Really good video and a good idea using the circular saw for the initial cut. You don't appreciate how hard it is to work with until you start using PIR (especially 100mm+) I've recently insulated our subfloor in our 100+ year old cottage which had a cellar underneath. Was an absolute nightmare to do. It's made a great improvement already 👍
Couldn't agree more about circular sawing. I did my garage roof recently and decided to try using my 18v saw as the blade was pretty knackered anyway and it worked a treat. So much better than hand sawing.
I have been using a plunge saw like this for a while, I use a bit of straight batten with 2 nails in it, measure 32mm longer than I need, (that is the distance from the edge of my skill saw metal base to the blade) and put the wood on this line, the nails hold it in place and you have a straight guide to run your saw along. Then hand saw to finish. It will be as straight as the wood you have and as accurate as your tape measure.
I put a sheet of plywood on two sturdy saw horses, and have the cut line over the edge of the plywood. Once marked up, I stand on the PIR board, and use a regular jobsite saw. After the saw is fully through the start of the cut, I use a set of single handed clamps to stop the piece that's being cut from sagging down and snapping as I others through the cut. The trick with standing on the workpiece is that I have no trouble eyeing a plum cut as I go along. Hold onto the piece after the cut is complete, and carefully set it to ground. Hoover both cut faces to minimise them mess getting everywhere.
Honestly after using gapotape and spray foam to fit pir between rafters I'm convinced the way to go is to use high performance glass mineral wool (0.032W/mK) and only use pir below the rafters, especially when their not particularly straight, there's either a huge performance gap or it takes a short age to do
Are we not supposed too have 1 third insulation in stud and 2 thrids on the cold side , thus eliminates cold bridgeing then tape up ,vapour barrier and batton and counter batton for services , but ye trussed roof new ones, good point
I have just done this job in a vaulted ceiling, the timbers twist and are often not parallel so just cutting and fitting is not likely to be good enough in my opinion. I bought a Festool saw which I will sell when the project is finished, they hold their value well. I also decided to use Gapotape which is a great product and worked really well for my project but it does cost a fair bit more.
I have a single redbrick garage, no Insulation. I'm looking to insulate the walls with 72.mm Kingspan and use gyproc that already has the isulation. Can i use batten on the uneven brick walls to somehow level walls, then attach the kingspan? What is the procedure for concrete floors as this is what i currently have. Would i completly make the existing floor level with leveling cement?
South African houses are generally only insulated in the ceiling (mostly against heat), so to me at least, the only PIR we know of is "passive infra-red"...as in motion detection.
Expensive cars? I’m going to be insulating my garage eventually as the humidity inside is off the scale. Don’t want my cars and anything steel to rust.
Expensive cars? Heated and humidity controlled would be my guess. Or they have something like a lathe or dimmer other such workshop tools in there and don’t want them rusty and want to be able to work in there.
So have they put planning permission in / building regs for a garage Then once totally finished and signed off They remove the garage door and fit bi folding doors ????
That is a lot of holes in your membrane when you fix your cladding. Alternative method: use PIR 25mm less than your studs (eg 100mm studs = 75mm PIR). Fit PIR, staple membrane to studs, wrap battens in butyl rubber to protect them from moisture and to seal fixing nails, then fix battens over membrane into studs which secures the membrane, fix cladding.
It's expensive because Kingspan endorses politicians who create regulations that basically make it illegal not to use it. With leverage like that, they can charge what they like.
It's much like PUR foam except they need to have it expand consistently, coat it and deal with the cyanides that escape. Also brands can be quite different. My prefered supplier has a 44 mm Kingspan at € 16,39 each, while a 50 mm (better insulation) from Iko Enertherm that's identical in every way, costs € 14,85 each. Another supplier has identical 100 mm PIR Kingspan: € 20,64, Unilin € 18,14, Idelco € 17,41
The note in the building regs now says that all unavoidable gaps must be filled with compressible tape. No brand is specified and if you don't have any gaps you don't need the tape. I suppose that it depends what you call a gap. The way Sam and Jen have done it here avoids the gaps. This building isn't being inspected but it is a good demonstration of how to do the job properly.
