Persistent Dampness in bedroom corner

[kitkopool]

Hello DIY enthusiasts,

I need some advice regarding a recurring dampness problem in my son's room. The 90-degree corner near the window is always damp, likely due to the lift section behind the wall. Despite multiple repaints using basic stain stop paint, I'm still battling black dirt and mold.

I'm looking for more effective solutions to address this dampness and prevent mold from seeping through the walls. If you've encountered a similar issue or have expertise in dealing with dampness problems, I'd greatly appreciate your input.

Thank you for your help,

kitkopool

 

[Trazor]

Have you tried this...........

Zinsser Bulls Eye 1-2-3 Primer-Sealer White 1Ltr - Screwfix

Order online at Screwfix.com. Interior and exterior, water-based, primer / sealer. Adheres to all surfaces without sanding. Blocks stains, permanently sealing graffiti, grease spots, tar and asphalt, indoors and out. Low odour application and conveniently quick-drying with excellent adhesion to...

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Worked superbly for me, for a similar problem.

 

[securespark]

Ground floor, first floor?

I have similar issues.

Start by checking basic things like guttering, loose or missing render or pointing and problems with lead flashings. You will probably need a ladder/ scaffold or drone to get up and have a look.
Also make sure that window frames are properly sealed up.

 

[kitkopool]

I live on the building's fourth floor, which is the topmost level. Unfortunately, I don't have access to the building's roof due to it being under shared ownership. Permission to access the roof hasn't been granted, primarily due to security concerns and related factors.

The part of the room affected by dampness is positioned near the windows, which remain partially open most of the time. These windows have an older design with horizontal glass inserts, allowing a specific angle of airflow to enter. I believe this continuous influx of air might contribute to the issue.

I hope my explanation clarifies the situation. Thank you for your understanding.

 

[kitkopool]

https://www.polycell.co.uk/product/polycell-one-coat-stain-stop/


I used a product last year that seemed to work, but unfortunately, it only kept the dampness at bay for about three months.

Now, I'm considering a different approach. I plan to sand down the affected area using my electric sander to remove any dirt or residue. After that, I intend to apply the solution from the link mentioned above.

Do you think this method will be more effective than using the STOP STAIN COAT product?

 

[securespark]

I assume you live on the top floor of a low rise block of flats, then?

Is the roof flat?

What direction does/ do the affected wall(s) face?

What is the condition of the render or pointing?

You may not be able to use access equipment, but if you know anyone with a drone that could go up there and video the building, that should give you some clues.

Do you pay monthly or annual maintenance fees and s there a management committee?

If the leaks are due to a failure in the shared structures of the building, IE window frames, masonry and guttering/ pipework, you should be able to get that looked at by the management committee?

As far as ventilating rooms go, that is usually a good thing, providing rain is not entering the building.

 

[JohnD]

The shape of the damp looks to me like water ingress from above, like a defective roof or gutter.

Opening a window does not cause condensation.

To find out, tape a piece of clear plastic or clingfilm tightly to the wall. If water forms behind it, the water is coming from the wall. If water forms on the room side, it is condensation from humidity in the room, such as a kettle or heated fishtank in that corner.

 

[kitkopool]

The problem primarily arises during winter or extremely cold days. I notice numerous water bubbles forming on the wall along with the accumulation of dirt and mold.

Upon checking the wall just now, I found it to be dry. While not completely perfect, it's not as wet as it tends to be during the winter.

I apologize for providing such a detailed description, but I believe it's crucial to emphasize these specifics in order to identify the best solutions.

 

[foxhole]

Ceiling most likely has a lack of insulation and or a leak from flat roof. Ventilation prevents mould spores settling .Do you dry washing in the property?

 

[kitkopool]

Have you tried this...........

Zinsser Bulls Eye 1-2-3 Primer-Sealer White 1Ltr - Screwfix

Order online at Screwfix.com. Interior and exterior, water-based, primer / sealer. Adheres to all surfaces without sanding. Blocks stains, permanently sealing graffiti, grease spots, tar and asphalt, indoors and out. Low odour application and conveniently quick-drying with excellent adhesion to...

www.screwfix.com

Worked superbly for me, for a similar problem.

you reckon I should try it ?

 

[Wayners]

Cavity cameras are cheap to have a look in the wall but you maybe better to go down official lines.

It's a cold spot or there is water getting in behind. Get it investigated.

Painting over will not fix that