I am considering building a shower in a bathroom. I have looked at fitting
instructions and they all seem to rely upon the use of silicone sealant to
make them watertight. But there is an abundance of complaints from people
saying that in their shower the silicone is covered in thick, black mould.



Is mould in a shower unavoidable, or is there something that I can do in
construction or maintenance to guarantee there will never be any mould
growth on the silicone sealer?



I have not had any experience of dealing with silicone sealant in a shower
enclosure and would like to know what I can expect.

Sal wrote:

Is mould in a shower unavoidable, or is there something that I can do in
construction or maintenance to guarantee there will never be any mould
growth on the silicone sealer?

Firstly, choose a good sealant incorporating mould inhibitor.

The only way to avoid mould growth, it to ensure that the sealant
does not stay wet. Wiping down after use, coupled with adequate
ventilation of the area, are both essential.

There are also mould inhibitor sprays which are pretty good as an
additional preventative measure.

To recap, if you repeatedly allow moisture to remain in contact
with the sealant for significant time, then mould is practically
inevitable.

Chris
--
Chris J Dixon Nottingham UK


Have dancing shoes, will ceilidh.

Sal wrote:

Is mould in a shower unavoidable, or is there something that I can do in
construction or maintenance to guarantee there will never be any mould
growth on the silicone sealer?

If it stays wet, then mould is inevitable, IME even in the stuff
allegedly containing inhibitor.

I had a shower which was extremely prone to mould, but changed the
bathroom extractor fan to a humidistat-controlled one. Result - nice
dry bathroom and no mould regrowth.

David

"Lobster" wrote in message
news
Sal wrote:

Is mould in a shower unavoidable, or is there something that I can do in
construction or maintenance to guarantee there will never be any mould
growth on the silicone sealer?

If it stays wet, then mould is inevitable, IME even in the stuff allegedly
containing inhibitor.

I had a shower which was extremely prone to mould, but changed the
bathroom extractor fan to a humidistat-controlled one. Result - nice dry
bathroom and no mould regrowth.

David

David and Chris are right. Keep it dry by wiping down after showering. A
micropore cloth is very good for that.

Mary

On Sun, 14 Jan 2007 17:28:23 -0000, "Mary Fisher"
wrote:



David and Chris are right. Keep it dry by wiping down after showering. A
micropore cloth is very good for that.

Mary


Agreed but can I just add ' gently ' because it can also be pulled out.

Andy

"Andy Cap" wrote in message
...
On Sun, 14 Jan 2007 17:28:23 -0000, "Mary Fisher"

wrote:



David and Chris are right. Keep it dry by wiping down after showering. A
micropore cloth is very good for that.

Mary


Agreed but can I just add ' gently ' because it can also be pulled out.

?

If that's so why do people have such a problem when they try to remove it?

Mary

Andy

On Mon, 15 Jan 2007 10:28:20 -0000, "Mary Fisher"
wrote:



If that's so why do people have such a problem when they try to remove it?


Because I'm not suggesting it rips it out completely but damages it.

My wife is a particular stickler for looking after the bathroom and after many
years, there really is hardly any noticeable deterioration, all down to her, oh
and of course the care with which is was first installed ! ;-)

Andy

On Sun, 14 Jan 2007 12:52:24 -0000, Sal wrote:

Is mould in a shower unavoidable,

It's more like mould in silicone sealer is inevitable. The sealer contains
acetate, a by product of the curing process, which is very tasty to mould,
in laboratories moulds are often cultured in an acetate solution.

One solution is to use a more expensive sealant. However these are also not
without their problems. I use "Evostick Nail and Seal" for many jobs. It's
far superior to silicone since it is a sealant designed for use below the
waterline in boats immersed in salt water. It does not support the growth
of mould. Sadly if used where it can be seen, it has the unfortunate
characteristic of yellowing with age.

An alternative is to use a polyurethane sealant such as Sikaflex which is
also resistant to moulds.

Thank you all for the information. Keeping the silicone sealant dry seems to
be important.
I am not sure why the silicone sealant used in window frames never seems to
get mouldy: it is often very wet for long periods in rainy weather.

Steve, your suggestion to use materials other than silicone sealant is
interesting. If the choice was between a yellowing seal or a mouldy seal, I
should be happy with the yellowing one.
What do the phrases "does not support the growth of mould" and "resistant
to moulds" mean? Do they mean you will never see mould on such surfaces?

