Builders plan to move extractor fan outlet: are they right?

[mutterphore]

So I've waited 8 months and counting for a leaking shower tray to be taken out and repairs to all areas of resultant damp plus new shower room installed....still waiting as there's more than enough work for all the good builders plumbers around here but someone at last came out to take a look at the job, suggesting the possibility of doing works in May if I'm lucky.....

Currently, the extractor fan outlet goes into the blocked up chimney on the other side of that wall. There's black mould all over the ceiling and this is in addition to damp caused by the leaking shower tray under all flooring and on lower part of all walls adjacent to shower room.

Builder has said that they'll need to reposition the extractor fan so that they feed the outlet around the ceiling, through the room wall into an inner hallway, across that ceiling and then outside of the external house wall. This seems to make more sense than the damp going straight into the unused chimney BUT......

A brief look at the ceiling in the shower room and inner hallway made them consider that it might be asbestos. Lots of scary muttering and aghast exclamations followed, with talk of expensive specialist job if there is indeed asbestos there. Gulp!

I want to minimise costs for the works and wonder if they could just leave the ceiling alone, undisturbed and simply fit a more powerful extractor fan feeding into the same place into the chimney?

Can anyone - especially @PigletJohn - advise me whether or not this will still solve the damp problem on the ceiling and upper walls (obviously won't solve the leaking shower tray and damp under the flooring)?

Thanks.

Is there a loft above the bathroom?

Does it have at least one external wall?

Draw some pics please.

@PigletJohn, many thanks for replying.

It's a downstairs room roughly below the upstairs bathroom/upstairs hall and airing cupboard where there's the cylinder. It has no external wall but has one wall adjacent to the dining room and chimney breast and two walls adjacent to the inner hallway.

I'm sorry I can't do/upload pictures but basically, if you come in the front door of the house and turn left ,t here's a very small inner hallway with a toilet on the external wall side and the shower room on the other side of the hallway.

So there's not external wall, no windows and that's why the previous house owners put the extractor fan outlet simply into the chimney wall I suppose.

Current builders think it'd be better to vent the room towards the external house wall but this will mean building an outlet crossing through the inner hallway and then out through the external wall. So that's why they're talking of taking down the ceiling through that whole area and also anyway because the ceiling in the shower room is covered with black mould.

Any thoughts about whether a stronger extractor fan still going into the chimney would be enough to stop further mould and mean the builders don't then have to take down what might be an asbestos ceiling?

Blowing warm steamy air into a brick chimney will cause the water to condense on the brickwork causing damp.

Depending on the direction of joists, you might be able to run a duct between them under the floor above. Or you could run one under the ceiling, preferably in the angle of wall and ceiling where it will be less obtrusive. Rectangular duct is available.

If the room above has an outside wall, you could go up through the ceiling and out through that.

Asbestos ceilings are unusual. Do they mean asbestolux boarding, or do they mean old artex which might, of might not, contain asbestos? Samples can be tested.
Or is this an old industrial boiler room?

I think you need a quiet inline ducted fan with a throughput around 240 cu.m/hr and an overrun timer. There are a few very good ones. If you have numerous steamy showers you may need more.

How high is your hall ceiling, and what are the dimensions of the hall?

Re the asbestos, we had our hall, kitchen., utility room tested for asbestos before new kitchen work.
Was £210 about 4 years ago. (North Wales).
House built in 1989.

Can they not route the trunking through the wall into the toilet room?
If you were in the toilet room you’d see a box up against the ceiling taking the trunking to the outside wall.

Also consider two extractors?

Do you have to have a shower room downstairs or could a shower go above bath in upstairs bathroom?

If you carefully take your own samples you can post them off and asbestos testing is only about £20 a sample.

Thanks for all this help. Will measure hall ceiling height and hall dimensions, @PigletJohn. I think we need the most powerful possible fan as when DCs are at home (uni. aged) they shower twice a day each and one of them takes at least 30 mins per shower!!

Any suggestions for super-powerful ones?

I think the builders mean artex, as there are a few ceilings in the house with stippled 'paper' or whatever it is, including inner hall and downstairs toilet and shower room but also my own bedroom plus upstairs office/spare bedroom!

@tanstaafl, thanks for the pricing. That's less than what I'd thought it might be. Basically, between this inner shower room (off the right side of the inner hall) and the toilet (off the left side of the inner hall) is the inner hall. So any duct would need to pass across the top of the inner hall ceiling to reach the toilet room.

Added complication is that the house boiler is in the toilet room above the toilet with lots of pipe work (currently also with a leaking/dripping TF1 Filter, just to add to the current problems!) and the toilet ceiling is lower than the rest of the inner hall and shower room. So I assume all the pipework for the cylinder in the airing cupboard upstairs above here, is housed in ceiling above toilet. So any duct might be best travelling further to avoid toilet room and out of the inner hall external wall?

House built in mid 1930s and previous owners may just have painted over what was already there.

@Ciderjolly, I asked builders/plumber about a shower over the upstairs bath but they said it would decrease the property price. It would be difficult to fix one there as the bathroom is tiny and the screen for any shower above bath would then 'cut in half' visually, the window.

@Geneticsbunny, I'm a bit reluctant to take my own samples in case I breathe in toxic dust or the ceilings start to come down or something and I'm also not sure which parts of the house need testing.

A main issue is also that locally, no workmen are available for anything at present. They're all very very busy and fully booked up. So even finding a trustworthy company to check for asbestos and then getting someone to come out could take weeks/months, unless these types of companies are less busy than general builders and plumbers.

