Mould on Ensuite Bathroom Ceiling (New House)

tbayers

I am living in a newly built house now for the past 18 months. It is in a housing estate so not a once off. Around 6 months ago noticed some black spots of mould appearing on the ceiling just around the edges where the wall and ceiling meet in the bathroom ensuite. We had a painter paint the whole house so didn't think much of it (wasn't sure what paint he used) and stripped the mould from the ceiling with bleach to the point where no paint was left to make sure mold wasn't reaching the pasterboard -  it wasn't, cool. Went onto re paint the ceiling with anti mould paint. However spots have now appeared in a different area with a vengeance and started to gently appear in old area since re painting.
The room is only around 4 metres squared so pretty small and yes it does have an extraction fan and no window. Just before I cleaned the ceiling the first time around the builders were back to (what it seems) install more insulation in the attic so I don't think that is the problem (but maybe should arise suspicions??).
Anyway, apologies for long back story but felt it was required to fully explain. So my questions are: Best way to remove mould properly? And any suggestions to find out what can be causing it? I haven't been up in the attic yet to trace the extractor fan to make sure its actually going somewhere and to see if there are any issues on the other side of the board. Fan is usually left on for a half an hour post shower which is usually used in the evening times. Any advice, comments much appreciated

listermint

tbayers wrote: »

I am living in a newly built house now for the past 18 months. It is in a housing estate so not a once off. Around 6 months ago noticed some black spots of mould appearing on the ceiling just around the edges where the wall and ceiling meet in the bathroom ensuite. We had a painter paint the whole house so didn't think much of it (wasn't sure what paint he used) and stripped the mould from the ceiling with bleach to the point where no paint was left to make sure mold wasn't reaching the pasterboard -  it wasn't, cool. Went onto re paint the ceiling with anti mould paint. However spots have now appeared in a different area with a vengeance and started to gently appear in old area since re painting.
The room is only around 4 metres squared so pretty small and yes it does have an extraction fan and no window. Just before I cleaned the ceiling the first time around the builders were back to (what it seems) install more insulation in the attic so I don't think that is the problem (but maybe should arise suspicions??).
Anyway, apologies for long back story but felt it was required to fully explain. So my questions are: Best way to remove mould properly? And any suggestions to find out what can be causing it? I haven't been up in the attic yet to trace the extractor fan to make sure its actually going somewhere and to see if there are any issues on the other side of the board. Fan is usually left on for a half an hour post shower which is usually used in the evening times. Any advice, comments much appreciated

Water will condense and stick on any cold surface. So if the surfaces of your walls or ceilings are cold i.e draughts or lack of insulation then you will get water condensing damp and then mould.

Realistically the paint does nothing at all its not a fix.

Need to check the ceiling for insulation. Check the fan is properly fitted and that it has a vent tube that is not blocked and exits externally.

Might be a case of more insulation and upgrading the fan and making sure it has a timer to run longer when room is in use.

jonon9

Check to see if the fan is sucking air, use a tissue, next check to see if the fan duct isnt blocked.

How big is your bathroom sometimes a too small a fan in a large bathroom will be insufficient in removing steam quickly.

tbayers

The tissue trick is a good tip, will try that. It's only around 2.5m x 2.5m so pretty small. As I suspected will have to investigate the fan duct and see if its actually working.

jonon9

No an extractor fan sucks not blows there should be no down draft. If your feeling a down draft than the fan was put in wrong or theres something in the vent thats forcing the air back down.

tbayers

If the fan is piped to say the gutters or in that direction what is best way to determine if it is actually blocked? Just go for broke and take it out and put in a new one? COnsidering a new powerful extractor fan but this one should be doing the job, as mentioned its a small room so there is something else going on.

jonon9

tbayers wrote: »

If the fan is piped to say the gutters or in that direction what is best way to determine if it is actually blocked? Just go for broke and take it out and put in a new one? COnsidering a new powerful extractor fan but this one should be doing the job, as mentioned its a small room so there is something else going on.

