concrete floor for house extension

[LAF]

Not really a farming question, apologies, but it is related... We are building a livestock and workshop shed and I'm comfortable with a floor of 6" stone and 6" of reinforced concrete on top, this seems generally what people do. We are also extending the house and I got this drawing from the architect for the slab under a 2-storey timber frame. 9" reinforced ! And 3" more floating on insulation !! That seems nuts to me, a 9" slab could take industrial load, but the floating screed won't take much at all. Is it them or me that doesn't have a clue ? Or both !

 

[LAF]

this is the architect's drawing

 

[upnortheast]

There is a lot of over designing goes on ( called covering my arse )
Had a signle story sun room built last year. Spec was to go down 800 mm / 1000 mm round the outside. lay 200mm reinforced raft in bottom of hole.
build up from there. Took 15 tonne stone to fill up the void, insulation then 150mm floor on top

So very similar to yours

Beyond me why strip founds were not acceptable.

 

[br jones]

on good ground 150mm sub base ,100mm concrete ,100mm insulation 60mm of floscreed

 

[Bongodog]

Not really a farming question, apologies, but it is related... We are building a livestock and workshop shed and I'm comfortable with a floor of 6" stone and 6" of reinforced concrete on top, this seems generally what people do. We are also extending the house and I got this drawing from the architect for the slab under a 2-storey timber frame. 9" reinforced ! And 3" more floating on insulation !! That seems nuts to me, a 9" slab could take industrial load, but the floating screed won't take much at all. Is it them or me that doesn't have a clue ? Or both !

Get another architect, this one is talking rubbish

 

[Bongodog]

Get another architect, this one is talking rubbish

I didn't type rubbish, the forum changed what I said

 

[bobk]

Get another architect, this one is talking rubbish

Bollox , that works

 

[Daddy Pig]

I built a single story sun rum a couple of years ago ,150mm subbase, insulation and 50mm screed made from beach shingle with a bit of sand. then tiles on top. worked fine.

 

[Kidds]

Dig a hole and get the architect or building control to look in it before deciding what concrete is needed.
If it is good ground they will lower the spec. Son found this out the hard way

 

[TheTallGuy]

Never rely on architects... use a proper structural engineer.

 

[Lakesdigger]

It does look as if the spec is for a structural floor/raft though they usually have thickening round the edges but you're plan doesn't let us see this detail and so the building is built off the floor. Unless someone knows something about how you're original building is built and thats why it's designed this way the best thing to do is dig down beside existing house wall to find foundations and see what they consist of. You can then work from this which if its strip founds and not silly deep will be much simpler.
Conc then insulation and then screed is becoming the norm for floors and the way to go with underfloor heating which imo you may as well do on ground floor at least. He's way under spec on insulation thickness with building regs now mind.

 

[Exfarmer]

I had exactly the same experience 3 years ago building my orangery. The floor itself does not carry any load as we already had the walls around the patio. Thankfully the builder of this 2 foot stub wall either had the foresight or the same idiot architect, as that sat on a 3 foot foundation cut into solid limestone!
after the baewe went in a skim went over the top for the tile floors. absolutely crazy. If it had been today I would have cut a nuclear bunker underneath.

 

[puppet]

I had exactly the same experience 3 years ago building my orangery.

I have also found it frightfully difficult to get the right spec for the new library extension and the servants quarters.

Have we moved from a farming forum to Tory party expenses claims?