How To Insulate A Warm Loft 

My latest series - 1100 to 3000 Sq ft house - ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-jYrWMxWvGvc.html My Instagram - instagram.com/youtube_reno?igshid=YmMyMTA2M2Y= 00:01 - What the project is 02:12 - Cost of insulation 03:16 - How to fit 06:16 - Walk around of where I will be insulating 08:48 - Time lapse of insulating the rafters with 100mm insulation 12:47 - Time lapse of insulating over the rafters and plasterboarding 15:00 - Walk around of progress so far 19:05 - Time lapse - insulating between the walls 19:42 - Plasterboarding 90% complete 24:08 - The finish!

One normal person who showed how to do it right from beginning to end. thanks. very helpful. there were a lot of questions but after your video I got answers to everything I didn’t know

Where is the vapour barrier ?

Should have cut the xtratherm small and used gapotape. There would then be no gaps anywhere to fill or any need to shave the sides.

Where you cut a.little short, gapotape was a solution for me, and it reduced any small gaps there might be

You should also tape all the joints. See Skill savers.

Gorgeous space, Nick. You are so very talented and not afraid of taking in a project. I have immense respect for you. You’re welcome to come and stay with us in the US if you ever want to take in another project. Lol.

The 50mm gap is not to do with “cold bridging”; this is where you get heat conduction through a less insulating part. E.g. the rafters could be a cold bridge from the roof to the ceiling (the overlay of the thinner layer minimises this). The 50mm gap is for ventillation, as long as you have air gaps in the soffit.

It is very advisable to install some battening onto the fathers to ensure that the insulation does not move. Also as of June this year a product called gapotape is required, it completely fills any discrepancies between the insulation and rafters.

Well, that might work down there where you don't have minus 25 celsius in winter! Othervice you should put foam between the insulation and the truss and also " glue ends of insulation together with foam so there will be no leak at all! Here up north we cut the insulation board about half inch in both sides so we get foam as deep as the insulating board goes. Makes it solid and keeps the isolation on the right place.

Well illustrated work. I'm impressed you got a friction-fit good enough to not have the PIR falling out from betweeen the rafters. I would have had to be using 100ml tape along the rafters to catch and hold the board either side of each until the 20mm cross-boarding held them in place. Do you have ridge vents at the top of the air gap outside the between-rafter insulation, and were there any particular tricks to prevent them being blocked by the rockwool when pushing it up under the ridge board? Maybe you carried the PIR right up to the ridge board - I couldn't see.

Really helpful to see this video - I've not seen anyone give such a clear and detailed video on this subject. Its credible and gives me confidence. I'm about to undertake a loft conversion in my bungalow in Scotland and will definitely be using this as a guide.

HE BODY , WHEN YOU ARE SPEAKING THE SOUND IS VERY LOW . WHEN IT IS THE MUSIC VERY TOO MUCH HIGHT . PLEASE FOR NEXT TIME . I AGREE YOUR INSTALLATION . THANK

I feel like the building inspector didn't know what they were talking about. I'm only a DIYer, but I can't see why you'd have to leave a 50mm gap at the back of the uprights... The gap is for airflow, and as you've pointed out, there's a huge gap behind the wall. 100mm insulation wouldn't have hurt. Also, where the top of the dwarf wall meets the rafters you have a beam installed at an angle that matches the rafters. I've read that it's better to cut a birdsmouth in the rafters and to have the beam laid horizontally on the uprights. This way the loading from the roof is purely vertical and doesn't rely on the strength of the fixings at all.

£40 per sheet, now I know why I see so many security videos on twitter, showing this stuff being stolen from building sites.

Thank you. I am thinking of doing a loft conversion at home myself. This really helped me visualise it.

Nice informative video Nick. Off topic but can I ask what video editing software you use? Cheers.

Hi Nick, some years ago when i lived in Finland i had the opportunity to help on an insulation project they used 150mm rigid foam foil front & back & left a 50mm air flow gap - they cut all PIR 10mm undersized ( allowing a 5mm gap on both sides ) a short batten screwed into each rafter was used to support the PIR & pull it forward & keep it in place using a screw ( when placed between the rafters ) the gap was filled with a foam injection gun on all sides - screws on the support batten pulled the PIR to the face of the rafters - no hammering on the PIR to get it in place - when the injection foam was cured the excess was cut away leaving a perfect airtight fit - the whole project was very fast & easy. Ed,

Well done for tackling this...it will have saved you a pretty penny no doubt. 👏👍🥳

Thank you Nick for such a detailed video. im off to get some materials and get to work. Thank you very much

Thanks for the vid Nick. We're currently renovating an 1895 stone built house in Switzerland and loft insulation is one of our main topics for 2023. Your video has been a great help towards sorting my head out with what I need to do.