Depends on how it was vented out, I.E through the roof or through the fascia. Best check everything. Sometimes to save money the cheapest fans are used and personally they dont work. But before thinking about replacing the fan check all avenues.

As for cleaning the mold a pair of rubber gloves, face mask and bleach and scrub the hell out of the ceiling and let dry completely before painting but you must address the steam first.

tbayers

It was questioned during the snag list and they said it comes out the fascia. Cheers for all the tips!

jonon9

tbayers wrote: »

It was questioned during the snag list and they said it comes out the fascia. Cheers for all the tips!

Ok well check everything go into the attic check the vent pipe etc, go outside and look to see if the vent cover isnt blocked of covered. It could simple be the fan itself.

dok_golf

Just a quick question. Is the door to en suits closed or open in general?

tbayers

Generally open I would say. We don't generally have the heat on upstairs due to the very good heat retainment in these new houses

K.Flyer

I have come across many bathroom extractor fans that are not fitted to any tubing or so badly fitted that moisture gathers and causes mould.
I have even found one where the "genius" installer hooked up the flexible pipe to an internal soil stack, so when the wind blew the wrong way the owners were getting blasted with sewer gases.
You need to get into the attic make sure that the tube is connected to the fan and is running level and doesn't look like a roller coaster.
Also its very important to realise that extractor fans will never pull moisture laden air / steam out of a room if the room is relatively air tight, it needs to have a way for air to enter the room either by a gap at the bottom of the door or an open window.

Sleeper12

Most 4 inch fans are for smells and not steam.

You need to make sure that the fan is ducted to the outside of the house.

You need to have another source of air in the bathroom. Without it the fan creates a type of vacuum & can't move air around. This might involve removing an inch or so from the bottom of the door or putting in a vent above the door.

Rule of thumb is power shower goes into the main bathroom because you have a window for air. Power shower pumps out 10 to 20 litres per minute so much more steam. An suit should only have an electric shower or gravity fed shower. The most these produce is 4 litres per minute so much less steam.

I'm betting they installed a 4 inch fan for smells. These cost 15 to 20 euro. Imagine a hoover with little suction & you change it to a more powerful one. Same with the fan. You can get better ones for around 100 euro.

Having said all of that it's still a terrible setup. The room in the house that creates the most steam has no window. I don't know why planning allows this. I would also invest in a dehumidifier for the bedroom. Leave the door open and run in for an hour or so after a shower.

Sleeper12

You need something like this Fan

Even with this I'm betting you'll have a small amount of mould

tbayers

So a small update, went up to the attic to have a look. The piping seems to be perfect and it is going straight out the fascia. That doesn't seem to be the problem. Where the mold is this time is coming from the area where the wall meets the roof in the attic. Obviously isn't a whole lot of insulation there as area is very tight but there is some there. So it is leading me to think that it is indeed the weak fan that is installed. I have attached some pictures. They are of extremely poor quality as the focus is broke on my mobile, go figure! But I think it shows what im dealing with. I also held up a single piece of toilet paper and it just about kept hold of it. It couldn't hold up two pieces of toilet paper

Which leads me onto why I am in here, has anybody any experience changing these fans? From what I could gather up in the attic; first of all its very tight so any work up there would be a major pain. Secondly, it looks like the extractor pipe is fixed on, can these be cut away and re fitted with new pipe? And it looks like its four inch, I had no measuring on me at the time, so would retro fitting a more powerful 4 inch fan work by just replacing fan and using existing pipe diameter?

Sleeper12

AFAIK only a REC can change any electrical fittings in the bathroom. Just throw that out there.

There are two types of fans. Ones that are simple on & off and ones that are timers. If yours is timed then you should get a timed fan. A timed fan has a perm live and on on off one doesn't.

Once you source the correct fan it's only a 20 minute job to swap them. If you engage a REC it shouldn't be a expensive. Little more than a call out

You say that there isn't a lot insulation in the eaves. Don't make the mistake of shoving insulation in there. The attic needs to breathe and it needs air from outside.