Damp on enterior walls at the bottom! Condensation from heat

[melly90]

My husband and I have bought a 70s bungalow that hasn't been lived in for a approx a year. For the last few weeks we haven't lived in it but we've had the heating on just to keep it ticking over to avoid frozen pipes etc. We moved in on Saturday and turned the thermostat up high to warm the house but even after a day it was still very cold. The following day damp started to rise inside of all the exterior walls. We decided to turn the heating off in case we are creating too much moisture/heat and sure enough the next day the damp has nearly gone and a day after it has completely gone. We haven't had any signs of damp at all until now.

We have a builder coming out who has suggested a damp course, another explanation is that the cavity wall might have gotten damp? Or is it because the house has been unlived in and needs "warming" up slowly??

We really need help and would appreciate any advice!

 

[Blagard]

A 70's Bungalow will (should!) have a DPC so that seems like one builder to avoid!

The property will certainly need "airing" and you need to heat and ventilate it, so I would give it a week or so to settle down before doing anything drastic.

With the very wet weather many properties are getting extreme exposure to wet conditions. If it smells damp you could consider using a dehumidifier for a short while.

 

[Architexeter]

Defo sounds like house just needs warming up and loads of ventilation by the sounds of it. There is moisure in the house somewhere and heating is turning it into vapour but you are not letting it escape. Heat the house up and then ventilate and repeat. If you dont let the vapour escape, it will just want to turn back to liquid and it does this at the coldest points in your house which sounds like the base of your walls. I'd strongly recommend fitting extractors to bathrooms and kitchens.

If you want, get some silca crystal moisture traps and see if it accumalates liquid.

Think insulation, think condensation, think ventilation!

hope that helps.

 

[dishman]

I agree with Architexeter

With it being empty for nearly a year before you arrived it has probably has a lot of moisture and damp thorughout (natural when a building has not been lived in for so long).

The heating is not causing the damp to appear (even though it looks that way). Hot air can carry more moisture than cold. So as you heat the house the damp and moisture evapourate. But as Architexeter said, without ventillation, it reaches a saturation point or just has no circulation, has no where to go, and the damp then gets concentrated on to specific cold areas in the house, hence you see it low down on external walls.

So you need to heat your house well, and ventillate a lot for a while until you get it under control. Keep windows open, or if your upvc has it.... night vent where it is locked but open a crack, a bit more secure for a bungalow too.

This is one of the few times I would say maybe use a dehumidifier to aid in reducing the damp inherant in a building that has been empty for a long time. But, do not use it as a long term solution, as this should be a temporary issue....maybe borrow one....

If you still have damp problems after this, then look at how you use the house. For example you need to look at having extractors in your bathroom and kitchen etc. to ensure the house is properly ventillated...

Do not jump in looking for quick fix (that usually have nothing to do with the cause) but costly solutions, when most of the time, it is things that you can change in the house (or how you use the house) that will fix the issue.