Gapotape is not required mine passed recently without. Just ensure you have no gaps. I fitted 150mm between rafters and 30mm kingspan cooltherm over, inspector hardly looked.
It's just the best fun fitting PIR into renovations. 90 year old sagged rafters, at random centres, twisted, curved, and never parallel. Have a box of foam and plenty foil tape on hand. 🫠
It’s a joke. Should be banned for the inbeetweens. Actis multifoil should be permitted. It may not have the same u value but when not fitted in factory conditions you won’t achieve it with our board anyway
Take a measure top and bottom and add an extra 4/5 mm, force it in and use a panel saw down the side of a rafter to sort of "scribe it in" foam and foil tape to fix the imperfections. There really is no other way to do it in an old house, this tutorial only looks so easy because everything is new and built with modern technology. I also find that a jigsaw with a fine blade cuts far cleaner than a circular saw which tends to just blow billions of dust particles in the air. Horrible job either way, I avoid it like the plague now.
@russzippo9640 haven't had a go with the multi foil yet. Why not treat it like replacing an old stair, where you're permitted to improve but practicality means you might not meet current regs. PIR isn't practical either if you blow the labour budget on install. Bonkers economy!
@mlawlan69 foil tape doesn't insulate tho. Just covers. Better to use a soft insulation between these irregular timbers. Or spray foam if that adds up (it may not be appropriate or cost- effective).
@SkillBuilder We fit them a lot and always a very tight fit. Like to tape the edges and joints which only touches the foil, but very reluctant to trust a sealer won't have a reaction with the insulation itself .I guess time will tell
i used to work in a timber frame factory, we would use the table saw for cutting insulation but it was a big blade on the table saw so could get away with it. if there was a lot of pannels or flooring cassettes needing insulation, someone would get the batch job to cut them all and write the sizes on them so just pick it and place it, hand saw it to get it to fit and reflective tape (like whats on the insulation board) to cover up and seal the joints. just a pain in the arse that so much dust comes from all the insulation that it requires a mask.
I used alligator saw with a ground down 8" blade - used bench grinder to remove teeth, and chamfer edges to make a blade like a bread knife. This cuts with barely any dust. I believe purpose- made blades can be bought, I didn't know this back then (2019). The Bahco hand saw for insulation is the perfect profile, but slower. Obvs. Was advised not to try to get perfect fit, but deliberately leave gap and foam all round. Gapotape arrived on market just as job finished.
450 centres won't give you 355 between, guess you meant 400 centres! using a circular saw is by far the best way i think, its much quicker than even using the festool insulation saw, with the deep PIR, do a cut both sides and the insulation literally snaps for a perfect cut, have to do tons of this stuff in the loft conversion we do 👍
The Festool saw is far quicker, I made a parallel guide for mine that attaches to a guide rail which makes it even quicker as there's no need to mark the PIR.
A jigsaw with a 150/170 blade and a half sheet of ply made into an offset square will do a far superior job with less dust , yes the blade will wander if you overuse it or force it but if your steady one blade would do that “garage-lol” . Also building paper and then c/ battens would remove the need for vent strip/ mesh . Just saying .
Soft blade from bosch on a jigsaw leaves no mess or dust. This is by far the easiest and cleanest way to cut insulation sheets or foam. The way you're doing this creates so much mess.
Cut insulation ever so slightly bigger. Place a flat off cut of wood against the insulation and hammer the wood so it forces the insulation in snug but does not damage it. Harder work but zero gaps. Also should use insulation tape. Mastic will stop air but probably zero thermal efficiency. Tape has reflective layer and may reflect infrared radiation.
Another pro tip: Always cut the panels somewhere inside and vacuum directly after cutting. The sawdust of the PIR insulation, espacially when cutting by hand, is a forever chemical and microplastic. I.e.: extremely bad for the environment.
The dust is absolutely horrible, and off it goes, into the enviroment. I'm not just having a go at this job, it happens all the time. I think PIR is a disgusting product, but unfortunately it's the best insulation we have for many situations. No doubt there will be an expensive scheme to remove and dispose of it in the future, creating a whole new industry. "It's ok if you don't have to disturb it, but if you need to drill or cut through a wall containing PIR, get the professionals in," I can hear it now. I have also known the dust to cause a circular saw to pack up, by the way.
