DPC Mortar - Look ok?

[Signor Bob]

Extension was built last year. I've noticed you can see under the dpc a bit in places and the top of the brick, possibly where I've used a jet wash on the stone pavers below and its removed some mortar but may have been like that anyway... is this structurally ok?

 

[stuart45]

That's not a problem.

 

[Ivor Windybottom]

Absolutely fine. Some houses have it obviously visible, jutting out. Others have it set back a bit and pointed over, arguably bridged but in reality absolutely fine. Yours is somewhere in between!

 

[stuart45]

Technically, the DPC should be 5mm out each side of the brick. It's why the DPC is 112.5mm for a metric 102.5mm brick.

 

[^woody^]

Technically, the DPC should be 5mm out each side of the brick. It's why the DPC is 112.5mm for a metric 102.5mm brick.

Does anyone actually do that? Or perhaps, does anyone actually want to see that? It always looks unfinished and wrong.

 

[Munroast]

and the entire house might slip off

 

[noseall]

Does anyone actually do that? Or perhaps, does anyone actually want to see that? It always looks unfinished and wrong.

Christ no!

BC's and designers frowned upon that yonks ago. We use 100mm DPC for that reason. "...no material shall protrude into the cavity..." They are there for a reason.

 

[Deluks]

It does provide a bit of leeway for those walls built using 'wavy string'

 

[stuart45]

Does anyone actually do that? Or perhaps, does anyone actually want to see that? It always looks unfinished and wrong.

I've never known anyone do it. Most trowels I've worked with don't even know the difference between 100mm and 112.5mm damp. It's normally flush with the outer skin. Most parts of the the country bed it, but on a lot of jobs in the West it's laid straight on top. It's allowed by the NHBC, provided the building is no higher than 3 stories.

 

[opps]

Given that the point of the DPC is to stop capillary action, I do not see how it being set back by a couple of mm will cause any problems. Any such capillary moisture surely will evaporate off in the day.

 

[stuart45]

It's just one of those technical things the NHBC put in their drawings and regs, so I suppose on site they have to supply 112.5 DPC to keep them happy.

 

[^woody^]

I thought DPC was supposed to project into the cavity to hold the insulation up? May be wrong though.