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Default White mould on treated timber

On 23 Dec, 20:30, " wrote:
wrote:
On 23 Dec, 15:33, " wrote:
We have a cellar that holds water in our 180yr old house. I've
recently had to replace the bottom 3 stairs and the pantry floor
because the timber had rotted due to the water vapour when the cellar
fills up with water(approx 3 inch of water). Cellar is 7 foot deep and
until recently had no air bricks at all and the timber that rotted had
no doubt been there years so it lasted quite long.


I have installed 2 air bricks and replaced the floor and stairs with
treated(tanalised) timber. I used bitumen paint on the ends of the
timber where they came in contact with the damp masonry. This was
maybe 3 months ago and today I went down in the cellar and was rather
shocked to see that the areas of the timber that had bitumen on are
dripping with water and also there is white mould on certain parts on
the timbers?


Dear Mark
Are you sure it is mould and not fungus (not *mould)or
efflorescence(salt crystals? *If so take a picture and I will have a
look
To get a fungus after 3 months is not likely


Chris
PS
IF itis tanalised and has not been cut it is impervious to decay
c


It looks like light white fluff. Like the kind of mould you see on
food, it wipes off. It's on the surface of both the tanilised and
bitumened timber.- Hide quoted text -

- Show quoted text -


Look at it very closely - perhaps under a 10x lens and determine if
you are looking at a biological mould or fine inorganic salts that
just brush off
Sometimes shining a torch at it shows the fine crystals of
efflorescence and the brushing off makes it "disappear". If it is a
mould there is likely to be a residual material where brushed off onto
the floor. dificult to see in small quantities but try scraping it off
with a knife onto black paper
Either way you do not have decay problem
Cure is to
1) isolate with a dpm off a brick pier
2) introduce such ventilation as to keep ambient mc less than 18/20%

If you do this the odd flooding will not cause decay

If it is tanalised I would not worry at all provided the endgrain is
not cut where it abuts the dpm
Chris