Page 1 of 1
Why do I Have this Damp Patch when the Temperature Drops?
Posted: Sun Nov 29, 2015 10:47 am
by Ashers
I have a damp patch that comes and goes in the corner of my bedroom. The patch does not appear in the summer or when we have warm rain.
However as soon as the temperature drops outside the patch reappears. The patch mainly appears overnight and disappears again during the day as temperatures increase.
What is causing this and how do I remove it?
Re: Why do I Have this Damp Patch when the Temperature Drops?
Posted: Tue Dec 22, 2015 11:59 am
by thedoctor
The damp patch is more likely to be condensation than a leak. It appears when the walls are colder because the warm air is hitting a cold surface and condensing. See our project page on condensation here
https://www.diydoctor.org.uk/projects/condensation.htm When the walls warm, the air does not condense. Bingo - no mark.
Ventilation required to stop this happening
Re: Why do I Have this Damp Patch when the Temperature Drops?
Posted: Sat Dec 26, 2015 8:09 pm
by Ashers
Based on that should the insulation above be in the gap between the wall and wooden rafter.
Re: Why do I Have this Damp Patch when the Temperature Drops?
Posted: Sun Dec 27, 2015 11:04 am
by Ashers
Based on the above post, should there be insulation between the wall in the attic (attached to next door) and the wooden beam or is this leading to the poor ventilation.