DIY Doctor UK DIY Forums

Hi,

I live in what I believe is a 1920's house / maisonette which has some kind of damp.

The area in a corner in the bedroom is not enclosed, so I think it has reasonable ventilation. If my html is working there should be a picture just after this:



It seem to get bad in the winter and then in the summer i'll have a go at fixing it. I've tried the following:

Damp proof paint inside
Damp proof paint out side up to about 10 inches from the floor.

Checking the outside drain pipes for leaks/blockages, including up on the roof. Here's a piccy of the drain just outside exactly opposite the right hand corner in the first image. I'm not sure if the image will be in the right orientation, but the black drainpipe is vertical and on the left of picture if viewed correctly.



The pipe did have a brackett made of wood that penetrated into the brickwork via long screws, but I've removed the brackett and plugged the holes with the white sillicone

I've been outside when it's raining to look and the drains seem to function normally with no leaks. Here's the drain looking up from the ground



Just above the damp is a wood frame single pane window which can be seen here:



I've sealed all around the edges with sillicone sealant.

Just below the window, and again on the same wall as the damp is this brickwork. While we're at it, I'd like to know, how do I tell if I have solid walls. People have mentioned about footer and headers, but I'm not clear on it:




Immediately above the corner there is a suspicious looking area next to the ceilling. This corner is directly above the damp:



The flat upstairs is inaccessible, so I can't show you any pictures of the room above.

So, the big question is, what's causing my damp, and how can I fix it?


All the best,

Jenny

I would remove the skirting board,check if its damp behind.If it is its rising damp.
the damp on the coving could be leaking in from the parapet wall flashing into the builing,but its hard to see from the pictures..

Thanks for helping a girl out Brickie!

welsh brickie wrote:I would remove the skirting board,check if its damp behind.If it is its rising damp. .

I've removed most of the skirting, there's a bit left in but i can get behind it to touch the wall. The back of the skirting board was not wet or rotten.






When I touch the wall below where the skirting board was, my hand comes away with dust on it, but I wouldn't sat they that there was any moisture there. I know in the picture some of the plaster might look wet but it's kinda grey in colour in some places. The plaster is loose ish, but i don't know if thats because of the beating i gave it to get the skirting out, it was nailed in with 3 or 4 inch nails

I then removed some lining paper as can be seen in this picture. The picture should be with the green paint mark at the top. That mark is just below the wooden window frame.



I kind of imagined that there would be more staining below the lining paper, but the wall looks quite good and again, to touch the wall feels dry.

Is the amount of water from a damp wall something you can see with your eyes or pick up by touch or do you need a damp meter of some kind?

Would you expect to see staining below the lining paper if the damp was coming from inside the wall. Maybe the window could be the culprit?

welsh brickie wrote:the damp on the coving could be leaking in from the parapet wall flashing into the builing,but its hard to see from the pictures..

If you tell me what pictures would help, i'll get up on a ladder and have a go taking them

Many thanks once again!

hi, it looks like penitrating damp from around the window,water will always find the lowest level,So I assume that its been creeping through for a while before the brickwork was repointed.
Tap the wall Im assuming it will sound hollow.If it was me I would remove the plaster thats black and paint the area with bitumin and then replaster.

With regards to the coving problem,Take a hosepipe up the ladder and hose the entire area where you think it may be coming in,and then check for damp.You can use a waterproof paint to seal any areas you think it might get in

welsh brickie wrote:hi, it looks like penitrating damp from around the window,water will always find the lowest level,So I assume that its been creeping through for a while before the brickwork was repointed.
Tap the wall Im assuming it will sound hollow.If it was me I would remove the plaster thats black and paint the area with bitumin and then replaster.

With regards to the coving problem,Take a hosepipe up the ladder and hose the entire area where you think it may be coming in,and then check for damp.You can use a waterproof paint to seal any areas you think it might get in

Hi,

I'm gonna try putting some tissue paper around the window to see if I can catch a leak. I'll get back to you with my findings!

