Loft insulation please

Mark Tomas · 17 Dec 2019

hi all, just had roof done breathable felt concrete Marley pan tile
I need to insulate now. Detached bungalow on floorboards, from what
I've read, 170mm then 100mm on top is the correct or would 170mm
Be enough....? Thanks

^woody^ · 17 Dec 2019

Mark Tomas said:
I've read, 170mm then 100mm on top is the correct

Yes if your joists are 170 deep.

Mark Tomas · 17 Dec 2019

Cheers....will need check, so if say rafters 100mm deep then its 100mm infill then 100mm
On top or 170mm....could I get away with just the infill of rafters to save costs would it
Be adequate

Mark Tomas · 17 Dec 2019

Sorry not rafters.....joists

Leofric · 17 Dec 2019

Mark Tomas said:
so if say rafters 100mm deep then its 100mm infill then 100mm

100mm between and 200mm laid other way on top, total 300mm thickness.

Mark Tomas · 25 Jan 2020

Rafters 100mm deep need 200sqm to do the job....she doesn't
Want to pay for cost of 100mm on bottom and 200mm on top
So do I just put the 100mm down or put 170 or 200 down she
Only wants 1 layer to keep costs down ?.

Ian H · 25 Jan 2020

Surely won’t add much to the cost of a full new roof.

Mottie · 25 Jan 2020

Mark Tomas said:
Only wants 1 layer to keep costs down ?.

Surely that’s a false economy? Inadequate insulation will keep the costs up. Forever.

Mark Tomas · 25 Jan 2020

£434 for 100mm and £528 for 200mm (wickes) need to cover 200sqm

foxhole · 25 Jan 2020

Why wickes, plenty cheaper , bought mine cheap on Facebook.
Have 450mm in my loft , false economy to skimp on insulation .

oldbutnotdead · 25 Jan 2020

Plus if you've been good and notified Building Control about your roof replacement they'll want to see 300mm up there unless there's a very good reason (cost of rockwool isn't a very good reason). Matter of interest, what was on the roof before- slates or tiles? (If slates then your concrete tiles may be a bit heavy for the rafters)

diynot

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local

Loft insulation please

Leofric

Similar threads