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Damp Proofing Question
How to get rid of black mould?
Hi I have noticed black mould all over my house in the past 2months. It is more prominent in the hall and living room. I have a young daughter with asthma. I washed the Walls down with bleach but it has returned. Any advice would be appreciated
Hi , The cause of black mould is generally condensation caused by increased humidity temperature , this forms water droplets on cold surfaces and around windows . excessive moisture can be eliminated by installing passifyer vents as these remove a higher content of internal moisture (approx 2.3 litres per 24hr)
as they are filtered they do not allow cold air back in , Look them up on the internet to familiarise yourself with them.
A mould killer solution is more affective than bleach as black mould is a sterile growth. when decorating use emulsion with an anti mould additive mixed in ,
Answered 11th Jan 2013
You should start by sorting the cause of the damp .Check air bricks ,vents are open working .ensure all guttering on exterior is working then look at outside walls for signs of green moss or algae.when the cause is sorted then clean with bleach and re decorate.
Answered 9th Jan 2013
Where you say its more prominent in the hallway this could be due to the door being left open from your kitchen or bathroom the steam goes on to the walls then turns to mould always keep these doors closed when used and if possible leave a window open, it is usually out side walls that are affected
also do not dry clothes on radiators this also gives out more moisture which is feeding the mould,just try to keep these areas free from any moisture to try and manage to damp,
Answered 11th Jan 2013
Condensation accounts for approximately 70% of reported domestic damp and can commonly be attributed to a lack of balance between heating and ventilation resulting in a rise in relative humidity. Air can hold more water vapour when warm than when cold. When warm air is cooled, such as when the heating system is switched off at night, it will deposit the water that it can no longer retain as condensation on a cold surface.
A similar effect that can be demonstrated by breathing onto a mirror or other cool surfaces. In its less serious form, condensation may “steam up” windows and mirrors.
In more severe cases, it can be absorbed by surface wall finishes and underlying plaster causing dampness although the underlying brickwork or masonry will normally be of a lower moisture content. It may cause mildew on fabrics and leather and, in extreme cases, can cause walls to be visibly wet. It is frequently accompanied by mould growth, of which the most common is “black spot” – a mould which appears first as small soot-like spots, and which can join up and cause large black areas. Condensation may occur at any height on almost any cool surface.
Condensation damp permits fungal growth. Materials such as wood, paper, wallboard, ceiling tiles, furnishing fabrics and even masonry and plaster can provide nutrients sufficient for mould growth providing the controlling factor is present i.e. the availability of sufficient moisture.
Are your kitchen and bathroom areas adequately ventilated ?? Is your property solid or cavity construction?
Answered 13th Jan 2013