You could have fixed your knee wall insulation on the inner side without any cutting.

Spot on Nick, really helped with my loft conversion in a similar aged bungalow.

I would of ran that foam board horizontally. That would of insulated the rafters as well and provided a larger air gap between the roof deck and the foam boards. Install a roof ridge vent and soffit vent boards.

Thomas Carol Walker Michael Hernandez Anna

Beautifully done! Thank you for the video, it has been very helpful.

I absolutely hate pir insulation 😅😂 I did ground area 70-80sqm of pitched roof which is 100mm between the rafters and 50mm overboarded for the cold bridge. My advice is get someone else to do it 😂

Clark Kenneth Walker Charles Miller Scott

Great video. Really helpful, can you confirm if the 100mm was used between the studs for the walls you don't need to carry the rafter insulation down to floor level? I was hoping to do a cold loft on the outside of the room

This year they added Gapotape to seal edges as Part L.

No air-tightness measures. That’s a major omission. As a wetsuit works with water, insulation functions by trapping air. A membrane should have been installed behind the rigid board. All holes in the cold attic (downlighters, piping, sockets) should have been air-tightened. Draft causes 5x heat loss compared to conduction.

Thanks for the video Nick. Looks fantastic - now enjoy!

"Must use professionals"....lol....about 30-40% of ALL British builders/trades are somewhere between good to excellent, the rest are below average to utter rubbish. MY understanding of cold bridging is when warm can travel through materials to the outside?

Pizza slice cuts insulation board well with no mess, don’t need to cut right through, snaps along the cut like plaster board. 👍

I haven't been able to watch the entire vid yet, but my garage roof and walls needs insulating, so I guess it would be the same method and principles outlined in this vid?

Why would you need to insulate a warm loft? (I’ll see myself out!)

Thanks for the GREAT video! If you have a minute... I have a roof with only tiles then felt. Should I put anything between the felt and the installation board? Cheers for your time either way.

Hi great work, currently renovating a similar age property, where do you recommend buying radiators ? Thanks

Great video. Ventilation behind the insulation, how does the air enter and leave. Are there vents in the eaves and vent tiles in the roof

Great! So does that give the sufficient U value? I would have though deeper would be required? Many thanks.

Thanks for the video. What is exactly the name of the product you use, please?

Can you put a video for how to do wiring for the loft conversion as well please?thanks

Hi Nick, Great work! Lovely to watch. My reg's here (DK) require an additional 25mm air gap between the foam insulation and then two layers of 12.5mm plasterboard. I guess there's no air gap requirement on the inside of the sheet rock in the UK?

100 mm Rockwool would be much cheaper?

Di you put insulation on the copper pipe work?

*Summary of Nick's Home Renovation Video* Nick, an electrician by trade, shares a how-to video on insulating a warm loft in a 1936 bungalow renovation. He emphasises that with guidance and advice, anyone can do the job themselves and save money. Insulation Process - Rigid Insulation: Nick uses 100mm rigid insulation between the rafters, ensuring a 50mm gap for air flow to prevent cold bridging. - Cost and Labour: Rigid insulation costs around £40 per sheet, and Nick recommends doing the job yourself to save money. - Installation Tips: Nick advises wearing appropriate PPE, leaving a 50mm gap between insulation and rafters, and ensuring a tight fit. Additional Insulation - Mineral Wall Insulation: Nick explains insulating mineral walls, recommending using 100mm insulation for better heat retention. - Ceiling Insulation: Nick insulates the floor and ceiling below to keep the space warm. Completion of the Project - Plasterboarding and Finishing: Nick shows the process of plasterboarding and finishing the loft space, creating a warm and well-insulated room. - Final Result: After two weeks of work, Nick successfully completes the bedroom and ensuite renovation, demonstrating that DIY insulation is achievable with proper care and attention. Nick provides valuable insights and practical tips throughout the video, making DIY insulation accessible to viewers. but *List of materials used* - 100mm Rigid Insulation: Used to insulate between the rafters. - Mineral Wall Insulation: Insulated walls for better heat retention. - Plasterboard: Used for finishing and covering the insulation. - Expanding Foam Tape: Used to seal gaps. - Urethane Sealant: Used for sealing gaps. - Hammer: Used for installation. - Ear Defenders: Used for protection. - Safety Mask: Used for protection while handling insulation. - Goggles: Used for eye protection. - Gloves: Used for hand protection.

