Thermalite Turbo blocks u values

[sleeper341]

Hi,
I am building an extension which is in 2 parts, one section set at a slightly higher level than the other (one part is at current floor level, the other part is lower to help prevent light loss from next door) the wall between these 2 sections is mainly internal but has about 200mm projecting above the lower level flat roof.

Can I build this wall from Thermalite Turbo blocks 215mm deep? I ask as I think that the BCO will say that the projecting part will need to meet the required U value for an external wall (0.28 ) as it is 'outside'. From what I can see these blocks have a u rating of 0.11 so they should be fine but i'm no expert. If I cant use these then it will have to be a cavity wall and I'm trying to gain as much extra space internally even if it is only 4 inches in difference between a cavity wall and using Thermalite blocks.

Any help is appreciated.

 

[DevilDamo]

Hold on a minute...

 

[tony1851]

From what I can see these blocks have a u rating of 0.11

If only they did, life would be a lot simpler :lol
Try 0.5

 

[sleeper341]

I've spoken to my BCO and found that I cant use them. Cavity wall from top to bottom inside it is (or installing a lintel on top of a block wall and then building a low cavity wall on top of this - seems like too much aggravation).

Thanks for reading though.

 

[tony1851]

If you used the 215 block, had render on the exterior and applied some insulated plaserboard internally to achieve the requisite U-value, you could end up with a thinner wall.

 

[freddiemercurystwin]

If you used the 215 block, had render on the exterior and applied some insulated plaserboard internally to achieve the requisite U-value, you could end up with a thinner wall.

Barely, save an inch I guess.

 

[tony1851]

Fair enough; looking it up, Kingspan says 52.5mm product thickness - probably not much in it.