Is my floor too low for DPC?

[Georgie73]

We hacked all the plaster off the wall and removed skirting. The skirting was rotten on the external walls.

The floors are concrete and the DPC is visible - it is about an inch above the floor. Would this be the reason why the skirting was wrotten?

 

[vinn]

What material is the DPC?
Are the walls solid?
Does the concrete floor have a membrane showing at the edges?
Is the internal FFL higher than the external ground level?

 

[Georgie73]

It looks like the traditional black stuff that comes on a roll.
The walls are brick and have a cavity
FFL?

 

[Georgie73]

The internal floor is higher than the outside of the house (gardens/pathways).

When fitting new skirting, should we run some DPC over the floor an up behind the skirting?

 

[vinn]

Are you perhaps confusing a DPC with a DPM? My apologies if your not.
The DPM is the sheet membrane that should be installed under all concrete floors - it typically laps up the walls at the edges of the floor by about 50mm to 75mm. Can you see any signs of a membrane?
Whats often done to protect skirting is to cover the back of the skirting with DPC material before fixing the skirting to the wall. But if i understand you, you dont run DPC across the floor.
Cavity insulation can become wet & soggy and cause interior damp.
Cavity bridging can be caused by rubble piling up (above the DPC level) inside the cavity & also cause damp.

 

[Georgie73]

Hi

Yes it is the membrane I can see.

So if I put some DPM behind the new skirting - it should get damp and rot?

 

[vinn]

You are still confusing the DPM ( a large sheet of plastic membrane) with the DPC that is a black plastic material that comes in rolls of 100m wide or more.
The DPC is laid in the wall below a course of bricks or blocks.
The DPM goes under the concrete slab.

You can put any kind of plastic cover behind the new skirting - it will form a barrier to prevent damp reaching the skirting.
But you have not yet identified the cause of the rot and damp so you would be best advised to post a photo of the floor to wall junction, & read the masses of threads about your kind of question.