]

Yet at the gable end you are effectively creating boxes . so what about the through ventilation up the gable length?

[@stuartrowe3006]

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.

[@ukconstruction]

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!!

[@voodoomotion5855]

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?

[@johnchincotta1qwdb15]

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.

[@ukconstruction]

I try John!!

[@johnchincotta1qwdb15]

I know Rob you are a gentleman

[@scotteric8711]

I was looking for a more efficient way to rebuild my roof in the US. Thank you for this video! Europeans are always at the edge of better architecture, not simply the cheapest. Do you have a video on insulating a roof with exposed dovetails at the gables?

[@PaulMason1986]

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?

[@TechOne7671]

Proper job.

[@neillambourne6503]

Love your videos Robin. Brilliant stuff. I'm about to build a garden room and I really want a pitched roof. I'm also a big fan of warm roofs in general. Is this setup a hybrid roof though? My understanding is that if the majority of the insulation is above the rafters then the dew point shouldn't get near the structural element of the roof. Did the engineer roof desiger touch on this? Many thanks

[@Joe74854]

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

[@ianstockdale964]

Excellent video robin

[@A_Viewfinder]

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?

[@memyselfandeye1234]

Stunning work as ever Chap.... Thermal bridging from fixings and Any metal work?

[@ukconstruction]

Fairly minimal and taken into consideration by the Insulation manufacturer when calculating the values

[@opentrail]

Fabulous detail Robin. Are there are considerations for fitting solar panels on this or other Warm roofs?

[@ukconstruction]

They can be fitted in the same way as you would for a cold roof, it may just be longer fixings if you are anchoring to the rafters

[@EverydayLife621]

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.

[@MrAidanfleming]

Seriously impressive ❤

[@itfc3]

nice one. such a neat job.

[@ukconstruction]

Thank you very much!

[@JohnSmith-zy1ur]

Outstanding

[@snookluvr2913]

I’m a bit confused. Does the Recticel have shear value? Typically in the US, the underlayment would be fastened directly to the roof rafters. The insulation would be installed over the underlayment which acts as the roof diaphragm. There would be a second layer of underlayment over the insulation that would be fastened to the batten strips. How does your roof diaphragm work? Thanks.

[@ukconstruction]

Our roof structures are designed that the main timber work frame including all the structural trusses, lattice ridges and other components perform to make the structure rigid and strong, the insulation here plays no part in the design other than for thermal properties, It does however by default once its all laid square and tight over the roof structure and clamped down by the counter batten add to rigidity, hope that answers your interesting question?

[@andrewbrennand4945]

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!

[@markturner6091]

Very impressive…….

[@philbooth319]

​@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.

[@miantamoorsaleem8287]

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?

[@skiiddy]

Higher U value. Target was 0.11. Part L requires 0.15 so this far exceeds minimum and is probably at passive house standard.

[@blackhouseengineering5386]

Great job Robin. I always think of you as the thinking man's chippy and this job proves it😂

[@pinlap3875]

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%.

[@ukconstruction]

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

[@peterwalton1502]

Robin, Do you seal the PIR external joints with tape as you did at the top please?

[@ukconstruction]

Yes Peter

[@therabman_5606]

I wish I knew half of what you know regarding building your top of the game mate

[@leonpetersen3572]

I don’t no what to say about that other than slightly insane and also amazing ,I’m torn

[@DavidSmith-do6ji]

Membrane over the counter Batton for me also :-)

[@cowz47]

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.

[@ukconstruction]

I am always looking into this!!

[@Rogerdodger-z7x]

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.

[@dailysleaze]

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)

[@frantiseksram9741]

What's a job like this costing on existing building?

[@80adrian80]

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

[@Samfarrelly]

Proper job 💪

[@Dr.CandanEsin]

Your parietooccipital cortex should have been working 24/7 on this project. What an inspirational dedication. BTW, what about chimneys? None in the project?

[@skiiddy]

Hi Robin, avidly followed you since you started posting and this video coincidentally coincides with a similar roof we are contemplating on a large extension. Couple of questions if you don’t mind: Do you cover the rafters with any OSB or Ply followed by a breather membrane and then the insulation or does the insulation sit directly on the rafters? I’m trying to get my head around how you ensure no wobbly insulation as the rafters are probably only 50mm wide ? Thank you.

[@nautilusshell940]

insane regulations

[@muddy11111]

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.

[@Me1234utube]

I do get concerned that manufacturers only give broad recommendations, later down the line their will be rot problems where the process has been misunderstood or poorly installed , try figuring out what membranes do when vague terminology is used .

[@crishill6458]

It would be good to see exactly how many hours labour goes in to everything including the eaves details

[@ukconstruction]

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

[@crishill6458]

@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

[@peterkavanagh3296]

Robin, have you done any full spec Passive House??

[@gordonmackenzie4512]

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.

[@xbgo1856]

So no affordable housing then :)

[@pauldavies7251]

​@@xbgo1856we're doing it in Wales now aswell , the spec of housing association builds are ridiculous,

[@todc8986]

nice work a little different from the big build, Another question where is Ed did he start his own company?

[@liamleech6844]

Would love a step by step video on how you make the jigs for the festool saw robin 🙏🏻

[@ukconstruction]

OK Liam will sort something

[@liamleech6844]

@@ukconstruction top man

[@1_MartinFlanagan]

Superb job

[@ukconstruction]

Thank you Martin