@PigletJohn, I'll go and measure the dimensions of the inner hall, including ceiling height now. This is all very helpful. Just wish I'd been taught useful building/plumbing and home maintenance at school!

I completely understand but if there isn't any asbestos then it would speed your building work up by several months. I have taken samples of plaster and board and there are ways to make it relatively safe. They only need a tiny bit.

It is likely to be in things which look like plasterboard and possibly in swirly artex plaster. Can also be in that colourful 70's and 60's lino and rubbery edging for stairs and sometimes in glue for flooring. If it is boarding then it has a distinctive texture. If you post a pic then I can say if it needs testing. I am not an expert but have renovated 3 houses whilst living in them and have deal with asbestos on several occasions.

@Geneticsbunny, it certainly seems worth me considering taking samples myself therefore. It's the ceilings they're worried about which see to have a sort of stippled covering.

@PigletJohn, I've measured the inner hall dimensions: ceiling height is about 8ft. Length of hall is about 12ft long by about 10ft wide - within which is the shower room at about 5.5ft by 6ft (but with an area taken out of that by a small hall alcove to hang coats, on the other side).

Does that help?

This inner hall would have originally been the old kitchen for the 1930s house.

@Geneticsbunny, you're being very helpful. Thanks. I'm not able to take and upload pictures not at all tech-savvy I'm afraid) but basically, the ceilings look stippled rather than swirly.

The flooring in the inner hall is some sort of linoleum or lookalike which I think is stuff with glue over what could be herringbone parquet and clay tiling. I was about to try cutting this and pulling it up but if it's got asbestos in any part of it, would that be a bit risky without protective gear?

Most builders sling in a budget 4" fan rated at about 80 cu.m/hr. This is adequate for a WC, or a room with bath but no shower, provided it is run for a good time.

For a room with shower, 240 cu.m/hr is usually fine, and I think the best you can get with a 4" (100mm) duct.

the best brand I know is Soler & Palau (also branded as Envirovent, their UK subsidiary). Wire it so it comes on with the light switch as some people have an aversion to ventilation and will not turn on fans or open windows.

www.tlc-direct.co.uk/Products/SLTD250SILENTslashT.html this one is very good and has a run-on timer

If you want even more power, you would need a bigger duct. This one is 5" (125mm) and there are larger available.
www.tlc-direct.co.uk/Products/SLTD350SILENTslashT.

These ducted fans are quite big and are mostly fitted in lofts or cupboards, as they won't recess into a wall. If you have a duct, you could box it in there.

I strongly recommend rigid plastic (or insulated) duct, installed with a slight fall to the outside so that any condensation will drip out, and not pool or run into the bathroom. The flexible convoluted hose is very bad for collecting fluff and water in the grooves. It is often used because it needs no care in fitting

@PigletJohn, many thanks for this further advice. That's very helpful.

When you say, "these ducted fans are quite big and are mostly fitted in lofts or cupboards, as they won't recess into a wall. If you have a duct, you could box it in there". What do you mean by that last sentence?

The duct would need to go along the ceiling edge of the shower room, through the wall and into the inner hallway, across that ceiling and then out of the external wall on the other side of the inner hall and so will be an obvious 'change' to the ceiling area because of the duct.

If therefore the duct has to go up and then along, for quite a long way, rather than just up and out, will this still be feasible for extracting damp? Won't it, in time, cause damp issues with the inner hall ceiling along which it'll travel?

"Won't it, in time, cause damp issues with the inner hall ceiling along which it'll travel?"

no reason why it should, the duct is a plastic pipe. Warm, steamy air blowing along inside it will not escape until it blows out of the vent on the outside of the house. If you have an airing cupboard or something you could put it in there.

The shell (which includes the sound-deadening layers) of the "250" fan is described as "Width: 575mm inc 4 inch
option reducers - included
Width: 470mm max
Height: 252mm inc bracket
Depth: 204mm"

the fan is fatter than the duct, so it might look better if it was wnclosed in the bathroom, with a grill on the end for the intake to suck through.

It is powerful enough that it does not need to be directly above the shower, but the inlet should be close to the ceiling, because water vapour is lighter than air, so it rises in the room.

An inline fan can be anywhere along the duct. At either end, in the middle, or anywhere else.

The ducts are usually round, but you can get rectangular ones that might be less obstrusive if you can put them in the angle of a wall and ceiling.

You might prefer the look if the duct was enclosed in a plasterboard or other boxing in, decorated to match the ceiling, then it would look like a beam or something.

I don't think I understand your descripton, can you post a sketch plan?

@mutterphore sorry for some reason I didn't spot you had replied. If the lino isn't bright swirly 70's or 60's colours it is reasonably safe to assume it doesn't have asbestos in. Even if it did, the fibers can't get out easily so it is pretty safe. If you want to sample the ceiling then you need an n95 mask from a DIY shop and one of those all over paper suits, a hammer and a chisel, some duct tape, a sandwich bag ,a ladder and a vacuum cleaner. Suit up and put the mask on. Use the chisel and hammer to take a very small sample, just chip off one of the spikes if you can. Put the sample in the sandwich bag. Tape the damaged area with dict tape the prevent any dust coming out. Hoover thoroughly. Go outside and remove the suit and mask and bin them. Stick your clothes straight in the wash and have a good shower. To be honest the suit and showering are probably overkill but it is always good to be as safe as possible.