Insulation spec

Tomred272

Hi,

In process of going to tender on our house and as part of the process I have had a consultation with an insulation specialist. I have tried to sumarise it down as follows but would be grateful for an independent advice. He has also recomended on airtightness but I have kept this post to insulation. For reference we are going with Geothermal, UFH and heat recovery / ventiliation.

Floor
Ground Floor: 125mm foil backed polyurethane on top of sub floor.

Wall
Block Wall Structure: 100mm outer leaf, 200mm cavity, 150mm inner leaf
Fill the 200mm cavity with Grey bead insulation pumped with glue
Teplo ties
Use 75mm kingspan as cavity closure

Cold bridging from foundation
One row of Quinnlite blocks (B5) opposite the floor insulation on the inner leaf and on all interior walls
20 mm Kingspan between the side of quinnlite blocks and floor screed

Sloping Ceiling
All insulation from eaves to ridge
Almost fill the rafters with spray-in Biobased 501 (an open cell foam)
Fix 100mm kingspan below rafters
Install plasterboard up slopes across collar ties and down other sloping ceiling

Roofing membrane
Breathable membrane such as Solitex Plus
Batten with rafter then instal counter batten to take slate

Cavity Closure at top of walls
Cement fibre board

Dormer Windows
Fill the stud with Biobased 501
Line the inside of the dormer with 60mm kingspan
Install plasterboard


Many Thanks

Carlow52

Interesting spec:)
Couple of queries:
What type is house: dormer bungalow/2 storey/?

if 2 storey whats the !st floor?

What finish on inner face of external walls?
What type are internal walls?

Whats the plan for getting airtightness around the window and door frames?

Have you considered an insulated foundation?

How did u arrive at the wall spec: have you considered an ICF build?

Tomred272

Thanks Carlow52,

It's a 2 storey house

The 1st floor is to be a concrete slab

Plaster wall finish on the internal walls
Internal walls to be block (albeit I have not given this too much thought)

Airthightness around windows & doors - Initial plan was to use expanding foam then seal foam with CT1

I considered all sorts of construction methods including ICF and eventually decided on Block with a large cavity. ICF looks good but also has some draw backs. It was a close call.

To be honest I do not know anything about an insulated foundation but will do a bit of research.

Thanks

Carlow52

Foam and CT1 will not do IMO
u need to consider some form of airtight tape

sinnerboy

200 cavity will require a structural engineers design especially for - wall ties - roof connection - window opes - floor connection

Better to use AAC blocks ( Quinn lites ) for the entire rising wall - or better again use an insulated foundation system ( google for that )

You can't "almost fill" a cavity with spray foam.

http://www.youtube.com/watch?v=VFjxWdPPY1Q

Better to locate the supplemental insulation layer above the roof timber - keep them warm

Overview

A building in Ireland loses heat via

1. the build fabric walls ground floor roof windows external doors
2. air infiltration

It gains heat via
3. Solar gains
4. Internal heat gains

Your post deals with parts of item 1 above only

You need a good building professional who can use DEAP to weave all 4 together .

And/or look here

Carlow52

Nice clip on the spray foam: One would need sign off by SWMBO before getting it done:)

Did the elec cables look sleeved or conduit-ed at [ 0:21 through 0:45 ] seconds?