What will people do in 50 year's time, when it's turning to dust inside a block cavity wall? Only corruption could make such toxic stuff the material of choice in "eco-friendly" homes.
Why apply sealant round the edges if you are then going to cover that with aluminium tape? Either trust the sealant or trust the tape; using both is wasteful of time, money and resources.
Kingspan ( and the other brands) are real ecological products, safe to install in the family home.. Also there is no risk of killer fumes to the occupants in the case of fire.... A public announcement on behalf of the rigid foam insulation association..
Grenfell inquiry: polyisocyanurate (PIR) and phenolic foam insulation boards behind the ACM “contributed to the rate and extent of vertical flame spread”; components of the window surrounds, manufactured by Celotex and Kingspan, were also thought to have aided the spread of fire. building co uk/ focus/grenfell-inquiry-explainer-how-rival-insulation-firms-covered-up-fire-safety-data/5109471.article
Grenfell inquiry: polyisocyanurate (PIR) and phenolic foam insulation boards behind the ACM “contributed to the rate and extent of vertical flame spread”; components of the window surrounds, manufactured by Celotex and Kingspan, were also thought to have aided the spread of fire. building co uk focus grenfell-inquiry-explainer-how-rival-insulation-firms-covered-up-fire-safety-data/5109471.article
Err. What are you insulating a garage with insulation made from petro-chemicals for. This is as close to insanity as I have yet seen in building. Oh! is this to bring down engine warm up times...... now it all makes sense.
It always amazes me how many people don't understand how the building trade works. Customer I am having a garage built and I would like it insulated. Builder Why are you insulating your garage? Customer If I told you that I would have to kill you. Builder Fair enough, what you do with your private life is your business.
Really good video and a good idea using the circular saw for the initial cut. You don't appreciate how hard it is to work with until you start using PIR (especially 100mm+)
I've recently insulated our subfloor in our 100+ year old cottage which had a cellar underneath. Was an absolute nightmare to do. It's made a great improvement already 👍
Rubbish. No Building Control operative will want to see thermal images. Just do your best and follow the rules
Buying the festool insulation saw was game changer
Couldn't agree more about circular sawing. I did my garage roof recently and decided to try using my 18v saw as the blade was pretty knackered anyway and it worked a treat. So much better than hand sawing.
Over the years I've tried just about every method out there but still think this is best for me!
I have been using a plunge saw like this for a while, I use a bit of straight batten with 2 nails in it, measure 32mm longer than I need, (that is the distance from the edge of my skill saw metal base to the blade) and put the wood on this line, the nails hold it in place and you have a straight guide to run your saw along. Then hand saw to finish. It will be as straight as the wood you have and as accurate as your tape measure.
That's some shed! Better built than my house
I put a sheet of plywood on two sturdy saw horses, and have the cut line over the edge of the plywood. Once marked up, I stand on the PIR board, and use a regular jobsite saw. After the saw is fully through the start of the cut, I use a set of single handed clamps to stop the piece that's being cut from sagging down and snapping as I others through the cut. The trick with standing on the workpiece is that I have no trouble eyeing a plum cut as I go along. Hold onto the piece after the cut is complete, and carefully set it to ground. Hoover both cut faces to minimise them mess getting everywhere.
Gapotape anyone? All this precision is a fantasy when doing attic trusses with the flex in the timber.
Gapotape all the way
Honestly after using gapotape and spray foam to fit pir between rafters I'm convinced the way to go is to use high performance glass mineral wool (0.032W/mK) and only use pir below the rafters, especially when their not particularly straight, there's either a huge performance gap or it takes a short age to do
Are we not supposed too have 1 third insulation in stud and 2 thrids on the cold side , thus eliminates cold bridgeing then tape up ,vapour barrier and batton and counter batton for services , but ye trussed roof new ones, good point
@@leonsletterbox2013 Sounds a proper job, would love to have done that my self.
All well and good when it’s an easy job try doing one where the timber work is all over!
That's a beautiful garden building.
