How to insulate over rafters. Over boarding insulation. Cut and fit PIR board DIY beginners guide!!

Рет қаралды 97,524

2 жыл бұрын

In this video I show you a step by step guide of how to overboard (rafters with insulation (PIR) board. I show how to measure, cut, fix, foam and tape the boards and show you the tools and products I use to carry out this task.
For the tools used in this video click here:
Makita LXT 18V Impact Driver & Drill plus batteries (Twin pack)- amzn.to/2txC1Rn
Makita LXT 18v 5Ah Li-ion batteries - amzn.to/3mAMMbU
Hand saw - amzn.to/38QudtA
Stanley knife twin pack - amzn.to/37gkfSh
Stanley spirit level - amzn.to/37jCbMX
Pencils - amzn.to/32BclRk
Stanley 8m measuring tape - amzn.to/37XWzBu
Draper 9 piece hole saw kit - amzn.to/2GVU5ry
Expanding foam gun - amzn.to/3ifW5xX
For the products used in this video click here:
30mm insulation board - amzn.to/31L5bKb
M6 penny washer - amzn.to/3aVaBY0
50mm drywall screw - amzn.to/3pm0zYi
Face Mask - amzn.to/3nIsZaO
Expanding foam - amzn.to/3kNSAk2
Aluminium tape - amzn.to/3ibTNji
For other insulation tutorials click here:
How to Cut & fit insulation between rafters - • How to cut & fit insul...
How to cut thin insulation board - • How to cut thin insula...
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Thanks for watching!
#fitPIRboard #insulationboardhowto #overboardinsultion #cutandfitPIRboard

Пікірлер: 100

@DavidLee-cw6ci 2 жыл бұрын

Oh my god that sound when you're cutting the board! I think I just broke my toes curling them so hard!

@POUSEaroundtheHOUSE 2 жыл бұрын

I'm the same touching polystyrene! I guess insulating lofts isn't for you then?! Thanks for watching. 👍

@oliviafandes5155 Жыл бұрын

Very good exploration, excellent,.👏👏

@samspencer7765 Жыл бұрын

You're a really good communicator, the detail you put as to why you choose certain things over others makes so much sense.

@Oriellastraseporcelanataria 2 жыл бұрын

Muito bom parabéns

@HandySam 2 жыл бұрын

Where was this video last week when i needed it !? 😂 Thanks for the video!

@POUSEaroundtheHOUSE 2 жыл бұрын

Sorry! Thanks for watching 👍

@DanA-fk6tl 8 ай бұрын

Great video. Clear and concise. For cutting PIR and trimming dried foam. I prefer a bread knife to a saw. No dust from the PIR and lighter and easier to to get into tight spaces for trimming the foam. Breadknife goes straight back in the drawer when you're done.

@POUSEaroundtheHOUSE 8 ай бұрын

Thanks for the feedback.

@UFZ7482 10 ай бұрын

What I do is place the hole cutter in the first hole with the bit pointing out, then offer up the next layer of insulation, and press, the centre bit makes a hole in the outer layer, this then the centre of the new outer hole.

@normanboyes4983 2 жыл бұрын

I cut mine with a TS55 Tracksaw mm perfect and did not need any expanding foam.😉 Good vid.😀👍

@POUSEaroundtheHOUSE 2 жыл бұрын

Thanks for the tip and thanks for watching 👍

@AbdulKadir-fz4pq Жыл бұрын

Hi mate thanks for the video very helpful, have my made a video putting the ceiling plasterboard on

@POUSEaroundtheHOUSE Жыл бұрын

I haven't yet but there will be one as part of the loft conversion series on my channel. Hope that helps. Thanks for watching.

@aarongallimore 2 жыл бұрын

Thanks for this video, very helpful. I have a garden room I'm about to do this in... I also have two cheeks that are deeper than the rafters, I quite like the idea of leaving them proud of the plasterboard and skim, is that what you did here?

@orielfranco9181 2 жыл бұрын

👏🏼👏🏼👏🏼👏🏼

@bigjman50 Жыл бұрын

Hi Do you use any recessed light housing in the foam board when installing your lights? Thanks!

@millin2222 6 ай бұрын

Thanks great video. What thickness of insulation boards would you suggest for insulating in between the rafters in a loft, cheers and thank you

@over-engineered 8 ай бұрын

Tip, use ‘insulation foam’ instead of ‘gap filling’ expanding foam if you don’t want too much expansion.

