Where to put the DPM/DPC

[RogerS]

Starting to think about LOML's Playspace (oops...sorry, Orangerie . Mainly glazed, there will be some dwarf walls with a couple of courses of ashlar sandstone. An inner skin from blocks or timber to make it look pretty inside as well. But she wants hard-standing all the way round on which to put her plants/outdoor working area but if I put the DPM underneath the whole concrete plinth ...that doesn't seem like a good idea to me.



But what to do ? This ?



Here's an unmarked image for anyone with a solution



Also where does the DPC go please ? NB two long walls will have two sets of doors in each and the ends will have a set of doors apiece.

TIA

 

[RogerS]

46 views and no suggestions ?

 

[Deejay]

Morning Roger

Do you want a membrane below the hard standing? It will get rained on and absorb moisture anyway.

Cheers

Dave

 

[Malc2098]

A Level Woodwork, me, Rog! I wouldn't know what to suggest.

 

[Phil]

46 views and no suggestions ?

Apologies Roger, I am not a builder and I could not understand the drawings ............

Maybe MG will be around soon.



Phil

 

[RogerS]

Morning Roger

Do you want a membrane below the hard standing? It will get rained on and absorb moisture anyway.

Cheers

Dave

That's a good point, Dave. I seem to recall Mike having a separate slab now...

 

[Robert]

Think I'd go with your second option but change the external slab to have a slight slope for run off.
Of course you know you had no replies because we are all waiting for our resident expert to tell us how it should be done

 

[Rod]

I was waiting for Mike but I would go for 1 plus a DPC 2 bricks up on your walls.

Rod

 

[RogerS]

I was waiting for Mike but I would go for 1 plus a DPC 2 bricks up on your walls.

Rod

My thoughts were that the slab would get damp all the way through to the inside with this option.

 

[Gone fishinf]

We are waiting for Mike G

 

[Rod]

Concrete is pretty water resistant and should run off/dry on the top surface.
Underneath it's subject to water tables, ground water and possible water pressure.
To be even more water resistant use air- entrained concrete.

Rod

 

[old]

DPC is to stop rising damp so under the whole slab gravel at edge to cover visqueen then angle the slab away from the walls where hard planting area is, to take water clear of building.

 

[HappyHacker]

I would put two slabs as per diagram 2 with the DPC also going under the walls and up to a DPC about 6" high on the inner wall if the inner wall is to be plastered. Otherwise just under the walls or up the inside of the cavity and into the inner wall . This will stop any rising damp and also any damp coming under the walls. I suspect that if you have just one slab damp will come through the concrete under the wall.