Regards
Sal.

On Sun, 14 Jan 2007 23:26:38 -0000, Sal wrote:

What do the phrases "does not support the growth of mould" and "resistant
to moulds" mean? Do they mean you will never see mould on such surfaces?

"Does not support the growth of mould" means there's no acetate in the
sealant, acetate is the growth medium for mould.

"resistant to moulds" means that unlike silicone, mould doesn't grow in the
body of the sealant. If you look at mouldy silicone you will find it
impossible to clean off the mould because it penetrates into the sealant.
Hence rubbing at the surface will not clean it. With the Evostick
co-polymer sealant and tiwh Sikaflex mould may form on the surface in damp
conditions but it can be wiped off with a cloth.

Steve Firth wrote:
On Sun, 14 Jan 2007 12:52:24 -0000, Sal wrote:

Is mould in a shower unavoidable,

It's more like mould in silicone sealer is inevitable. The sealer contains
acetate, a by product of the curing process, which is very tasty to mould,
in laboratories moulds are often cultured in an acetate solution.

One solution is to use a more expensive sealant. However these are also not
without their problems. I use "Evostick Nail and Seal" for many jobs. It's
far superior to silicone since it is a sealant designed for use below the
waterline in boats immersed in salt water. It does not support the growth
of mould. Sadly if used where it can be seen, it has the unfortunate
characteristic of yellowing with age.

An alternative is to use a polyurethane sealant such as Sikaflex which is
also resistant to moulds.

Has anyone tried this stuff?
http://www.screwfix.com/app/sfd/cat/...66293&ts=48272
"Guaranteed to stop black mould for 10 years."

"Martin Pentreath" wrote in message
ups.com...
Steve Firth wrote:
On Sun, 14 Jan 2007 12:52:24 -0000, Sal wrote:

Is mould in a shower unavoidable,

It's more like mould in silicone sealer is inevitable. The sealer
contains
acetate, a by product of the curing process, which is very tasty to
mould,
in laboratories moulds are often cultured in an acetate solution.

One solution is to use a more expensive sealant. However these are also
not
without their problems. I use "Evostick Nail and Seal" for many jobs.
It's
far superior to silicone since it is a sealant designed for use below the
waterline in boats immersed in salt water. It does not support the growth
of mould. Sadly if used where it can be seen, it has the unfortunate
characteristic of yellowing with age.

An alternative is to use a polyurethane sealant such as Sikaflex which is
also resistant to moulds.

Has anyone tried this stuff?
http://www.screwfix.com/app/sfd/cat/...66293&ts=48272
"Guaranteed to stop black mould for 10 years."


In my experience these year markings are like wris****ch water depth
markings (25m = splashproof, 50m swim, 100m dive underwater).

I find dividing them by 5 works OK:

Guaranteed 10 years ; you might get 2 years without mould.
etc.

I use the "guaranteed 35year" ones from the sheds, in the hope they might
last 7.


--
Bob Mannix
(anti-spam is as easy as 1-2-3 - not)

Bob Mannix wrote:

I use the "guaranteed 35year" ones from the sheds, in the hope they might
last 7.

I'm guessing that you are joking? There's not much chance of my house
being standing in 35 years, never mind the shower that the sealant is
attached to! Anyway, I shall be past caring about mould by then.

"Sal" wrote in message
...
I am considering building a shower in a bathroom. I have looked at fitting
instructions and they all seem to rely upon the use of silicone sealant to
make them watertight. But there is an abundance of complaints from people
saying that in their shower the silicone is covered in thick, black mould.

Is mould in a shower unavoidable, or is there something that I can do in
construction or maintenance to guarantee there will never be any mould
growth on the silicone sealer?

1. Use expensive sealant with fungicide (eg Corning 785).
2. Install decent fan to ensure proper ventilation of shower area. I fitted
a £30 humidistat controlled fan, waste of time as it had no temperature
compensation so in winter would either come on by itself when cold or be
triggered by the shower and never turn off. A £120 Ventaxia (?) humidity
controlled temperature compensated fan cured that.
3. Use a water softener. Since fitting a water softener not seen any mould
growth in both my showers, despite poor ventilation in one, which did suffer
mould issues.