I've replastered with plaserboard quite successfully before, would that work in this situation, or should i go for "proper" plaster? (not so good at this :O)

With the plaster removed you can spray the wall and around the window outside with a hosepipe to see where water is penitrating.
When replastering first seal the wall with a waterproof paint/solution and then dryline the wall.

Hi

I do not believe that this a rising or penetrating damp problem, from the pictures I believe this is just condensation. If you can wipe with a cloth or your hand and it comes away as as sooty type substance, then it is condensation you have, old building can have cold spots as they have no insulation like the more modern homes, try a mildew cleaner spray applied to walls and make sure that that room has plenty natural ventilation and heat, this will normally keep it at bay. The really cold tempertaures outside at present will not help.

If it was rising damp it would appear on the wall above the skrting like a tide mark and coloured like tea colour with penetrating damp then as it sounds it is water that is getting in from the outside, if this was the case the walls would be wet.

Hope this helps

SPUD1701 wrote:Hi

I do not believe that this a rising or penetrating damp problem, from the pictures I believe this is just condensation. If you can wipe with a cloth or your hand and it comes away as as sooty type substance, then it is condensation you have, old building can have cold spots as they have no insulation like the more modern homes, try a mildew cleaner spray applied to walls and make sure that that room has plenty natural ventilation and heat, this will normally keep it at bay. The really cold tempertaures outside at present will not help.

If it was rising damp it would appear on the wall above the skrting like a tide mark and coloured like tea colour with penetrating damp then as it sounds it is water that is getting in from the outside, if this was the case the walls would be wet.

Hope this helps

Hi Spud and Brickie,

Many thanks for helping.


I wiped a tissue on the wall and look a photo:



A few questions / debating points:

The area is in my bedroom, so it's quite warm (2 meters from the radiator).

There is another corner in the room on the same outside wall, that is further from the radiator (4 meters) and with less ventillation and that is ok.

The pattern of the stain does seem to sugguest something running downwards?

Brickie, it's been snowing not raining but so far, nothing is showing up on the tissue I've placed around the windows frame. I've been outside and poured but 5 kettle's worth of water on and around the window frame and all that came through was about 3 tablespoons in the bottom right of the window, so i poured water at that place inside and It sank into a crack in the paint and dissappeared. Here is a photo of the crack outlined in red. During the whole process, nothing has showed up on the tissue paper:



Should i do the soaking with a hose outside I wonder?

Spud, does the tissue paper show what you'd expect from condensation?

Forgot to say, can't hose the area as the hosepipe is frozen!

its difficult to see if its penitrating,rising damp or down to poor ventilation as spud says,
Try cleaning the black area with neat bleach,When it dries paint the area with a pva solution.I think condensation is dripping down the window frame behind the plaster causing the mould.

welsh brickie wrote:its difficult to see if its penitrating,rising damp or down to poor ventilation as spud says,
Try cleaning the black area with neat bleach,When it dries paint the area with a pva solution.I think condensation is dripping down the window frame behind the plaster causing the mould.

Thanks guys,

I'll try the bleach and pva and get back to you if it returns,

Happy Christmas

Hi yes, this looks like condensation, that fact that you could wipe it off suggests the same.

I agree with welsh brickie about the condensation down the windows, from the pictures they appear to be single glazed and probably have no trickle ventilation in them as the modern windows, therefore the normal build up of heat from a bedroom - usually from drying things on radiators, breathing when sleeping can all create these problems.

To keep condensation at bay you usually need heat and natural ventilation.

Older properties sometimes had vents in the walls of the rooms rather than trickle vents in windows, so there may have been something some time ago that has been removed.

If it is possible to open and lock window ie nightlatch I would try this along with heating the room.

As the windows as old maybe just needing reponting/mastic around outside to ensure no water getting in, but the black stuff on cloth is certainately not rising damp.