You can use a track saw. If you are accurate you can turn the sheet over and do 120mm. The tracks away can also do bevels.
That superb build would not have been possible without Kingspan Therma. Thank you Kingspan - you're the best. wink
😂
This message is sponsored by Schnappes
Nice to see Sam has his Daughter teaching him what to do.
Wife!
@@SJWardBuilders yeah I know, was trying to be a lame joke. I noticed you didn't correct the comment about her teaching you 😜
Apologies if I offended anyone
@@jockwalker24 😀
@@SJWardBuilders
Oh wow that went from zero to Alabama in a second. 😉
I wonder if vapour barrier is needed on the warmer side. You give me an example, no need to .
If you've a table saw. (obviously with dust extraction) Try that. It makes the whole process almost enjoyable.
😂
I have just done this job in a vaulted ceiling, the timbers twist and are often not parallel so just cutting and fitting is not likely to be good enough in my opinion. I bought a Festool saw which I will sell when the project is finished, they hold their value well. I also decided to use Gapotape which is a great product and worked really well for my project but it does cost a fair bit more.
That car will be warmer than I will be this winter........
Nicely fitted team Ward. 👊🏻
Thanks Dan!
Nice to have PPE but what protects the surrounding nature from breathing in plastic particles ?
That's a good question maybe Roger has the answer!?????
Yeah, all those little plastic particles blowing around FOREVER!
A nice bit of ad-hoc Air b n B accommodation. And no planning or building regs needed😂
Bosch do a blade for cutting PIR that fits to a jigsaw. Looks like a bread knife. It works for me
I have a single redbrick garage, no Insulation. I'm looking to insulate the walls with 72.mm Kingspan and use gyproc that already has the isulation. Can i use batten on the uneven brick walls to somehow level walls, then attach the kingspan? What is the procedure for concrete floors as this is what i currently have. Would i completly make the existing floor level with leveling cement?
South African houses are generally only insulated in the ceiling (mostly against heat), so to me at least, the only PIR we know of is "passive infra-red"...as in motion detection.
Hi Sam, can you use this approach on the exterior of a brick wall on a house?
Why are we insulating a garage with pir ???? I think there's a bifold going where the garage door is 😉
Expensive cars? I’m going to be insulating my garage eventually as the humidity inside is off the scale. Don’t want my cars and anything steel to rust.
Expensive cars? Heated and humidity controlled would be my guess. Or they have something like a lathe or dimmer other such workshop tools in there and don’t want them rusty and want to be able to work in there.
@@davideyres955insulation won’t change the humidity
😂
@@davideyres955 Now just need a garage door that is not worse than all the walls of the building...
great until you get to my house with the rafter centres all different and running out as well ha ha🤣🤣
So have they put planning permission in / building regs for a garage
Then once totally finished and signed off
They remove the garage door and fit bi folding doors ????
Interesting to see you working inside > outside.
That is a lot of holes in your membrane when you fix your cladding. Alternative method: use PIR 25mm less than your studs (eg 100mm studs = 75mm PIR). Fit PIR, staple membrane to studs, wrap battens in butyl rubber to protect them from moisture and to seal fixing nails, then fix battens over membrane into studs which secures the membrane, fix cladding.
The thing I most want to know about PIR is why is it so expensive? What materials are used to make it? What is the manufacturing process?
It's expensive because Kingspan endorses politicians who create regulations that basically make it illegal not to use it. With leverage like that, they can charge what they like.
It's much like PUR foam except they need to have it expand consistently, coat it and deal with the cyanides that escape.
Also brands can be quite different.
My prefered supplier has a 44 mm Kingspan at € 16,39 each, while a 50 mm (better insulation) from Iko Enertherm that's identical in every way, costs € 14,85 each.
Another supplier has identical 100 mm PIR
Kingspan: € 20,64, Unilin € 18,14, Idelco € 17,41
The garage have heating?
I thought gapotape or equivalent was required now in the regs?
The note in the building regs now says that all unavoidable gaps must be filled with compressible tape. No brand is specified and if you don't have any gaps you don't need the tape.
I suppose that it depends what you call a gap. The way Sam and Jen have done it here avoids the gaps. This building isn't being inspected but it is a good demonstration of how to do the job properly.
