Damp proof level

[Vijay]

Hi,

 

Is it the correct way to have the damp proof course at finished floor level, which is 150mm above the external ground level?

 

I've attached a pic where I've had to raise the height of the B&B floor so it sits on top of a complete ICF panel but then that leaves me with the waterproof concrete (that's used as the damp course) at the external ground level. The only solutions I see are to use an extra 150mm of waterproof concrete to raise the damp course to 150mm above the external ground level (so the waterproof concrete is at the same height as the FFL) or to have some sort of external ground drainage (which I don't like the idea of).

What do you guys think?

[PeterW]

Assuming your radon barrier is also the DPM I would go straight across between the two layers of insulation and straight out at DPM level with that - you may want to check your ICF levels anyway as currently you will have to cut down the blocks for every doorway as they are mid height and not level with the top of the block. 

[Vijay]

Hi Peter,

But if I went straight across with the radon barrier, that would be at external ground level and would that not be too low? (I assume it would have to be 150mm higher than ground level). Also if the radon barrier went straight across the two layers of insulation, that would prevent the concrete from bonding to each other.

 

Every doorway needs a timber former made up anyway so I don't think cutting of the panels (using the Polarwall system) will be an issue? 

[jamiehamy]

Vijay ,  wouldn't you just put the radon barrier up one more course of icf? Ours was slightly different as we're building inside a tank but we brought the dpm  up to the next course above the concrete topping. I wouldn't put it across the concrete tho for reason you give.  

[Vijay]

Hi Jamie,

 

I think putting it up would work too, Alan normally puts it down so that's why we've gone that way.

 

It's the waterproof concrete (that I've coloured blue) that I wonder if I need to raise higher by 150mm

[MrP]

I would check to see the manufacturers standard details depending on who is supplying your ICF. Most manufacturers have a full set of pre-designed details for most situations. For example see attached detail which i think details what you are trying to understand.

PWD014.pdf

[Vijay]

Thanks MrP, that's exactly what I was looking for

[Vijay]

I think this looks right now? Blue is waterproof concrete

[jamiehamy]

Yup

[Vijay]

Cheers Jamie   Might actually get there!!!!!!!!!!!!!!!!!!!!!!!