How to fill the gap between floor and wall?

[bobby5000]

Hello,

There is a gap between the concrete base and the walls in my rooms where skirting baked have been removed. DPC is a bit below the floor level and there is no DPM in the floor. I want something to fill the gap between the base and the wall so that it isn't a haven for creepy crawlies behind the skirting board. Also so that there isn't a drop underneath the carpet or laminate that I install around the edges of the rooms.

Trouble is, I don't want to bridge the DPC which, again, is below floor level and you can see some of the brick below it.

Expanding foam is an option but is that definitely water resistant? Will it stay that way or break down over time?

Perhaps concrete mixed with a waterproofing ingredient?

Rockwool - is this sufficiently water resistant or will it just suck up moisture from below the DPC?

Other?

It is quite messy in the gaps, with buts of rubble, sand, uneven concrete surfaces, etc. I've tried hoovering out as much as possible, but I don't think painting in the gap will work.

 

[mcprinter]

Can you get some pics?

 

[JohnD]

Hello,

...there is typically no DPM in the floor...

What does "typically" mean?

 

[bobby5000]

What does "typically" mean?

Sorry, that was a typo.

 

[JohnD]

Strange that the floor has no dpm and bridges the DPC. Was the floor added after the house was built? how old? Was it a garage?

I think you need to scrape out the gap to expose the DPC and push a vertical strip of DPC into it, covering the DPC and the bricks above it so it will no longer be bridged, and rising above floor level so it will tuck behind the skirting.

You could then pour fine concrete into the gap, or S&C if the gap is very narrow. If it is wide enough you could push foam expansion strip in first.

 

[bobby5000]

Strange that the floor has no dpm and bridges the DPC. Was the floor added after the house was built? how old?

I think you need to scrape out the gap to expose the DPC and push a vertical strip of DPC into it, covering the DPC and the bricks above it so it will no longer be bridged, and rising above floor level so it will tuck behind the skirting.

You could then pour fine concrete into the gap, or S&C if the gap is very narrow

It was built in 1961. I think the legal requirement for DPM was not until 1965 and sporadic after that for a while.

There is a gap between the floor and the wall and you can see the dpc in the brick a bit below. I don't think the floor was added later as some of it has marley tiles on. It was either just the way they did things at the time or was done incorrectly.

There is no rising damp evident anywhere but as I say, I want to fill the gap ideally as I've been some bugs manage to get in.

 

[bobby5000]

I will post some pictures later

 

[bobby5000]

Here are some photos.

 

[JohnD]

I reckon you could scrape that out with some sort of iron hook.

A builders canister vac will be better for sucking out the dust and rubble (more powerful than a domestic and will not be damaged by the grit)

 

[bobby5000]

But even after I've scraped it out there is still a trench between the floor base and the wall, with the DPC below the floor. What moisture resistant material can I fill the gap with?

 

[JohnD]

Strip of DPC against the wall, then fine concrete. Use foam expansion strip if there is room.

You can make a runny mix, it will sag a bit, just press it down and pour in some more. Smooth it off to match the floor once it has stiffened.

The fluid mix will press the DPC tight against the wall. Leave it sticking out and you can trim it off and tuck it behind the skirting.