Gapotape is not required mine passed recently without. Just ensure you have no gaps. I fitted 150mm between rafters and 30mm kingspan cooltherm over, inspector hardly looked.
Hardly ever get decent inspectors anymore
We use jigsaw with insulation blade (like bread knife) hardly any mess miles quicker for me panel saw is a no go . Crap everwhere . Nice job though
I keep an actual bread knife to hand for 50mm boards
@@zassakavuma5877I use an insulation blade to cut my bread
@@zassakavuma5877 we have one hultafors do one for insulation
It's just the best fun fitting PIR into renovations. 90 year old sagged rafters, at random centres, twisted, curved, and never parallel. Have a box of foam and plenty foil tape on hand. 🫠
It’s a joke. Should be banned for the inbeetweens. Actis multifoil should be permitted. It may not have the same u value but when not fitted in factory conditions you won’t achieve it with our board anyway
Take a measure top and bottom and add an extra 4/5 mm, force it in and use a panel saw down the side of a rafter to sort of "scribe it in" foam and foil tape to fix the imperfections.
There really is no other way to do it in an old house, this tutorial only looks so easy because everything is new and built with modern technology.
I also find that a jigsaw with a fine blade cuts far cleaner than a circular saw which tends to just blow
billions of dust particles in the air.
Horrible job either way, I avoid it like the plague now.
@russzippo9640 haven't had a go with the multi foil yet. Why not treat it like replacing an old stair, where you're permitted to improve but practicality means you might not meet current regs. PIR isn't practical either if you blow the labour budget on install. Bonkers economy!
@mlawlan69 foil tape doesn't insulate tho. Just covers.
Better to use a soft insulation between these irregular timbers. Or spray foam if that adds up (it may not be appropriate or cost- effective).
@richardparsons7012 Building regs already allow this for older properties.
Will the sealer not haveca reaction with the insulation material ?
No
@SkillBuilder We fit them a lot and always a very tight fit. Like to tape the edges and joints which only touches the foil, but very reluctant to trust a sealer won't have a reaction with the insulation itself .I guess time will tell
i used to work in a timber frame factory, we would use the table saw for cutting insulation but it was a big blade on the table saw so could get away with it.
if there was a lot of pannels or flooring cassettes needing insulation, someone would get the batch job to cut them all and write the sizes on them so just pick it and place it, hand saw it to get it to fit and reflective tape (like whats on the insulation board) to cover up and seal the joints.
just a pain in the arse that so much dust comes from all the insulation that it requires a mask.
I used alligator saw with a ground down 8" blade - used bench grinder to remove teeth, and chamfer edges to make a blade like a bread knife. This cuts with barely any dust. I believe purpose- made blades can be bought, I didn't know this back then (2019). The Bahco hand saw for insulation is the perfect profile, but slower. Obvs.
Was advised not to try to get perfect fit, but deliberately leave gap and foam all round. Gapotape arrived on market just as job finished.
shame the garage door is not to the same standard but good tip with the circular saw, ty
450 centres won't give you 355 between, guess you meant 400 centres! using a circular saw is by far the best way i think, its much quicker than even using the festool insulation saw, with the deep PIR, do a cut both sides and the insulation literally snaps for a perfect cut, have to do tons of this stuff in the loft conversion we do 👍
yes you're right! I did mean 400 centres!!!!!
@@RobNorman08 353 in the clear
The Festool saw is far quicker, I made a parallel guide for mine that attaches to a guide rail which makes it even quicker as there's no need to mark the PIR.
@@Marxzy Yes agreed,!
nice job, but why insulate a garage in the first place ? there is a huge gap above garage door !
Sounds obvious, but I've seen it alot. Make sure the studs are all plumb and parallel. Then it's a simple process to fit pir.
Loads of cold bridging through the timbers should have continuous over the top
A jigsaw with a 150/170 blade and a half sheet of ply made into an offset square will do a far superior job with less dust , yes the blade will wander if you overuse it or force it but if your steady one blade would do that “garage-lol” . Also building paper and then c/ battens would remove the need for vent strip/ mesh .