@askmisspatience 2 жыл бұрын

I use an oscillating saw with spray foam. The flat blade tip works with a clean cut. I make sure to have help of an edger (board or flat surfaces tool) to guide so as not to cut into the insulation. This is a really helpful video. Thank for the demonstration

@POUSEaroundtheHOUSE Жыл бұрын

Sounds like you have a good plan in place. Thanks for the feedback 👍

@DanA-fk6tl 8 ай бұрын

Breadknife works really well too.

@askmisspatience 8 ай бұрын

@@DanA-fk6tl I’ve seen the electric one’s my grandma used back in the 70’s like a sawsal. They’re amazing

@pndthaker Жыл бұрын

Question: The underside of my roof is just wood - no lining. should I stick/staple some form of lining before covering it with the foamboard? If I put in foamboard insulation between the rafters, is it necessary to cover that with 10-20mm foamboard over the rafters? How do I introduce ventilation?

@BreakBeatStu 10 ай бұрын

Question - with a loft insulated with pir board like this could you still and a traditional layer of knauf or rockwool roll installation on the ceiling (loft floor)? Am just asking as I have a new build with this type of loft insulation and I am thinking what I can do to increase my insulation. Not a loft conversion in my case, just a small normal loft space on a 2.5 story house.

@waqargul3321 7 ай бұрын

WELL DONE mate keep it up man 🇵🇰🇬🇧❤️

@POUSEaroundtheHOUSE 7 ай бұрын

Thank you 👍

@christophermackin147 Ай бұрын

You need an oscilating tool. Save you a lot of time on the cuts and foam cleanup. Good work!

@KennyEvansUK Жыл бұрын

Those windows have issues. Ideally you need a 90 degree right angle slope at the top and bottom to allow free movement of air. Having that 45 degree stop at the top is a recipe for condensation formation and the same at the bottom interrupts the flow of air and can cause the same at the bottom as it eddies around that edge. Both Velux and Keylite make a big point of this in the install instructions. Since June 2022 you need about double that amount of insulation to get the required u-0.15 value on the pitch.

@sidorgeorge 10 ай бұрын

Our Velux skylights are installed exactly the same way, at a 45 degree angle, and have been for years. We've never had any condensation issues. How would you even get a 90 degree angle in there? It would look really odd.

@moneysavingtips7006 2 жыл бұрын

Hi, thanks for your videos there really helpful. I start my loft conversion during covid and try to work on it at least 1 day of the weekend. Im at a stage now were ive fitted 50mm insulation inbetween rafters and have used the foil tape and expanding foam, as you instructed. My question is do i need to pit on a further 10mm insulation boards across all raftors covering everything or is it to pit plaster boards on instead. Keep up the good work.

@POUSEaroundtheHOUSE 2 жыл бұрын

I take it your conversion isn't being done to building regulation standard? They would request 100mm between rafters and 30mm underneath in all habital parts of the conversion. Then plasterboard over that. If its just a temporary storage space (not to building regulations standard) then I guess you can do what you like as long as you are mindful of good ventilation. Obviously the thicker the insulation the warmer the room will be. Hope that helps.

@moneysavingtips7006 2 жыл бұрын

@@POUSEaroundtheHOUSE Hi , thanks for your reply. It will be used as a spare storage/ room. Inbetween the rafters i only have a capacity of 70mm depth and and 330mm width hence why i choose 50mm insulation to fit. Im not to sure what build regs are in Manchester but will investigate. Ill fit a sheet of 30mmover it and then plaster as you suggest. Thanks for the reply and keep up the good work. 😉

@POUSEaroundtheHOUSE 2 жыл бұрын

@@moneysavingtips7006 if its just storage you could go 20mm or 25mm insulation which is a touch cheaper and readily available. Best of luck.

@lashondagordon915 6 ай бұрын

Could i cover the insulation with sheet rock or a wooden ceiling?

@donalddavies649 12 күн бұрын

Is there any repeated thermal bridge concerns using metal fittings? Are there plastic cap versions to mitigate that issue?

@timwyld573 Жыл бұрын

Don't worry if you only have a fairly new sharp saw. That will work too! Perhaps even better. :)

@soldbywinakey706 2 жыл бұрын

I Highly recommend scoring ng with a utility knife on the foam board. Then just snap it off, just like drywall. Faster and MUCH cleaner

@POUSEaroundtheHOUSE 2 жыл бұрын

I did show that at 3mins 20 secs in the video. I have another video on how to do exactly that. Thanks for watching. 👍

@philipalexander79 2 жыл бұрын

Hi Pouse, or anybody else reading this! Can i just attach the insulation boards straight onto the rafters? And not bother fitting the board in-between? (I'm keeping it as a loft and just want better insulation for the house). Many thanks

@POUSEaroundtheHOUSE 2 жыл бұрын

Yes of course that's fine. Wouldn't meet building regs for a conversion but it will provide some extra insulation and maintain an air gap between your rafters. Worth checking you have some airflow at the eves. In my installation I used fascia vents. Best of luck.

