Damp Proofing Question

Mould appearing on walls

I live in a 1950's ex council house. It is of good solid construction with cavity walls as you would expect. Some years ago we had a company come round and pump in insulation into the cavities and lay extra insulation in the loft. Since then we have noticed mould appearing on the walls in one of the bedrooms. It has reappeared after redecoration. There is also an air brick that had been plastered over at some point in the past. Should I open up the air brick or have I got a more serious problem.

2 Answers

If it small spores black mould, chances are this is a condensation problem. More noticeable in the winter months due to having the heating on.

Warm air hitting the cold surface of the outside wall causes the condensation to form which causes a warm damp environment for the mould to grow.

Opening the air brick may well help but try and open the windows for a time first thing in the morning to air the room or open the night vents ( if any ) in the windows

Other than this a cheap fungicidal wash from b&q will keep it at bay for a while.

This is a prevention rather than cure situation.

Hope this is of some help


P.s there are companies out there that will supply and fit a ventilation system for the whole house but it is expensive rather than costing a few pounds twice a year for the funny wash

Answered 29th Jan 2012

cms joinery

Member since 20 Nov 2009

You need ventilation and a good air flow, unblock the air vent and install extra vents if needed.
If you havent got trickle vents above the windows, these can be retro fitted.

Answered 29th Jan 2012


Member since 29 Oct 2008

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