dpc?????

andybharris · Post by **andybharris** » Fri May 01, 2009 6:06 pm

Hi all, after having had a damp wall in my dining room (result of bad pointing) i looked at my dpc and found a newer one above the level of my drive but covered with cement render I have since removed the render over the dpc and i found what looks to be the original hidden under my driveway. can anyone shed some light as to why i should have to lots of dpc i have since dug down to expose the lower dpc and the wall seems to be drying nicely both inside and out Cheers

Post by **ultimatehandyman** » Fri May 01, 2009 7:53 pm

Never seen that before.

How old is the house?

andybharris · Post by **andybharris** » Sat May 02, 2009 6:41 pm

ultimatehandyman wrote:

Never seen that before.

How old is the house?

early 1900's

Post by **ultimatehandyman** » Sat May 02, 2009 6:47 pm

Well they never had plastics back then, and that looks like plastic to me and so it must of been retro fitted.

Is the wall a cavity wall or is it solid?

andybharris · Post by **andybharris** » Sat May 02, 2009 6:52 pm

ultimatehandyman wrote:Well they never had plastics back then, and that looks like plastic to me and so it must of been retro fitted.

Is the wall a cavity wall or is it solid?

indeed the top one is plastic, the bottom one is definately not, the walls are solid, the lower dpc was under the driveway and the newer top one was only just above it but was covered by the render on the outside of the house

Post by **ultimatehandyman** » Sat May 02, 2009 9:21 pm

They often used slate as a dpc in some houses.

Having a plastic dpc fitted like that would not be cheap and would take ages.

I'm wondering how they could successfully retro fit the plastic dpc in a solid wall (double brick) as it is hard enough in a single skin wall.

andybharris · Post by **andybharris** » Sun May 03, 2009 10:06 am

ultimatehandyman wrote:They often used slate as a dpc in some houses.

Having a plastic dpc fitted like that would not be cheap and would take ages.

I'm wondering how they could successfully retro fit the plastic dpc in a solid wall (double brick) as it is hard enough in a single skin wall.

yes its certainly a mystery to me, the plastic dpc only goes into the wall one brick layer in

stuart45 · Post by **stuart45** » Sun May 03, 2009 10:22 am

Is it a proper DPC, or the end of a plastic sheet that was pushed into the joint and then pulled down to protect the wall because they were going to raise the ground level?

andybharris · Post by **andybharris** » Sun May 03, 2009 10:26 am

stuart45 wrote:Is it a proper DPC, or the end of a plastic sheet that was pushed into the joint and then pulled down to protect the wall because they were going to raise the ground level?

looks like a proper dpc but i am no expert

, however it hasn't been pulled down over the bricks

stuart45 · Post by **stuart45** » Sun May 03, 2009 10:29 am

There looks like a lot of it sticking out at the side. Normally a DPC would be flush with the face, or is that just the way the photo shows it?

andybharris · Post by **andybharris** » Sun May 03, 2009 10:38 am

stuart45 wrote:There looks like a lot of it sticking out at the side. Normally a DPC would be flush with the face, or is that just the way the photo shows it?

no you are correct, the part you refer to is at the very rear end of the house but this part is a way above ground level and there is some sticking out, there is also alot sticking out at the very front end of the house although this part of the house is well above ground level also.

stuart45 · Post by **stuart45** » Sun May 03, 2009 10:49 am

It could be that they have cut out with an angle grinder and couldn't push in as far in places. They then rendered over it and didn't bother to cut it flush.

Raf · Post by **Raf** » Wed May 06, 2009 10:19 am

would that be done one brick at a time (pretty much)? a lot of work there then!

andybharris · Post by **andybharris** » Wed May 06, 2009 5:15 pm

stuart45 wrote:It could be that they have cut out with an angle grinder and couldn't push in as far in places. They then rendered over it and didn't bother to cut it flush.

the plastic is cut flush where rendered over, the parts showing excess are the none rendered parts of the wall

python · Post by **python** » Sun May 17, 2009 5:18 pm

the only thing that strikes me is someone's bodged attempt to put in a second, raised, dpm in because they wanted to raise the ground level, or the ground level had allready been raised.

They did this, later it was rendered over. The job was not good enough leading to your damp problems, then re-lowering ground level that you have done has solved it.

Dunno if this is correct, but it's possible.