Warm flat roof and cold bridging wall plate advise

[oldman2]

I just had a small flat roof extension built of brick and thermolite block with a 90mm celotex warm roof and could do with some advise on how the insulation should have continuity between the top of the walls and the warm roof.
The cavities are filled with loose fill mineral wool to the top of the blockwork.

The first side in the picture below had the joist ends cut flush with the brickwork, 90mm celotex was tight fitted into the gaps between joists above the bricks and a 40cm facia board nailed onto the joist ends just overlapping the top course of bricks.

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From inside it looks to me like the void needs either another packing of celotex or loose fill taking right up to fill the void?

The second side has a window and lintel and I think is a little shy of loose fill above the lintel anyway.

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The brickwork has a joist above it and one above the blockwork with noggins in between but no insulation to speak of at all in this void.
The wall plate above the blockwork seems to serve no purpose other than to fill the gap to the joist, but through this small gap I was able to get my led flexible lamp and apart from a small amount of loose fill that looks like it got there via the cavity closer gaps, 2 loose bricks and a 1 foot bit of celotex at a 45 degree angle which was either throw away or was supposedly held upright by the 2 bricks the void is just, that an empty void.
I will assume that the same insulation criteria will apply here as in my first question, but how to instal it now the jobs finished?
Assuming for now the loose fill is in place all the way to the top of the blockwork, there should be at least on continuous run of 90mm celotex between the outer joist and the one visible on top of the blockwork shouldnt there?

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I guess that if say 3 of the top cut down blocks were removed on each side of the noggin, that insulation could be inserted in small amounts.
As far as the builder is concerned the job is all boxed off now awaiting the BCO signoff with just a couple of small items to address.

 

[noseall]

We build up the masonry so that it finishes just short of the deck, then fill the cavity with insulation so that the insulation meets the insulated deck.

 

[oldman2]

So would you agree Noseall, that the only realistic option open now is to remove most of the top row of blocks and insulate behind the joists with celotex and or loose fill, then reinstate the blocks with maybe leaving out the redundant wall plate and using say full sized blocks or at least taller ones than there at present. Assuming the blocks to have better insulation properties than a timber wall plate.

Making sure of course that the cavity above the lintel is filled with insulation which I doubt.

 

[noseall]

Just pack the void with celotex. There isn't a structural need for the wall to carry on but it is more robust and fireproof.

 

[oldman2]

He removed a couple of blocks from left and right and cleared out the 2 unused bricks that had been left in there then filled the void with a roll of fibre insulation.
To fill it with celotex would have meant removing the whole row of blocks, the BCO suggested the loose fill would be ok.

All done now and I'm happy its insulated.
There was one bit of 30mm celotex in the void, how that token bit got there I dont know but its staying and the loose fill is around it too.

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[manich45]

Just pack the void with celotex. There isn't a structural need for the wall to carry on but it is more robust and fireproof.

Hi,
I was wondering the same! Do you mean raise the masonry to the deck on the outer skin of masonry between the joists?
do we stop short of the deck and joist or mortar upto,touching them?

Thanks...