Just saying .
Soft blade from bosch on a jigsaw leaves no mess or dust.
This is by far the easiest and cleanest way to cut insulation sheets or foam.
The way you're doing this creates so much mess.
Or use SF40 and save all the faf
Cut insulation ever so slightly bigger. Place a flat off cut of wood against the insulation and hammer the wood so it forces the insulation in snug but does not damage it. Harder work but zero gaps. Also should use insulation tape. Mastic will stop air but probably zero thermal efficiency. Tape has reflective layer and may reflect infrared radiation.
Another pro tip:
Always cut the panels somewhere inside and vacuum directly after cutting. The sawdust of the PIR insulation, espacially when cutting by hand, is a forever chemical and microplastic. I.e.: extremely bad for the environment.
How many builders do you know will do what you suggested get real
Every stud is a cold spot pointless getting the kingspan cut to the mm with a 47mm cold spot every 400 better of foam back boarding inside
The dust is absolutely horrible, and off it goes, into the enviroment. I'm not just having a go at this job, it happens all the time. I think PIR is a disgusting product, but unfortunately it's the best insulation we have for many situations. No doubt there will be an expensive scheme to remove and dispose of it in the future, creating a whole new industry. "It's ok if you don't have to disturb it, but if you need to drill or cut through a wall containing PIR, get the professionals in," I can hear it now. I have also known the dust to cause a circular saw to pack up, by the way.
What will people do in 50 year's time, when it's turning to dust inside a block cavity wall? Only corruption could make such toxic stuff the material of choice in "eco-friendly" homes.
and put the plastic dust in the nature !!!
Why apply sealant round the edges if you are then going to cover that with aluminium tape? Either trust the sealant or trust the tape; using both is wasteful of time, money and resources.
Kingspan ( and the other brands) are real ecological products, safe to install in the family home.. Also there is no risk of killer fumes to the occupants in the case of fire....
A public announcement on behalf of the rigid foam insulation association..
Grenfell inquiry: polyisocyanurate (PIR) and phenolic foam insulation boards behind the ACM “contributed to the rate and extent of vertical flame spread”; components of the window surrounds, manufactured by Celotex and Kingspan, were also thought to have aided the spread of fire. building co uk/ focus/grenfell-inquiry-explainer-how-rival-insulation-firms-covered-up-fire-safety-data/5109471.article
Grenfell inquiry: polyisocyanurate (PIR) and phenolic foam insulation boards behind the ACM “contributed to the rate and extent of vertical flame spread”; components of the window surrounds, manufactured by Celotex and Kingspan, were also thought to have aided the spread of fire. building co uk focus grenfell-inquiry-explainer-how-rival-insulation-firms-covered-up-fire-safety-data/5109471.article
Gapotape!!!
Building inspector 😳 give over 😂
A girl ! 😊
Is that the first one you have seen?
@@SkillBuilder 🤣
@@SkillBuilder I thought they were a myth.
What a mess around - the panel saw is literally made to cut straight. Stop using it like a jigsaw and use the full blade length.
Advert for kingspan me thinks . But nice tutorial
We are happy to have sponsorship if it helps us make tutorials.
That was a long winded way to advertise kingspan products.
First thing yer gonna need... Mask
Oh well that's me failed XD
Oh no. Rodger’s been replaced with AI. It’s the end times!
Can't you even have a 2mm gap
AI intros! Eurgh.......
Another con
Err. What are you insulating a garage with insulation made from petro-chemicals for. This is as close to insanity as I have yet seen in building. Oh! is this to bring down engine warm up times...... now it all makes sense.
It always amazes me how many people don't understand how the building trade works.
Customer
I am having a garage built and I would like it insulated.
Builder
Why are you insulating your garage?
Customer
If I told you that I would have to kill you.
Builder
Fair enough, what you do with your private life is your business.
🙄
Hooray . Nice to see Sam and Mrs Sam back on skill builder .
We use the circular saw on pir too 🙌🏽🙌🏽🧱👍🏽
Thanks Steve and Alex!! Circular saw makes a lot of dust but isn't too bad with the vac attached!
This foam insulation is toxic rubbish. Don't let it near your house.