WOW! £40 per sheet!! 2:16 Sounds like a bargain now, just ONE YEAR LATER its more like £90 per sheet!! Gotta love that 'Covid tax'!!

Hi Nick, I have a dilemma and I wouldn’t mind getting your views. I am in the process of converting my loft and the structural engineer suggested to only submit a building notice application instead of full plans application. Do u think that this is a good idea? Are there any risks with building notice only applications?

Nice work! I am working on the same project. How much insulation material used for this project?

Can this same method work between floors? I.E between a ceiling and first floor? Thanks I’m advance

Great video, full of really useful info 👌

Brilliant Vid. Excellent explanation throughout!!

Are you walking on OSB board or wood board? What's the thickness? What's this kind of roof structure called?

per fit how mace

Your amazing 👏 thank you and your right about doing it yourself

Great job, many thanks for showing such a detailed process. 👍

Sorry i ment say Skill Builds

You mentioned to leave 50mm gap. What if the rafters are small? My rafters are 3 inch (76mm) in depth. What thickness of cleotex or rigid board do you recommend and how much gap should I leave? Thanks

Shame to have all that space under the eaves and not utilised for cupboards and storage, otherwise great job thanks!

100mm rigid insulation is the equivalent of 200mm of fibreglass,hence the price

Great video ty.

At last a video showing you how to do a job without the person promoting some rubbish or other. Well done mate a very good video. If you can, can you do some on electrical work. like wiring in a she that's at the bottom of the garden

This was really helpful thank you

Good work apart from now running second layer all the way up also yolu should have foil typed all. Joints.

Nice video! Very helpful.

Really nice video but just a have a question about why you've called it a warm loft but its actually a cold roof install?

Always wondered how it was snug fitting, cut a couple of mil over mark ?

how have you insulated the boarded part you're walking on ??

Excellent what about this loft floor any insulation on the walking space of the room thanks

One Thing to ask you is Xtratherm is that Fireproof?

Hi Nick I have a single skin wall at the back of the house that I need insulating internally do you know whether I need the same 100mm insulation and 50mm air gap the same as it is for the ceilings you’ve done? Thanks

Would it make my house or attic on summer because my house is a oven in summer, ive to use air con in Ireland, dont why it gets so warm compare to other houses do be cool

Why would you bother insulate a warm loft.

Better cutting it witha box cutter knife you dont get as much dust

Excellent advice, brilliant video

Great video a lot better than others I’ve seen on RU-vid

Fantastic thanks Nick!

Hey mate T Thank you for sharing the video and the tips for the 50mm installation. We received a quote of 6,000 pounds for the loft wall and ceiling, which we find too expensive. We've decided to follow your approach and make it a spring project for me and my girlfriend. We have already installed a raised floor in the loft. In your video, I noticed that you have an opening. Did you need to obtain planning permission for this? I believe adding windows to the back of the house typically doesn't require permission, but I wanted to confirm.

Great job

Super useful... Thanks

Do you need to leave 50 mm gap? What if you leave no gap, there won’t be any air and no condensation?

Nice job.

Top notch 👏😎

nice work.

No tape ?

Great finish

👍👍👍

Very useful video. Cheers mate. I bought a house with a loft conversion last year and during the first winter investigated why the living space was getting a bit cold in certain spots. Turned out that the living are is insulated with 100mm PIR, but the rafters in the eaves area aren't. There are also holes in the felt, which apparently are meant for air circulation via the cowl vents but I think they might be a little OTT, given that the bottom of the rafters have access to outside air anyway. I'm thinking of putting additional 100mm PIR in the rafters now. I can see that you have not installed cowl vents and just rely on the 50mm between the PIR and the felt, is that correct? thanks!

Really great that you mention the PPE and even the ear defenders. Health is wealth at the end of the day and it's not worth having a brilliantly insulated loft that you can't get up to cos you've done your lungs in during the build. Also, nice to see you've gone with the rigid insulation from the wall plate to the ridge. Great work!

If we haven’t left an air gap behind a 100mm KS board what can we do? This is in a garage, and there is no loft, just very high ceilings to the rafters

And because you used foil backed boards you have now made that house a faraday cage. Good luck with phone signal. Wi-Fi will be ok thou.