Insulated plasterboard recommendations/advice

TheDoc

Hi all,

Starting our new project next weekend. Putting 100m insulated plasterboards (internally obvs) on all external walls in the house. Measuring out to be about 20 boards. Actually didn't have an idea on price for this beforehand and seems to be shaking out at about 1600 for the boards.

Just wondering if anyone has any thoughts/advice/recommendations in terms of boards to get, where to buy or where to avoid.

Doing it with my brother in law who knows his stuff, he just said to me to maybe checkout where the best price for them might be, as prices generally have gone a bit mad.

Sleeper12

All I can suggest is to ring a few builders providers and get prices. You won't find a massive difference between companies but you might make a small savings. I'm pretty sure I paid around €65 per 100mm board back in 2008/9.

Don't make the mistake of dot and dab. The correct way to install them is to drill 10 to 12 holes in each one and hammer in mushroom fixings

Rows Grower

If it's block wall internally you'd be well advised to use insulated slabs everywhere.

con747

Have a look at Goodwins and a few others similar. https://www.goodwins.ie/categories.html?filter_set[]=1413,1419&name=plaster%20board&type=simple

whizbang

Theres 2440 and 2400 sizes; thats not a lot of difference, but it can be make or break if one happens to be the perfect size.

Foam fix them top & bottom regardless of whatever mechanical fixing you use. Are you lifting upstairs floors and continuing below to meet the inulation below.??? If noy you might as well hang them loose from the ceiling..:)

you dont need 12 fixings.

whizbang

Also go searching now for 25mm back boxes for sockets, anytime i go looking, nobody has them.

Cut them into the foam from the back, trim the cutout piece, glue it back in, seal the edges. Then you have 35mm insulation behind the socket, and no air leak.

10-10-20

https://www.boards.ie/discussion/comment/121741779#Comment_121741779

I'm an adhesive-foam man myself. (then 6 to 8 mushroom fixings after that) 😀

In terms of cost, I think that things have stabilised a bit since 2022 where I saw differences of 15 EUR or more (on 50mm boards) between some suppliers and others. To the point that it was more worthwhile for me to hire a van (Go Car) in Sandyford and drive to Lucan to collect insulated slabs than order and deliver from the two builder's providers locally.

Here's an example: 16.83 versus 12.25.

https://www.goodwins.ie/products/soudal-genius-plasterboard-adhesive-foam-750ml-4017111.html

https://brooksonline.ie/evo-stik-plasterboard-adhesive-foam-gun-grade-750ml-uq1527

Prepare to be rode!

Sleeper12

There is a difference in installation quality between different makes of insulation board. Not all 100mm are equal. It's worth checking this before op buys.

I only mentioned dot & dab because it should never be used for insulation boards. It creates a cavity between the board and the concrete wall. This would be a breeding ground for moisture and mould.

I have never tried the foam. It would definitely be great for any gaps between boards on joins.

I have 100mm in all my rooms except box room and bathroom. I don't believe I have saved any money on heating bills but the comfort level in the house is brilliant with the insulation

TheDoc

https://www.boards.ie/discussion/comment/121741779#Comment_121741779

Yeah thats the plan, bother in law anyway said thats what he is doing anyway, mechanical fixtures all the way. Thanks :)

TheDoc

https://www.boards.ie/discussion/comment/121741850#Comment_121741850

It is yeah, but for now just going to start of with doing the external walls. We have had a few folks out to survey and the likes and the general consensus and advice was to focus and prioritise the external walls.

Doing the internal walls was discussed alright, but there seemed to be agreement it wouldn't provide much value.

Bawnmore

I was thinking of doing the same recently. We had our cavity pumped and our attic insulation sorted about 2 years ago - would we expect to see much improvement on this by adding insulated plasterboards to external walls?

TheDoc

https://www.boards.ie/discussion/comment/121743021#Comment_121743021

Yeah bro in law an electrician so he finsihed rewiring the house recently and knew this was next, so everything in place and sorted on that front :)

TheDoc

https://www.boards.ie/discussion/comment/121743674#Comment_121743674

Yeah I am not so much concerned with any money savings as just comfort.

Finished insulating and flloring out entire attic the other week, it has like 30mm of old fibreglass **** and now has mostly 200-300mm earthwool and then the flooring. The storage space has been brilliant but we've noticed a massive different in the bedrooms and my office which is great.

Sleeper12

Can i suggest you keep the receipt for the insulation boards. Possibly scan them to PC for safe keeping. If you ever get a BER cert there is a slim chance they might accept that you have 100mm insulation if you have a receipt. Without the receipts they definitely won't take the insulation into the calculations for the BER certificate. If you were selling the home a higher BER cert might get a higher resale value or possibly make a smoother sale

TheDoc

https://www.boards.ie/discussion/comment/121741896#Comment_121741896

Yeah thats the idea alright.

To be honest going to go with TJ O'Mahony. I used them for the attic insulation and boards etc. and they were grand, plus they are taking the excess insulation back and will knock the value off the new stuff I'm buying so thats that sorted really.

Will let people know how I get on

Calahonda52

https://www.boards.ie/discussion/comment/121745736#Comment_121745736

The dated invoice needs to show the number of sheets and size and the delivery address, including householders name, so cash sales just wont do

Calahonda52

IIRC there are fire regs around the fitting of these boards, I seem to recall that at least 4 per sheet need to be metal.

It may be related to the fire cert for the products.

Dot and dab or foam only won't comply

Sleeper12

https://www.boards.ie/discussion/comment/121746480#Comment_121746480

Great information 👍

jack of all

Also, just to add to the excellent advice above regarding receipts etc no harm in documenting all the work photographically.

TheDoc

Yeah I generally keep the receipts for this stuff and file away

TheDoc

We aren’t doing any dot and dab. These are being fitted with metal fixings.

starting tomorrow, everything arrived today haha

monseiur

Pay particular attention to reveals around windows & external doors to insure no cold bridging - strips of 25mm insulated slab will do the job.

Calahonda52

https://www.boards.ie/discussion/comment/121777122#Comment_121777122

with the rebate on thicker material