how to seal-in and paint over black mould on wooden doors and skirting boards

10 Nov 2015
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United Kingdom
How do i seal in black mould on wooden door and skirting boards?

The wood has a yellow gloss base-paint/undercoat, from i guessing twenty years ago looking at the paint tin[ i inherited the house]. on top of that is 3yo matt white paint.
The black mould is under the white paintwork, but not seemingly under the yellow.
the lodger didnt 'notice' the mould.

In the last 30days, i have washed mould off with sugar soap, and then applied with two different mould killers on diff ocassions, but the mould returns thru the white paintwork.
It will take too long to strip the paint, or heat gun it.
eg the door in the photo is 6ft2 high by 90cm with lots of wood detailing.

My plan:

1. i want to wash the paintwork again with mould killer,
2. then seal in the mould with an oil based primer or gloss.
3. and then paint over that with a) anti-mould paint, or b) external wall paint.

Has anyone done that?
and has that longterm stopped the mould coming thru the paintwork?


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Why is the door mouldy? Must be damp -dry it out to KILL the mould. Then prime with Zinsser BIN. Simple.
Mould doesnt come through paint or from wood, it will sit on any surface where the conditions are right for it. There will be no need at all to paint it several times with gloss and mould paint etc, not on a painted door. Once the room is ventilated and warm again due to living in it, the mould shouldnt re appear, as long as the woodwork is wiped down occasionally when cleaning.
Use something like Krud Kutter, one of the best de greasers on the market. Give a thorough clean and then undercoat and top coat as normal. There wont be any need to seal anything in.


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