Damp wall/sealant.

[Rainman4707]

External wall of my house is rendered. I think my wall has either condensation or mould.

I have been advised to keep this wall waterproof to stop damp getting in.

So I've contacted a painter who said he will use waterproof paint & a sealant. I read on a DIY site that you shouldn't use a sealant because if you have moisture in the wall & the internal face of the wall has condensation or mould, applying a sealant on the external face will seal the damp IN.

Any advice? I'm tempted to instruct him to just use the paint, not a sealant.

 

[Bible_Belt]

If you have a water leak, there are larger issues that need to be addressed. Maybe it is the roof. Water will move inside a roof or wall, so the place you see it is not necessarily where it is entering the home. All construction types are different, but I have never seen a water leak fixed correctly with paint.

 

[speed dawg]

External wall of my house is rendered. I think my wall has either condensation or mould.

I have been advised to keep this wall waterproof to stop damp getting in.

So I've contacted a painter who said he will use waterproof paint & a sealant. I read on a DIY site that you shouldn't use a sealant because if you have moisture in the wall & the internal face of the wall has condensation or mould, applying a sealant on the external face will seal the damp IN.

Any advice? I'm tempted to instruct him to just use the paint, not a sealant.

You need to figure out how the water is getting in. I do this sort of thing all the time. Need more details.

Even if it's an underground wall where seepage is getting to it - paint will only temporarily fix this issue. Eventually the paint will degrade and the water will get in again.

 

[Rainman4707]

Thanks for replys.

I know that i obviously need to find out what the problem is, so i'm going to apply waterproof paint, install vents incase it's a condensation problem. I am also going to get new gutters. Those things I will do first.

My main question at the moment is....my painter is going to use a sealant before he applys waterproof paint. Should I allow him to do this or should I just tell him i'm afraid sealant will stop any moisture/condensation/damp getting out if he applys sealant, so just use the paint??

 

[speed dawg]

Thanks for replys.

I know that i obviously need to find out what the problem is, so i'm going to apply waterproof paint, install vents incase it's a condensation problem. I am also going to get new gutters. Those things I will do first.

My main question at the moment is....my painter is going to use a sealant before he applys waterproof paint. Should I allow him to do this or should I just tell him i'm afraid sealant will stop any moisture/condensation/damp getting out if he applys sealant, so just use the paint??

For the second time, don't do a damn thing until you find out where the water is coming from. And no, you should not paint OR seal over a wet wall. What type of wall? Above ground? Under ground?

1) Do you live on a hill?
2) Do you have negative pitch back toward your house?
3) Any reason why ground water would seep towards your house?

Pictures would help too. I could probably diagnose this pretty quickly.

If it's typical seepage, an underdrain system is the best thing you can do. You mention gutters - have you ever watched the area during a storm? Is water spilling over?

 

[Rainman4707]

For the second time, don't do a damn thing until you find out where the water is coming from. And no, you should not paint OR seal over a wet wall. What type of wall? Above ground? Under ground?

1) Do you live on a hill?
2) Do you have negative pitch back toward your house?
3) Any reason why ground water would seep towards your house?

Pictures would help too. I could probably diagnose this pretty quickly.

If it's typical seepage, an underdrain system is the best thing you can do. You mention gutters - have you ever watched the area during a storm? Is water spilling over?

The wall we are discussing is rendered.

The property stands on a slightly sloping site with a front garden and rear yard & no negative pitch back.

The property is situated in a former mining area. I had a mining report done & no problems were found. Some locals do believe there might be water running underneath the houses in our street due to the former mines.

Yes I have watched the gutters & there were a couple holes where water was dripping down, I fixed these, but now there are another couple of holes. The main reason I want new gutters is because my neighbour has big bundles of grass hanging over his gutters that he hasn't cleaned, so they are dripping loads of water down his wall. I'm going to find someone to do the work on both our gutters. Hopefully he is fine with this.