What to do with damp wall?

alinois

Hi everyone,

My house has a recessed front door and on each of the sides my wall is always damp near the floor blocks to the point where I'm now seeing some efflorescence grow. Here are two pictures of what I'm seeing on each side:

What can I do to prevent this?

whizbang

can you post a bigger pic.. the front of the house maybe.

10-10-20

Yes, a wider photo is needed alright.

Also what type of render is that, is it monocouche / k-rend? What's the age of the house?

alinois

The white render is monocouche. House is about 3 years old. Here is a picture of the front door with the two areas I mentioned marked in red:

hydrus21

I would say that having a step free access has bridged the damp-course.

10-10-20

https://www.boards.ie/discussion/comment/122910225#Comment_122910225

It's a very distinctive mark, almost like a tide-line, and it abaits and points right at the drain where there is no occurrence of sand to wick the moisture upwards.

Bullocks

The ramp is probably bridging the damp course .

It would be worth checking that the aco drain is draining away properly aswell and holding water that's leaking out either side and soaking up the wall , you'd be surprised how many aco drains are put in across doorways and not piped anywhere

alinois

There is some sand between the floor blocks and between the wall and the floor blocks.

I also checked and the aco drain does connect to a drain pipe and drain the water properly.

If the floor is bridging the damp-course, what should I do?

hydrus21

A vertical DPC in that area. Old method would be a cement plinth with roof slate bedded in.

alinois

https://www.boards.ie/discussion/comment/122912096#Comment_122912096

By vertical DPC do you mean, removing the floor blocks and paint something like this on the wall, then put the block back on?

Or something more complex?

hydrus21

More complex. ( Sorry )

You need a waterproof vertical barrier ( slate) starting just below

your DPC and finishing 150mm above the raised ground level. Another option is to remove the perimeter blocks

and soil to below DPC and fill with gravel to match existing.

The last option is a compromise but if the area is sheltered from the weather, it should be ok.

hydrus21

I should add, the vertical slate method is for exposed brickface which you don't have, so a plinth 150mm above ground level in your case is not nescessary. I'm not familiar with modern waterproof paint products but the one in your link is for internal use.

alinois

https://www.boards.ie/discussion/comment/122915942#Comment_122915942

If I add a vertical slate, are you suggesting that should be add on top of the monocouche, or should the monocouche be carved to fit in the slate, so it looks like a plinth almost?

GreeBo

I would agree on the DPC being breached by the ramp.

I'd take out the pavers that are against the wall for a few weeks and see if it dries up at all, also agreed on opening up the ACO to make sure its not just draining into the render