What blocks & what catnip

[trowelandhawk]

I am building an outside office in rear garden. I have dug footings (800mm wide x 500mm deep) and concrete will be poured soon ( that was a shock at the price of concrete for footings)Next stage is the building itself. I am not sure what blocks to use.
1. Is it ok to use thermalite blocks below ground, straight on top of the foundations.
2. Is it ok to use thermalite blocks as the external skin
3. The cavity is 100mm,do I use 100mm insulation or thinner.
4. The total width of cavity is 300mm. What with catnic lintel do I use, does that have to be 300mm also. I know it has to be 300mm longer than the span.
Thank you in advance

 

[trowelandhawk]

Anyone?????

 

[freddiemercurystwin]

It is a poor show, some of the members here are just plain rude and lazy sometimes. Fancy not answering your very important post on a Sunday, you'd think some of them had nothing better to do.

Still, at least you actually bothered to reply in one of your own threads for once!

 

[lostinfens]

I'm fairly sure that it is ok to use thermalites below ground and externally if rendered etc--but personally wouldn't touch em with a barge pole. They are in my humble opinion rubbish and are suitable as hardcore at a pinch.
I'd use trenching blocks under ground (which oddly are thermaliteish), engineering brick to dpc then plasmor fibolite above ground.
If you go to plasmors website, you'll find links to their technical help. They will advise you as to your requirements to reach your desired u-value.
Catnic & others make lintols for 100mm cavity & wider.

 

[cotswoldbuilders]

Your foundations are wide enough, no wonder you used so much concrete.
Id use concrete blocks.