DPM across door threshold

[realtek]

Hi all,

When we put down the DPM and poured the slab the DPM around the doors ended up being pulled tight across the internal leaf of the door threshold, I think because we made sure the DPM was quite flat on top of the sand.

I assume the only way to solve this is to cut it and patch it up around the door thresholds?

Not sure how it would usually work because of the corners on the two bricks either side of the threshold - hard to find info about this.

In hindsight it the DPM in this area usually kind of bunched up so it would not be pulled tight?


Thanks

 

[Himaginn]

Did you use an upstand of insulation around the edge to prevent cold bridging?

 

[realtek]

Did you use an upstand of insulation around the edge to prevent cold bridging?

Yes we did, Cheers

 

[Himaginn]

So wouldn't that upstand of insulation held the DPM in position?
If not, how much damp would you get across the insulation? I ask because I don't know the answer. Perhaps more experienced people might offer an opinion.

 

[r896neo]

Is this an exterior door threshold?

Thresholds would normally be built with a lintel effectively closing the cavity and they would have a dpc of their own enveloping them and directing any penetrating water outside. Much like how you would fit a window cill.

The interior floor dpm would then run up the back of this dpm

 

[realtek]

Is this an exterior door threshold?

Thresholds would normally be built with a lintel effectively closing the cavity and they would have a dpc of their own enveloping them and directing any penetrating water outside. Much like how you would fit a window cill.

The interior floor dpm would then run up the back of this dpm

Hi,

Thanks for this, so it sounds like you would normally just overlap (and seal) the floor DPM and one over the threshold which extends to the outer leaf?

I've filled the cavity with concrete under the door opening and poured the slab and the screed will go across the cavity to the outside leaf (which has the perimeter insulation to stop cold spots).

So effectively the same as using a lintel as you said.

Cheers

 

[r896neo]

Where do you intend to sit the door? It would normally sit against the rear of the inner leaf and so the outer leaf should be damproofed to shed any water outside and the internal floor damproofed to prevent and dampness creeping inside the door.

By making the threshold the way you have you'll have to make sure you have either a dpc or a cill under the door to shed water away from the base of the door. Can you post a photo of what you have been left with?