@donaldmcintosh6940 2 жыл бұрын

Nice vid👍Do you need to add a vapour barrier to this before the plasterboard?

@gumboe2007 2 жыл бұрын

I wondered the same

@POUSEaroundtheHOUSE 2 жыл бұрын

I wasn't required to as I have a vented air gap above the insulation with facia vents at the eves, and a breathable membrane above that under the slates. So if ant moisture were to seep through the insulation its simply vented away from the roof space. However the insulation is double foil backed, gaps filled and taped so it will act as a pretty good vapour barrier in its own right. That said, it's worth checking with your building control officer as they will tell you the most recent best practice. Hope that helps.

@veekay9045 7 ай бұрын

Thanks for the video, very helpful. I have a question wondering if you can help? I am looking to replace mineral wool loft insulation with sheet insulation in the roof. I dont want to convert it to a room due to low height, but would like to board certain areas for storage. Is sheet insulation sufficient in the roof or do i need to also do mineral wool under the boarding? Sheets are expensive but i hate the wool gathering dust overtime. Thank you

@POUSEaroundtheHOUSE 7 ай бұрын

Yes you should use sheet insulation in the roof (between rafters? But you need a gap above rafters ideally 50mm between insulation and roof felt / membrane. Then you need to add soffit or fascia vents to allow air in to circulate. If you watch my loft conversion vids and 'insulate between rafters' vid that may help. Best of luck, thanks for watching 👍

@sean550 4 ай бұрын

Have you to.put insulated baord over the ones in between rafters ...if you putting plasterboard over it isn't it double insulation..do you mark it to find the rafters for plaster board.

@trustnobody123 Жыл бұрын

I have a studded plasterboard wall with standard loft insulation strapped to the back of it which is rubbish amount of insulation.. There is a void behind the stud which goes 4 feet backwards to the angled roofline. What is better... Celotex 50mm screwed over the top of the old mineral insulation behind the plasterboard or go 4 feet to the rafters and place pir board there between each rafter. If so do I leave the old mineral insulation where it is? Nobody can give me an answer. Not even building control.

@brianwitton5061 11 ай бұрын

Do I need to overboard with insulation if I’m not plastering.

@onionthemillionairetrader7405 2 жыл бұрын

Hey Pouse, when will part 34 of the loft conversion series be coming out?

@POUSEaroundtheHOUSE 2 жыл бұрын

Soon hopefully. Just need to edit a few and get them uploaded. Thanks for watching 👍

@1979com 6 ай бұрын

i was wandering, can i do the same method on the downstair floor in a uk house? and has anyone done that? thanks

@huckmulligan1609 3 күн бұрын

How is the plaster board installed after this? Long screws?

@tomshorrock1589 Жыл бұрын

Just wondering why you're putting insulation board over the insulation that's already there between the rafters? Can you not put plaster board directly over insulation that's in the rafters? Thanks

@joshbarnett9559 8 ай бұрын

Hi, how do you now attach the plasterboard? I have a Victorian house and am looking to remove the ceiling at the back of the 1st floor where the half pitched roof doesn’t have much space above it. In order to insulate the roof battens, can I just overboard with the second layer of insulation without having to extend the depth of the battens?

@POUSEaroundtheHOUSE 8 ай бұрын

Here's a video of me olasterboarding my loft conversion. Hopefully it helps. I insulated between rafters, and then over the top - kzfaq.info/get/bejne/eahmidGi0JrKe6s.htmlsi=sXDyGLQ5bYDe8QiB

@joshbarnett9559 8 ай бұрын

@@POUSEaroundtheHOUSE thanks mate. Do I need to worry about the extra weight being added to the rafters? Property is 1900 terrace and rafters are only 70mm deep so I would need to put 20mm between them, then at least 100 over before boarding and skimming.

@davidbanner9001 2 жыл бұрын

When you installed the PIR in this video were you also making where the rafters are? So that you know where the centers are for the plasterboard screws?

@POUSEaroundtheHOUSE 2 жыл бұрын

Yes, probably should have mentioned that in the video. I mark top of rafter on ridgeboard, bottom on purlin, then once covered, use a straight edge to mark a line along centre of the rafter. Thanks for pointing this out 👍

@keithkennedy2409 2 жыл бұрын

Hi loved the video I’m just wondering also could you have just used a 30 mill insulated plaster board under neath the rafters in stead of just a 30 mill insulated board this would have stopped you then putting up plaster boards again ? Less time consuming Great video love to hear could you have done this thanks in advance can’t wait to see the plaster boards been fitted next

@mikebuick2332 2 жыл бұрын

Pouse, totally unrelated question. Whatever happened to the elephant rescue plan? Just started watching all of the loft conversion videos and now I’m hooked. Hopefully my bungalow won’t be a pile of rubble within a month!

