Does a vent improve or make condensation worse?

[Dazzy50]

Hi all,

I've searched for similar topics in the forum to get a general idea of what I think I should be doing.

We have what I am pretty sure is a condensation problem in the small bedroom upstairs.

This is a corner box bedroom so has two external walls. The house is a 1930s semi detatched.

The furthest external corner of the room (in photo) and the adjacent wall have mould growth and are often moist.

There is no adjacent pipework which could be leaking. Nor is there any observable leak in the guttering in that corner of the house and no patches of damp indicated by the brick work outside so this leads me to believe it's condensation rather than a leak or damp through the wall.

I am considering installing an air vent by drilling out a couple of bricks but I've seen some conflicting information.

Is this likely to improve the situation or make it worse?
Does warm, moist air leave the house through these vents or does it just lower the room temperature and allow moisture to come IN then condense?

What type of vents are best? Air bricks? Just a grill covering the inside and outside?

Any help greatly appreciated thanks.

 

[endecotp]

You need ventilation at the source of the moisture, I.e. bathroom, kitchen, wherever you dry clothes etc.

The condensation is happening there probably because it is a cold spot.

 

[endecotp]

Though honestly, the amount of mould there is not very much. Just clean it up.

 

[footprints]

I have been trying Wallrock thermal liner in my en-suite so far it seems to be doing the trick, room is much warmer too.
Pricey but seems worth it.

http://www.erfurtmav.com/erfurt-mav-wallpaper-products/wallrock/wallrock-thermal-liner

 

[Dazzy50]

So if I was to put a vent in that room it would make it colder and therefore worse I take it?

And even though the bathroom and kitchen are far away from that room (bathroom opposite end of house) it will still be contributing to the condensation? Bathroom isn't vented but Windows are always open during showers etc.

No it doesn't look like much but it's because I frequently clean it. That is only about a weeks worth.

Thanks.

 

[Dazzy50]

Footprints thanks for the link. Do you find it helps prevent condensation as well as insulate the room?

 

[footprints]

Yes we had a patch on condensation on the outside wall next to the toilet which sits back in a recess despite having an extractor on when using the shower. We did all the outside walls and certainly seems to have stopped it, my son in law used it in a bedroom that had condensation on one wall and it cleared that up too.
Worth getting a roll and doing both walls into the corner, it is a bit like a polyester fabric on the back MUST use the proper adhesive though, just as a guide I found a 5kg tub did about two 75cm wide rolls. You can get other widths if you require.

 

[endecotp]

Moisture will condense wherever is coldest. Improve the insulation in that corner and it will go somewhere else. You need to remove the moisture at source.

 

[footprints]

Moisture will condense wherever is coldest. Improve the insulation in that corner and it will go somewhere else. You need to remove the moisture at source.

Good point worth noting that you still need ventilation to remove moisture from the house, opening a window a tad in bedrooms overnight or for an hour or so in the morning will help a great deal.

 

[Dazzy50]

Thanks for the advice both much appreciated.