Conservatory Foundations / Company approval

[keithbucknall]

Guys,

I wanted to run this past you guys first as I think everyone here provides some fantastic advise. At present we are looking for a 3.2m (d) x 3.8m (w) and a number of conservatory companies have come round from Durabase still prefab's to normal concrete foundations.

The concrete foundations that one company have provided state it is a re-enforced concrete raft over trench - I assume this is ok?

They also mentioned that the DPC is mixed into the concrete first similar to plasticizer and then they use bitumen paint instead of traditional DPC - is this an ok method? They mentioned this is easier and saves with any issues if the DPC gets ripped.

The brickwork is then cavity walls and the floor is then interlocking chipboard on rafters which I find strange.

I would welcome your thoughts and comments.
Many thanks

Keith

 

[amwc]

Is this all from one company?

I'd say they were going to waterproof the concrete with an admixture then paint over it then insulate and screed the top? this is a lot easier than a dpc sheet and is ok if done right but has its own problems.

I cant really see why a company would specify a rc raft and joists though? unless it was added damp protection.

The trench and raft scheme is normal for cavity walls. Although they may get away with just the raft on good ground.

 

[Static]

All sounds odd to me..
Maybe you should ask to see some details of this from them.. or even to inspect a finished job which is similar (chat to the owner and ask if any probs)

 

[noseall]

Connie companies spare little amounts of their budget on the bases.

This is a fact.

Many connie bases are built with a footing beneath the outer skin only, then they lay the concrete slab and build the inner leaf off the slab. Poor as p1$$.

When i did mine i dug and laid a 550mm wide foundation and built the inner and outer leaves up to dpc off the foundations. Laid a 1200 gauge dpm and cast the slab.

Why settle for less?