@POUSEaroundtheHOUSE 2 жыл бұрын

The Elephant Rescue Plan just 'stopped'. Gig fatigue! Best of luck with the bungalow, let me know how you get on with the renovations.

@mikebuick2332 2 жыл бұрын

@@POUSEaroundtheHOUSE Cheers Pouse 👍

@patrickmansfield5604 Жыл бұрын

Hi, I noticed you didn't add a vapour barrier after fitting the PIR boards. Is it not necessary for such a job? I'm planning to fix some form of insulation under the rafters in my loft space like this. Thanks.

@g4egk Жыл бұрын

Depending who you ask, the foil on the PIR + tape can act as a vapour barrier. Others will say you need a more continuous membrane. Some videos say don't use expanding foam around the edges, use Gapotape instead.

@tgb4921 8 ай бұрын

i need to insulate an outbuilding - I’m installing 100mm insulation board between rafters and on top of that I’m just going to install plasterboards. Do you think i need these thinner insulation board installed before I put plaster board?

@POUSEaroundtheHOUSE 8 ай бұрын

The reason for the thin sheets is to avoid thermal bridging through the timber and is required under building regs on a loft conversion. There is no requirement to do it on an out building and 100mm will be warm anyway. So I guess it's up to you. You can buy plasterboard with 25mm insulation attached to it save attaching twice. Hope that helps, best of luck 👍

@neilshotter4250 Жыл бұрын

WHEN PUTTING IN THE INSULATING BOARDS DO I PUSH IT WRITE DOWN TO THE CAVITY WAS AND WRITE TO THE TOP ( RIDGE ) OR DO YOU LEAVE A GAP ?

@Kjwcube135 Жыл бұрын

You need to leave an air gap along the back of the insulation the length of the pitch. Looks like you go as long as you can, from top of the cavity to bottom of ridge. Have a look at the previous video as well for more information: kzfaq.info/get/bejne/j853osiDmbeYpIE.html

@paulwilliams6827 Жыл бұрын

Hi mate do you do work locally in Swansea looking for some velux to be installed

@POUSEaroundtheHOUSE Жыл бұрын

It's just DIY, I don't work for other people sorry. Good luck in your search! Alternatively you could watch my velux install video and try yourself, link here - kzfaq.info/get/bejne/jZqlns2bvp-sfp8.html. Thanks for watching 👍

@paulb9245 8 ай бұрын

Hi mate did you get anyone to install your velux windows, I live in swansea and have recently installed four into a vaulted ceiling and am happy to provide some advice.

@paulwilliams6827 8 ай бұрын

@@paulb9245 hi appreciate the reply been let down by a roofer just waiting for a builder to get back to me, I woukd do it myself apart from the tiles battening and cutting into fabric at top for the rain off fitting, but thanks 👍🏽😊

@theoneandonlymattp 8 ай бұрын

After seeing you video on rewiring your garage, i'm quite invested in watching most of what you're doing now. One thing i would suggest though, is the facemask you are using is not sufficient as you have a beard there is no adequate seal to prevent dust ingressing between the seal and your face.

@POUSEaroundtheHOUSE 7 ай бұрын

Thank you for the sound advice 👍

@theoneandonlymattp 7 ай бұрын

@@POUSEaroundtheHOUSE No Thank you, your video really helped me. I Managed to get my garage sorted now, just need to finish putting in points for external security downlights, and like you find someone to inspect it and sign it off.

@denishanna 2 жыл бұрын

Hi buddy, I have been doing a DIY loft conversion myself and just about to start the installation. Been watching every one of your videos and they are greatly appreciated. I have one question I maybe should have asked on the last video.. I need to leave a 50mm gap behind the rafters , I noticed you have insulated right up tight the the ridge board . As the 50 mm gap is for airflow should that gap also be left under the ridge to allow that air flow to both sides of the pitched roof. I'm trying to decide if I should drop the ceiling down to allow 50mm gap under the ridge /between the ridge and insulation to allow air to flow continuously around the full roof eg. Air comes in from the front of the house and exits the back. I hope I've explained this enough and make sense . I would love to hear your opinion on this. Keep up the videos I've got some knowledge from everyone of them

