Wet UFH for small bathroom or heated towel rail?

[MetricMs]

Hi, I’m completely redoing a small bathroom and I’d love some thoughts on wet UFH. One builder said that for the size I’d be better off just having a heated towel rack.

It’s a ground floor bathroom, I will be replacing the current floor tiles with new tiles. I don’t know what is under the tiles, the living areas are wood but the kitchen seems to be concrete, there’s a chance the bathroom is also concrete (1920’s house).

I have mould issues despite having a half decent fan as the room is so small. It’s my ‘family’ bathroom used by myself and teens (who spend far too long in there...). I thought that the UFH may help evaporate some of the condensation faster to help relieve the mould growth?

Any thoughts?

I would have both. In our last house we had electric UFH and a heated towel rail (part of gas central heating system). In this house we have just had wet UFH installed and will be having an electric heated towel rail fitted (no gas central heating). We are having an ASHP so towel rail will be seperate from heating system

You need to address the ventilation if you have mould growth

Thank you @TheGallopingGourmet

I have gas central heating, probably should have mentioned that.

I don’t think there’s much more I can do about the ventilation - I will be adding a stronger fan but as it is the fan I have is set to run for 20 minutes post shower, I have a trickle vent (?) on the window plus there’s a gap under the bathroom door that supposedly helps with airflow.

That’s partly why I thought UFH would be a good idea. But the room is so small I’m not sure if it’s worth it with the costs involved (I don’t want electric UFH).

That said the room is so small it needs all the help I can give it!

Can you get a "smart" extractor fan, they keep running until humidity reaches a certain (set) level. Got ours on Amazon.

Thanks @Wilma55 I am going to get one of those! The strongest one I can find.

I’m also moving a wall - bathroom is currently 1.7m x 1.6m so it’s no surprise that it struggles with the moisture levels. It will still be quite small though, for a family bathroom, hence the UFH idea.

Do you kind me asking what brand fan you bought? Are you happy with it?

We have a continuous ventilation fan , expensive but recommended by our damp specialist.

show us a picture of the fan you have please. Is it a 100mm fan?

Does it go straight through the wall, or is there a duct?

A towel rail will not heat the room. Apart from having less heat output than a radiator of the same size, you will be lagging it in a thick layer of cotton towels to insulate it and prevent the heat escaping.

Sounds like you need a better extractor fan. If the budget will stretch I’d always get under floor heating though as it’s lovely not to have cold tiles. We have electric and it’s great. I also rate having an electric towel rail rather than one connected to the central heating so you have the option to just flick it on to dry towels.

Electric ufh is the way to go - much easier to install. Mind you I've only ever had heated towel rails in bathrooms and they heat them up just fine. But it would be nice not to have cold tiles floors!

We have electric ufh in our conservatory and it is amazing. We went for that over wet ufh as apparently less likely to be issues later on.

In our small bathroom we have a heated towel rail and it is fine for heating but we can't cover it in towels.

13 years ago we built a ground floor extension for a kitchen and bathroom and utility. The underfloor heating is fab,

BUT we have 1m of concrete and 25cm of celotex underneath.

If you go down the heated towel rail route, make sure you can heat with central heating and electric.

@Madcats

13 years ago we built a ground floor extension for a kitchen and bathroom and utility. The underfloor heating is fab,

BUT we have 1m of concrete and 25cm of celotex underneath.

If you go down the heated towel rail route, make sure you can heat with central heating and electric.

unless you are lucky enough to have a hot-water cuylinder nearby.

Because then you can heat the rail whenever the cylinder is heated (typically during and after a bath or shower. Ideal.)

www.google.com/aclk?sa=L&ai=DChcSEwj_yIX_mYf0AhWHre0KHbHNCKMYABAKGgJkZw&ae=2&sig=AOD64_0t-GsfyOhbkzpRYuM4MvnRrm9K0A&ctype=5&q=&ved=2ahUKEwjJ0P3-mYf0AhWMZMAKHdAdDZoQwg96BAgBEBA&adurl=

This is our fan. Not had it long but seems good.

Gosh lots of responses, thank you!

That’s the fan that has been recommended to me @Theteapotsbrokenspout , I have that on my To buy list.

@PigletJohn the current fan goes horizontally through the wall to outside, it’s a ground floor bathroom with a bedroom above so I assume I can’t take it through to the loft? From what I can see the actual fan is around 100ml. But the bathroom is tiny and with 3 teens and myself it has to work hard.

