sweetheart wrote:
On Sunday, October 1, 2017 at 2:11:02 PM UTC+1, Jeff Layman wrote:
On 01/10/17 08:54, sweetheart wrote:


As others have pointed out, and your use of inverted commas suggests,
it's a widespread problem outside Cornwall.

The usual explanation is hermetically sealed homes, but I have my
doubts. You've noted that even insulated walls can get condensation
on them, and that north walls are somewhat worse. My infrared
thermometer shows that a north wall, even if insulated, is often a
couple of degrees colder than a south wall (maybe 17 degrees
compared to 19). But should this make a difference?

We have noticed that the bedroom has noticeably more mould than other
rooms (including the bathroom), and even mould (green, rather than
black) appears particularly on leather items even though they've been
stored in sealed in polythene bags for ages. There is no doubt that a
dehumidifier helps, and so far it's the only thing which does.

I can't understand this idea of "leaving a window open" to ventilate
a room, particularly at night. If you have a humidity meter outside,
it almost never fails to reach 95%+ humidity, in the early hours,
whereas inside it will usually be 60 - 70%. So by opening a window,
you are allowing damper air to enter!

Of course, many years ago, in the 40s and 50s, mould never seemed to
be a great problem, Well, there was little if no central heating for
the masses, and people did sleep with windows open, and in winter
ice formed from the condensation inside bedroom windows. But why
wasn't there all this mould we are seeing today? I think the
explanation is straightforward, and is the same reason why gardeners
had less trouble with varieties of roses which were known to be
susceptible to black spot, rust, mildew, and other fungal diseases.
It's simply that the air was polluted with pretty high levels of
sulphur dioxide from all the coal burning fires, and it not only got
mould off the roses, but out of houses too.

In cleaning up the air we breath, we've just exchanged one form of
air pollution for another, except this time it's fungal rather than
chemical. Years ago, after a child had recovered from one of the
common respiratory infections, it was usual to burn a sulphur candle
in the bedroom to fumigate it. It would be interesting to try one
now in a room with a severe mould problem to see if it helped.
Unfortunately, because sulphur candles were effective, they have
been deemed unsafe and it is now impossible to get them easily, if
at all, at a sensible price. Oh, here come the D-I-Y bit - you could
always try making your own!

--

Jeff

Those are interesting observations and since I was a kid in the
1960's I would also think valid. I cannot recall my parents,
grandparents or any of my aunts and uncles having issues in their
cold , often icy in winter , homes.

Sulpher...... I am just wondering now. 'Tis true they have banned
the most effective cleaners and products that kill mold. Nothing
works. Bleach is about the best now.

Just the one comment.
Cheap bleach is rubbish, Domestos is the dog's tasty bits.