@POUSEaroundtheHOUSE 2 жыл бұрын

I replaced the all the old bitumen felt with a new breathable membrane when I reslated the roof so this combined with my air gap and fascia vents was acceptable. But one possibility is to drill some holes along the length of your ridge board within 50mm from the tip of the ridge board which will allow flow across the ridge. Just make sure it does impair the structural integrity of the ridge board. Hope that helps and best of luck with it. 👍

@frankbrooker6569 8 ай бұрын

Wont it sweat between the sheets ? Im currently doing similar but told to additional vapour barrier between

@bapoo 4 ай бұрын

What you’re talking about is interstitial condensation and it is a good question. Firstly, taping the joins removes much of the vapour passage, but not all. If overboarding with 25mm pir with sufficient insulation 5 inches or more for between the rafters above and the area below is a lived in space so stays at room temperature, it’s unlikely any rising vapour will condense until it gets further out towards the exterior part of your 5”+ pir that are between those rafters. The “sweating” or condensation will occur when the vapour hits a point that is cold enough to cause it to turn back into a liquid. This is what is called the “dew point”. There are lots of consideration factors to work out exactly where the dew point will be but generally in the UK it is accepted that 25mm overboarding won’t in itself cause interstitial in a normal lining arrangement. Vapour barrier not a bad thing but given everything else is done properly, it’s not necessary unless you have a bathroom or kitchen in the room directly below or something else that is exceptional.

@kenleague8783 Ай бұрын

But how do you put the plaster board over the insulation with no studs to nail to?

@steviepee8624 2 жыл бұрын

Is there a trick to get the boards into the loft....without taking the roof off

@POUSEaroundtheHOUSE 2 жыл бұрын

If you watch my loft conversion vids you'll see I brought them in through the window opening before split it into 2 windows. I guess you have to go for smaller boards or cut them down to a size that fits through your loft hatch. Hope that helps. Thanks for watching. 👍

@soulrider678 Жыл бұрын

This and the previous have been really helpful. Have to install 100mm insulation in the pitched roof so confident I can do that however rather than 40mm on top of the rafters I have to use the 52.5mm kingspan insulation backed plasterboards and I get the feeling that won’t be easy to do. You done a video with the plasterboards on yours at all?

@POUSEaroundtheHOUSE Жыл бұрын

I'm currently editing a loft conversion video where I fit the plasterboard over the insulation. I just used long drywall screws and screwed it over the top of the insulation so same principle just in two stages whereas yours is one stage as it's stuck together. Best of luck with it 👍

@soulrider678 Жыл бұрын

@@POUSEaroundtheHOUSE Cheers, will keep an eye out for that video as well

@jericho9653 3 ай бұрын

What about spraying the rafters with a breathabke foam and a 2 inch ventilation card

@vicecitylover 21 күн бұрын

I dont think there is such a thing as breathable foam...

@storiesforniamh.. 8 ай бұрын

Does it not act as a bridge for water on the underside of the felt?

@POUSEaroundtheHOUSE 8 ай бұрын

You need to leave a 50mm gap between insulation and felt and then use tge correct size fascia vents or soffit vents to allow airflow along that gap right the way to the ridge. Hope that helps.

@coolramone 2 ай бұрын

So that is 1 inch and 2 inch foam board that you are putting between and over the rafters.

@philipgardner-uz5ne 7 ай бұрын

Did I miss,a vapour barrier?

@POUSEaroundtheHOUSE 7 ай бұрын

My foil pir board insulation sealed with aluminium tape act like a vapour barrier. But as it is vented above the insulation there is no need to add a vapour sheet vapour barrier. I have used fascia vents and left an air gap between the insulation and breathable membrane under the slates as specified by building control. Hope that helps.

@nasko4884 5 ай бұрын

How much is 50mm insulation

@POUSEaroundtheHOUSE 5 ай бұрын

Completely depends on where you buy it from and when!

@marcinlasota80 5 ай бұрын

What kind of builders you are where you wearing slippers 😅

@g.wes.3906 Ай бұрын

The best kind. Slippers show a higher level of skill.

@garethwilliams2160 2 жыл бұрын

🙈🙈🙈🙈🙈 fixing the insulation boards prior to plaster boarding is 100% pointless, cut them so they are snug and board over them, easier and quicker job, making work for no reason there mate 👍

@POUSEaroundtheHOUSE 2 жыл бұрын

They'll just fall down. And this way it means you get your insulation fitting snug and correctly with no air gaps. Impossible to do it together and not have gaps in insulation. Problem is when people work on other peoples house they don't care, but when it's your own house, you soon find out if someone has rushed the job when you have cold spots and condensation in you roof. Thanks for watching.