Slabbing and insulating what options?

Jollyman

Ok getting to the stage where i need to start slabbing and insulating! I must talk to my engineer but would like to hear what others are doing; for the down stairs joists what insulation is to be used and a foil back plaster slab 12.5mm or 15mm?

Upstairs in the pitched roof rockwool/fibreglass or kingspan board and foilback or normal plasterslab?

Dividing studs what insulation and what sort of slab?

I am putting the insulated slab on the internal side of all external walls is the aeroboard version as good as the kingspan?

sydthebeat

i would recommend 'slabbing' out and wet rooms with WBP 'marineply' rather than plasterboards, in the case the walls are ever tiled.

'aeroboard' (polystyrene) drylining hasnt as good thermal performance as 'kingspan' (polyisocyanurate)......

whatever insulation you use needs to comply with regulations. This really should be decided before construction begins, and allowances made to suit.

gman2k

contact xtratherm or kingspan insulation direct, and ask for the technical dept. Describe the building methodology - floors, walls and roofs and they will specify the exact products needed to comply with building regulations.
Forget about about older 'white' aeroboard products, as you would need extraordinary thicknesses to comply with Part L.
Reducing cold bridging is also very important, as is airtightness.

250882

its also evry important and not very often mentioned but if you have a cold attic space avoid using thinner high performance insulations between the ceiling joists as they make the timber into a cold bridge. Its better to use insulation between and above the slabs or using insulation backed plasterboard below.

bbam

Incidentally I have a rep coming out this week from an insulation company and would like to get some BTDT inputs..

1. What insulation if any, would you use between ground and first floor, my partner likes the idea of rising heat from the living space to the bedrooms but I'm worried about noise transfer.

2. Again in the stud walls on the first floor, I've been advised to insualte the bathrooms for noise, what have others done? Would you insulate all stud walls?

I understand what I'm working towards on the outer perimiter of insulation against the "outside" cold.. It's just the internal insulation I'm unsure off.

Thanks
bam

gman2k

To insulate a ceiling/ FF;
Mass is key to sound transfer, and air tightness between the two areas is also paramount.
Typical well soundproofed timber floor;
Timber floor finish - laminates/ semisolids etc on
proprietary foam roll on
cork amt insulating layer such as regupol
on joists
infilled with dense rockwool (sound) insulation
2 layers plasterboard staggered joints skimmed
all service opes well plugged

http://www.rockwool.co.uk/sw59440.asp
the details described here are more suitable for seperating different dwellings - apartments