Domestic Extractor systems

richard83

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Hi guys, I’ve got a problem with my house and could think of nowhere better to get an answer than here! I have 3 bathrooms upstairs (sounds excessive I know), currently only use the main bathroom but in time with decent extraction will use all 3 (as the family grow up etc). Anyway each bathroom has an extractor fan built in to the ceiling, each has ducting going into the loft space and along the roof to an exit point on the side of the house. All these ductings meet each other, it seems a s**t system to me where steam is involved. It is not adequate at all. So I’ve three questions, what’s the best system for 3 bathrooms? 2 are with outside walls so could get there own system on the wall if needed. Who would install the system? An electrician or plumber? (I’m a nurse with little diy knowledge) and thirdly how much roughly do you think it would cost? I’m in Chorley and house maintenance is new to me, kind regards Richard M
 

muskrat

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I don't know nowt about owt when it come to extractors. But we've got a wall mounted extractor in the bathroom and it is rubbish at extracting steam from above its own level.
 

Dave

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Inline fans with ceiling ducts can be more powerful and at the same time quiet compared to wall mounted.
Each fan should have a none return built into the duct and ideally its own outlet. However combining two into one wont cause a problem.
 

richard83

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Thanks for the replies so far. I’ll try and attach some pics later. I think 3 to one ducting is a bit much. As for the non return I can guess that they don’t already have that as water had built up mid duct and I encouraged it down the line and it flooded into the last bathroom along the ducting along with a load of black gunk
 

Arch

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It doesn't work very well, but you can get insulated ducting.
 

Stansthirdboy

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You should be able to install one large fan in the final run of ducting, there has to be a fine balance of taking out the steam and not creating a draught. The fan should be on a timer wired from the light switch so that it stays on for a minute or two when the light is turned off, and comes on when the light is turned on.
If the run from the bathrooms to the main ducting is a long one you may need to fit extra fans inline.
All said after all that, it's best to keep the ducting as short as possible to prevent the steam condensing in the ducting.
This should help
 

John Step

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I believe the ducting should be insulated above the ceiling as cold air will induce condensation and drip down onto the ceiling.
 

Stansthirdboy

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As usual all of the projections contain that little word 'Could' not saying we are not doing damage to the planet but when natural diasters like the volcano in indonesia can put more warmful gasses into the atmosphere in a week than the UK population put in over a decade you have to start asking questions as to how the planet has survived upto now. You also have to ask the question of who is making these predictions, if they are scientists tasked with looking at climate change then of course they are going to say that it is happening as if they just said it's all cyclic and nothing to worry about they would be out of a job.....Climate change is becoming big bussiness with money to be made so of course it is going to bigged up by some people. We need to think about how we tackle this and not just make knee jerk decisions, take the fires in Australia, if the government had'nt banned burning of dead bush would there be as much fuel to maintain the fires....probably not....surely a few controlled fires annually are much better for the environment than a completly out of control huge fire is
I believe the ducting should be insulated above the ceiling as cold air will induce condensation and drip down onto the ceiling.

If possible the ducting should go straight up with no bends. Or straight out through the wall
 

Dave

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Ideally use smooth walled ducting, not the flimsy concertina type.
From the outlet in the ceiling connect an inline fan within a metre of the inlet about 500mm or so higher than the ceiling. This can be done in flexi pipe if required for ease.
Then use smooth walled plastic or metal duct sloping downwards to an external wall such as gable end, or via a roof tile vent.
Any condensation has only one way to go and that is outside.

I've run quite a lot of metal ducting in flats for bathroom extractors and never had a problem with condensation or noise this way. Inline fans are more efficient and powerful than the wall mounted ones, plus as they're not in the same room you cannot generally hear the fan, so lounging in the bath becomes a pleasure.

One thing to bear in mind is fire regulations so always worthwhile checking if you are going to use ducting in roof spaces. Keep the run as short as possible also.

Edit - one plus as well using an inline fan outside of the bathroom does not require Part P of the building regs. As long as you are competent with wiring it can be a DIY job - same as always though, play safe.
 
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tipitinmick

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In - line fans have as much pull as Ukzero1 on new years eve down the working mens. I've fitted Manrose, Silavent , Ventaxia, environvent and they are all rubbish. Go for a 100mm or a 150mm wall mounted fan. If it has a timer or humidi on it, it will need its own means of isolation. IE .... A separate isolating switch. Fitting fans in Bathrooms falls under the Part P building regs so you will need an electrician to fit it and notify the work once its completed.
 

Dave

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I beg to differ, in-line all the way, and don't forget a none return flappy thing :D
 

Lee Richards

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If the OP goes down the route of connecting three extraction points to an inline fan is the fan location a problem if it is as noisy as single extraction fans?
Or even more noisy as it has to be more powerful.
The kids sometimes moan now when I shower at 5.30 and the fan kicks in.
Could just imagine the moaning if the fan is located above their bedrooms.

??
 
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