Bathroom Extractor Fan Help

akira181

I live in a Glasgow tenement and have one of those long-ish and narrow bathrooms (~1.3m x 3.5m). Currently I have an extractor fan mounted to the window. It's pretty loud and the room is still quite steamy after a shower but the fan clears it in a little while after the shower is turned off. The shower is door side, not window side of the bathroom so probably doesn't help much but there's no mould issues after 5 years of living here, so it must be doing something.
The windows are super old, leaking in some rooms, and I need to get them replaced. I'm wondering if I should keep the window mounted bathroom fan or move it into the ceiling? I'm top floor and have access to the loft.
If the latter, how best to get the vent to outside? Is it possible to vent through the eaves or is through a roof tile the best bet?If it's possible to go through the eaves, I would be looking to DIY it. Being an old tenement building, there isn't a soffit fitted but just a relatively narrow (if memory serves) gap between the wall and roof. Can someone suggest what sort of vent cover I should be looking for?

If via the roof, I would be taking a chance with a contractor (haven't found a reliable/competent roofer yet since my last one moved away).

ThisIsWeird

The ceiling option will surely cost a lot more, especially if you need to get someone in to fit the outlet. Would this require scaffolding?
I cannot comment on the suitability of the gap you have between the wall and roof, but if it's, say, the best part of an inch, then a decent DIYer should be able to fabricate a suitably-wide outlet to slip in there to exhaust the fumes. This would need to be wide enough to match the rest of the ducting, so ballpark ~400mm-ish? 
You can almost certainly get a much quieter version of your current window fan, but - let's face it - they are ugly, and will be the noisiest option.
I don't think the fact the window fan is at the end of the room is, in itself, an issue, as the replenishing air will be coming in from the opposite end, from around the door, so forming a nice waft to guide the steam away. Once out of the shower, I'd be inclined to leave the door only slightly ajar, and not fully open, so as to not cause large swirls that could make the steam escape out the door itself - you don't want that.
So, your current setup seemingly works 'fine', but is ugly and noisy. A centrally - or slightly closer to the window - ceiling fan would look a lot better, be a lot quieter, and you could fit a powerful beast to ensure thorough venting, but you'd need to weigh up the cost. I'd suggest that if you'd need a contractor to access the roof, it would be prohibitive. And you just don't need it.
Can you see your current window fan? Is it ugly?! Could it be disguised by a new blind, say a wide-slatted timber Venetian? If so, a nice new quieter model would be the 'sensible' option

Eldi_Dos

If the window opening is tall enough could a panel be fitted at top and extractor fan fitted into that, then new window fitted into the rest of the window opening.

akira181

ThisIsWeird said:

Can you see your current window fan? Is it ugly?! Could it be disguised by a new blind, say a wide-slatted timber Venetian? If so, a nice new quieter model would be the 'sensible' option

It's in the top part of the tilt and turn window and sticks out about 3 inches. It's clearly visible, presumably old/cheap (so loud and bigger than it needs to be), and makes opening the window a bit sketchy. A lot of weight for an already somewhat oversized tilt and turn window (~2200mm x 900mm).

Current plan is to have the top 600mm of the window a fixed pane, and have the fan go through that. 

If there's enough space to do the install from within the attic, I would be doing the install myself and getting my brother-in-law to wire it up as he's an electrician. The pitch of my roof is quite shallow though, so I'm not hopeful that I'll get enough access

ThisIsWeird

Since you are replacing the window in any case, then doing what you propose would be by far the cheapest and easiest option. And also effective.
The only drawbacks I can think of are the extra noise, and the fugliness. 
If you do go for this option, why would you give that top section a full 600mm of height, when only, I guess, 300mm or so is needed? That would allow a larger opening section below. Is it for aesthetics - a more balanced appearance? If so, fair enough.

I guess, have a good crawl in the loft, and see if an extracting method is possible. Do make sure your choice of vent outlet will eject the steam beyond any timbers. And will presumably also need a grill of a certain size.

akira181

If I can get enough access to install an attic fan, I'll probably have to end up making an exhaust grille that will fit in the eaves. Either finding one close to the right size and cutting it up or just 3D printing one from scratch. That should hopefully get the exhaust air far enough away from the roofline and prevent any condensation directly dripping on the wall. If not, I'll upgrade for a hopefully quieter window extractor.

600mm is purely for aesthetics. I got 3 windows on the back elevation so would be looking to get a matching design across them all. I thought a narrow strip of glass across the top would look a little odd, with the frame being 72mm  but looking at the 30cm ruler on my desk, it's not all that narrow. I think I need to use masking tape to mark out 300mm and 600mm on my current windows and take a proper look.

ThisIsWeird

akira181 said:

If I can get enough access to install an attic fan, I'll probably have to end up making an exhaust grille that will fit in the eaves. Either finding one close to the right size and cutting it up or just 3D printing one from scratch. That should hopefully get the exhaust air far enough away from the roofline and prevent any condensation directly dripping on the wall. If not, I'll upgrade for a hopefully quieter extractor.

600mm is purely for aesthetics. I got 3 windows on the back elevation so would be looking to get a matching design across them all. I thought a narrow strip of glass across the top would look a little odd, with the frame being 72mm  but looking at the 30cm ruler on my desk, it's not all that narrow. I think I need to use masking tape to mark out 300mm and 600mm on my current windows and take a proper look.

3D printing? Oookkkaaay! You've got this sussed, I suspect

I wouldn't actually worry about condensation dripping on to the brickwork below the vent, as the amount will be tiny, and most will be projected away from the wall as vapour in any case. My only concern would be if the exhaust were to land on timber parts such as the insides of the fascia board. As long as the vent's nozzle is a tiny bit beyond that, there should be no issues I can think of.

akira181

3d printing is easier to learn than you'd think and they've gotten really cheap of late.Can pick up a pretty decent one for around £150. Difficult thing is actually finding useful things to print. I mainly used it for DIY stuff like small oddly shaped bits (the grille for example), shims, or precise support pieces to get angles correct.

Going to brave the fibreglass and go up into the attic tonight or tomorrow, get this figured out properly and get on with replacing the windows

ThisIsWeird

Keep us posted

akira181

ThisIsWeird said:

Keep us posted

I crawled along the attic joists as far as I could before my head was scraping the nails coming through the roof and I still couldn’t see the eaves, nevermind get access to it. Not a problem for wasps though, they built a basketball sized next there. At least I found out why there were so many of the little buggers getting into the flat last summer.

I’m going to have to keep the extractor in the window but will upgrade to a hopefully much quieter one.  

I did toy with the idea of 3D printing the window adapter and getting a Vent Axia Svara. Low profile, not hideous looking, and extremely quiet. But just too expensive (wish they made a Svara without the Bluetooth/Smart features), too much added complexity, and having 3D prints completely exposed to the elements generally isn't a good idea.

Going for this window kit (https://www.extractorfanworld.co.uk/tornado-stwk-4100mm-window-kit-6091-p.asp) and one of the Silent Tornado 25dB fans. If I find that too loud still, I'll consider tackling the complexity to make a quieter fan fit.

ThisIsWeird

Sounds like a good bet.

25dB = Sound of breathing at 1m distance

You aren't going to get much quieter than that, regardless of type. My ceiling fan, with a mid-mounted in-line fan - is louder.