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Hi all, hope you can give me some advice.

I live in a house which has been converted into two flats, basically upstairs and downstairs. Before we moved in the landlord gutted the whole flat spending thousands sorting it out. There were damp issues etc. We have had no problems up until now, about 10 months in. We seem to be getting condensation on one small wall in the extension at the back. Everywhere else is fine.

A full damp proof course was installed by a registered company. They have been out and confirmed that the dpc is working fine and that it is a condensation problem.

I have tried dehumidifier which helps but is obviously not a long term solution. The whole house has brand new double glazing with trickle vents (which are open at all times for ventilation). There is an extractor fan in the bathroom and we are having no problems in there.

There is a cooker extractor in the kitchen and we open the window when we are cooking which erradicates most of the steam but obviously not all. The kitchen is located next to the extension and there is no door in between.

We have central heating which is on most of the time apart from during the day if we are at work and during the night. We have no thermostat though, would it be an idea to have one fitted and leave the CH on low in the day? There is adequate ventilation via trickle vents and window locks etc. But we seem to still be having this problem with the one wall in the extension. I am worried that it will gradually start to move its way round the extension if it is not sorted.

Our landlord is on holiday at the moment but is coming on the 9th Jan (he is a quantity surveyor in London so I am hoping that he will understand the problem and resolve it asap).

Any advice/recommendations will be greatly appreciated.

Thanks Elliott111

Trickle vents are a good idea, that doesn't work!
The effect of a trickle vent is based on a passing wind causing a suction that pulls air, warm moist air you have paid good money to heat, from the home and replacing it with cold dry air, that you then pay to heat only to be dragged outside etc; etc; etc.
The height and exposure of a trickle vent has a great effect on the result, in the middle of London at ground level, possibly OK, by the coast or high up expensive.
You have a situation, where warm moist air from the kitchen, is attracted to the nearest cold surface, as heat is always attracted to cold, that surface is your cold wall.
The solution fit a door, or insulate the wall, or warm the wall, by passing warm air across it to raise the temperature, then the moist air will probably condense on a window.
One problem we have these days is, modern double glazed windows are frequently warmer, than the walls of our homes.
Buy a infrared remote temperature gauge from Maplin, or someone, and test the walls. Use it like a spray gun, you will be surprised what you see.
Perry

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