Blocks under soleplate

[daunker]

I'm doing a conversion and building timber frame inside existing 140 dense blockwork building

 

I've read about problems with condensation on soleplate occuring. What is the standard block below soleplate. I had been hoping to use thermalite or equivalent.

 

I looked up marmox thermoblock, and they have detail below. Whilst I can see there is advantage to having it below soleplate it doesn't mitigate the cold hitting the front face of the soleplate. I had thought that air temperature on this face might be more prone to dropping below the dew point and does this not have same condensation risk as from below?

 

If condensation is not an issue then I can sort out cold bridge with rigid insulation on internal face of the frame?

 

The thermoblocks are expensive and I was rather thinking that whilst they may be a better option. Is it reasonable to just have thermal lightweight blocks below soleplate. And are there any specific ones recommended. I've read on here of many 'blowing out'. It's only single storey and doesn't support roof etc.

 

Thanks!

Edited October 23 by daunker

[Mr Punter]

7.3N Aircrete blocks will be fine.  Don't shotfire the soleplate into them.

[daunker]

Lovely thank you, I drilled and chemfixed previously which worked well so will repeat that then 👍🙂

[daunker]

Was reading on here into the small hours, and thinking why don't I put the 50mm celotex on the outside of timber frame rather than the inside. 

 

Ie: existing Block, 25mm ventilation gap, 50mm celotex, breather membrane, 12mm ply, 140m timber frame with frametherm, ply, vcl, plasterboard.

 

Could then insulate the soleplate externally and also the entire Frame? Is there a reason more don't do this?

Edited October 24 by daunker