Everything will be ripped out and replaced - the airflow icon fan is the one that my plumber recommended, would that be good?

Combi boiler at the other end of the house so no hot water cylinder I can utilise.

@Bobbybobbins for some reason I thought wet UFH was less likely to cause issues than electric, have you had it long?

Photo of fan - I have given up on the bathroom so it’s not as clean as it should be!

About 6 years - my DH is an electrician so he may be biased towards the dry!

Both if you can! Though I have no idea about wet or dry being better/ cheaper.

Better ventilation is necessary but won’t be as effective if the room surfaces are cold and the water condenses onto them too easily. So the key is to warm the room up unless you always leave a window open.

I think I would go for a plumbed in heated towel rail and a radiator. And if possible heat the coldest wall.

This is all very helpful, thank you all!

I don’t think I can fit a rail and radiator but I can add one of the tallest towel rails (may help?), and I think I can relocate it to the coldest wall. I didn’t know about that thank you - currently the radiator is on the ‘hottest’ wall.

I’ll look a for dual fuel towel rail.

I’ll add the icon fan and it looks like electric UFH is best for the area?

@PigletJohn am I right in thinking I can’t vent a fan through to the loft as the bathroom is on the ground floor? I will be adding an en-suite above the bathroom so the ductwork could be hidden in the walls but I’m guessing the distance involved may reduce the efficiency?

Our downstairs bathroom is pretty similar in size (1.5x1.8 approx). We have an extractor fan, window and a vertical radiator to heat it. So far we've found the radiator is good enough to provide heat and to keep room dry (only had bathroom completed in march so this is the first winter in there). The fan and window seem to keep the condensation away and provide enough ventilation. Underfloor heating would've been nice but definitely wasn't in our budget unfortunately.

Also had this dilemma. Went for a radiator with heated heated rail. Glad we didn’t go for underfloor heating. The room is so small, no more than 2x3m, the bath mat means you don’t get cold feet out of the shower. Other than a daily bath and a few toilet trips, we don’t use it long enough to justify underfloor heating, I’d be forever turning it on and off! The towel rail means it’s very toasty. We have underfloor elsewhere though (dry), and I love it. I would say to try and get an electric towel rail though or if you have smart heating, then that’s fine, but it would be useful to be able to put it on in the summer to dry the towels without having to switch the heating on!

if you don't have a loft above you will probablt vent straight through the wall. If you have an airing cupboard or something you could put a ducted fan in there, they are a bit to big to wanr one on display in the room.

Alternatively, you could have a larger hole in the wall. A 100mm wall fan will have a throughput of about 80 cu.m/hr, this is quite typical of builders' bathroom fans and not really enough if you have steamy showers. Good example here at 95 cu.m/hr from a superior brand. But this 6-inch/150mm size has 280 cu.m/hr which I consider adequate.

These examples have timers but not trickle speed. I have not included humidity sensors as I don't consider them much good.

The model with trickle speed could be left running continuously, which would probably keep the bathroom pretty dry, though I have not used them. I think they are more common in WCs.

If space is an issue there are radiators that combine with towel rails like these here www.heatandplumb.com/acatalog/radiator-towel-rails but I’m sure there’s many more styles and suppliers. I saw screwfiz had something for about £150.

It’s BTUs that count - British Thermal Units ie heat output you need for the room size. There are sites out there that tell you what size rad and BTU you need for your room. A radiator gives more BTUs than a heated rail of the same size but a combo might be a good compromise.

My dream is to have a wide towel rail rather than just tall vertical, so each towel dries more quickly and efficiently, and doesn’t just steam up the one above!

Yes agree Bonelle that a electric rail gives summer options for when the central heating is off. That’s why I think I’d opt for a plumbed radiator and a separate electric towel rail if possible.

(I’ve been giving this lots of thought over the years waiting for the day we can finally re-vamp the bathroom!)

if you have an en-suite above, then yes, you could have a concealed duct. A ducted fan can be quieter than an in-wall one.

it is possible to use use a ducted fan to vent two rooms, by joining the pipes together, but I don't recommend it. Sound and odours might find their way from one room to the other.

As we move inmto the 1970's and beyond, I think measuring energy in kW will become more common.

numbers in BTUs look much bigger and more impressive, which is why I think radiator salesmen like them.

but you probably know what a 1kW heater does, or a 3kW one.