replace wood floor with concrete?

[noseall]

If this is absolutely necessary

No.
Just ensure that your DPM is adequately lapped up the wall and deals with all that is within the thickness of the floor detail. If it was your intention to batten the walls with a DPM behind then leave enough lap on your floor DPM to lap behind the wall visqueen.

 

[legepe]

Just ensure that your DPM is adequately lapped up the wall and deals with all that is within the thickness of the floor detail.

Thanks a lot noseall... understood..

 

[endecotp]

Wow, that was an intelligent comment. Okay, I may be wrong, so now expand and correct me; I'm always happy to learn.

Sorry, but I was in the middle of something else and didn't have time for a proper reply - but I thought I had to correct that.

Thankfully noseall has expanded on it.

It doesn't matter where you heating is coming from, UFH or radiators; you need to insulate the (external) edges of a warm slab.

 

[Doggit]

It doesn't matter where you heating is coming from, UFH or radiators; you need to insulate the (external) edges of a warm slab

In that respect, I'd agree with you completely, and I did ask what he intended to finish the floor with, and hadn't got a reply, so assumed it wasn't a warm slab.

 

[legepe]

Sorry guys... i never went as far as thinking what to finish the floor with.. my concern was with what was going to be under it..

 

[legepe]

All EXTERNAL walls require an insulation upstand. The only way around it is if you are building new cavity walls and are taking the cavity insulation down and into the sub-DPC trough.

Its a mid terraced house.. If Im correct internal walls also need an insulation upstand... or no?

 

[endecotp]

An upstand against the internal walls will reduce heat loss from the floor slab into the ground via the wall. I don't know whether it is actually required by regs though.

 

[Mr Chibs]

I've done the opposite, ripped out the concrete floors and replacing with wood, the concrete was old and layed on crushed brick and ash base, and was bringing damp up, as the internal floor was higher that the DPC.

1900 house, solid brick.
For me ventilation is key, so re-instate the air vents replace/repair sleeper walls, fit joist hangers and fit new joists/floor.
Slip DPC under anything wood that sits on brick.

I will be insulating this floor once plumbing has finished.

Since doing this, my house is a lot drier. I have a tar/bitchumen DPC.

 

[legepe]

Well finally got my floor down see pics... very happy with result.. there is 150mm of type 1 hardcore, around 20mm of sharp sand, dpm, 150mm of insulation, dpm, self leveling concrete.. which is absolutely bang on level..

For me ventilation is key, so re-instate the air vents replace/repair sleeper walls, fit joist hangers and fit new joists/floor.

I guess you was having damp rising because there was not dpm

 

[Footsoldier888]

Great effort legepe.

Just a couple of questions. Did you have to put expansion gaps in atall? And where the dpm is against the wall, do you just bond it to the wall or does it have to be chased into the brickwork???

 

[legepe]

Did you have to put expansion gaps in atall? And where the dpm is against the wall, do you just bond it to the wall or does it have to be chased into the brickwork???

Its got 25mm upright insulation on all walls, I didnt put expansion gaps.. just made a couple of cuts around 1/3 through concrete so when it cracks hopefully it will crack there... the dpm is only to hold the concrete.. it needs to be taped up properly where necessary... walls are injected with dampsolve