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Damp Black Spot patches

Postby Davey M » Mon Mar 10, 2008 10:52 pm

Apologies if this sounds simple to rectify, but i really have no idea!
I recently purchased a property, 2 bedroom ground floor flat that was built approximately 1970.
I have noticed that under the front window, approximately 1 foot from the skirting board and 3 foot in diameter, there appear to be black spots of mould.
This problem also occurs in the back bedroom that runs off the main room above. However the problem in the bedroom is on the adjoining wall to next door (Think this could adjoin with their bathroom?)
The spots in the bedroom are again contained within an area from the skirting board, raising up approximately 2 foot and spread over about 2 foot. The lady in my property does have a canvass type lean-to wardrobe that covers the area.
I am not sure of any airbricks although i will be checking this.
I bought the property in November 2007 and had a full building survey that indicated no damp problems.
So i am just wondering, after reading many of the related topics, if in fact this "black-spotting" could just be because of poor ventilation and a simple spray, like one previously mentioned HG mould spray, would do the trick? or could it be something more sinister?

The lady leaves the heating on constantly so the room is always at a 70 degree temperature (controlled by thermostat).

Can anyone please give advice or their thoughts?

many thanks in advance.
Davey M
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Simply Build It

Postby ALDA » Tue Mar 11, 2008 7:00 pm


It doesnt seem to me that you have a sinister problem!

I do think you may just need increased ventilation!

Constant heat and a moist atmosphere with little ventilation, will encourage mould growth on the colder spots of wall surfaces.
(front room under window)

Unwaterproofed canvass is noted for mould growth and so, if it is touching the wall may be transferring mould to wall!

All furniture should be kept a reasonable distance from walls in any case, so providing ample ventilation behind.

You could try tip I have posted before in answer to damp problems to assess wether you may have a more sinister problem. (I doubt it).

Look at my posts!

Yes apply the product to over come mould growth but do advise tennant in a subtle way to open her windows occasionally and move furniture a couple of inches away from walls.


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Postby Davey M » Tue Mar 11, 2008 10:40 pm

Thanks for your prompt reply.
I shall administer the spray and advise on the preventative measures that need to be taken.

Much appreciated.
Davey M
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