Condensation issues

[mtt.tr]

The best is positive input, far more effective than extraction but probably not that easily achieved in your situation.

An easy experiment is to put a fan in the door way and crack open a window. You will be taking drier air from elsewhere and displacing the wet air.

In my tiny ensuite I have heater blower fan, this made a vast improvement as we set it to heat the room, raise walls past the due point.
Then post shower leave it on blow for a couple of minutes with no heat completely resolved our issue

 

[Welderpaul]

Are the patchy areas the solid outside walls?

Yes

 

[mtt.tr]

And the report someone had done:

View attachment 399813View attachment 399814

In this case look at a PIV system

 

[Welderpaul]

In this case look at a PIV system

A friend raves about these. The ceiling is boarded on the underside of the rafers so its difficult to get to work in practice. 3 walls are outside walls and the door wall is the bedroom wall.

 

[Gareth J]

Ah, it looks like the currently installed setup is pretty new and decent. Sorry, my input was more suited to a deeper renovation.

In your case, it'd probably pay to just run a dehumidifier if you can easily power it and put up with the object. MVHR through a wall + a bit more heating might be worth investigating.

 

[mtt.tr]

A friend raves about these. The ceiling is boarded on the underside of the rafers so its difficult to get to work in practice. 3 walls are outside walls and the door wall is the bedroom wall.

The system will be placed anywhere you can get it, they are often placed in corridors they effectively pressurise the whole house.




Moisture is the Hardest part of any building to control, we create a lot just living the more we tighten and insulate the worse we make it elsewhere. Ventilation and insulation have to be used together. I'm sure you know this but it's seems to be missed by a good few.

 

[addjunkie]

Your report covers it reallly, you need more insulation, more air flow and non chalky paint. More heat would also help.

Or PIV……non of which is a 5 minute 50 quid fix

 

[Pigeon_Droppings2]

Room heat exchanger would swap out the air whilst retaining the heat...I wouldn't fancy drilling the hole though if the walls are stone!

 

[richie00boy]

Nice bathroom.

Before you go to all the huge lengths suggested so far try changing the extractor fan. Those surface mounted fans are pretty poor, get a Manrose MF100 mixed flow inline fan from Screwfix and some solid 100mm ducting and grille from here

White Circular Ceiling Mounted Vent Grille Adjustable Round Ventilation Diffuser Extract Air -100mm

Available in 100, 125 & 150mm duct sizes. Circular ceiling diffuser finished in brilliant white. Coned sections to disperse air more evenly. Supplied with insect mesh. Can be used for extract and supply air ducts.

www.blauberg.co.uk

I have mine wired to come on with the lights. They do a timer version of the fan with over-run which you might prefer, but this is a little more work to wire up.

 

[Shox Dr]

Put a timer on the shower.

(Pet hate of mine is people running the shower for 10mins+ before they get in.)

 

[Smallfry]

ventilation will help ,,, in any and every form , overrun on fan is a must at the minimum , its just a product of surfaces being colder than others ,,, its a pain and the persistent problem with rentals , tenants wont ventilate as its letting the heat out and so it starts

You are dead right there, and so many landlords are villified for it. Usual cause is drying clothes on radiators or letting tumble dryer vent indoors, because "we don't want to let the heat out innit"
Insulated walls do not stop this either if the room is not heated, but ventilation is the key.

 

[mike os]

i would start with swapping the ceiling fan for a 6 inch mixed flow fan, those ceiling fans are really pants

also trickle vents and some background heat... doesnt need to be hot just warm enough to limit condensation.

 

[Gareth J]

It should be easy to tell if your current fan is up to scratch;

Shower, then immediately check cold surfaces nearby (in your case, you could temporarily prop a small mirror above the door). There should be no condensation until your body/towels let vapor into the air. If the room is getting steamy while you shower, get more flowrate - the inline one mentioned is pretty good in my experience.

If you squeegee and dry the shower after use, fan overrun is not important in my experience. After doing this on ours, the Humidistat doesn't even cut in. Unless the towel rail is on and drying towels. If the shower is dry, overrun isnt doing anything. But fans with them are cheap enough!

Fans need a gap under door too

 

[Morrisman]

i would start with swapping the ceiling fan for a 6 inch mixed flow fan, those ceiling fans are really pants

also trickle vents and some background heat... doesnt need to be hot just warm enough to limit condensation.

The ceiling extractor in my last house was so rubbish it wouldn't even hold a sheet of bog roll up against gravity. I swapped it out for the best one that could be retrofitted, with an adjustable over run timer on it. Made a hell of a difference.

My current place has a big old fashioned Xpelair cut into the window, but with the bathroom door shut there's no air getting into the bathroom, you can tell that when you open the door, the fan tone changes markably. I've put vents in the door, but they don't flow much, it would do better with a 1/2" scarfed off the bottom of the door.

So something else to watch for: make sure you have vents in the door, if bathroom users usually close it. The best extractor in the world won't remove steam if it's trying to pull a vacuum.

The worlds nastiest wiring install, god knows who did it, supposedly a professional bathroom fitter when the previous tenant lived here.

 

[Morris]

When our bathroom was refitted I installed a small MVHR unit with extract over the shower and the supply on the opposite side of the room. It runs at tickover with a boost mode for showers. Works great.
The unit is a vent axia MVHR unit. I installed it myself and total cost was about £800. It was worth it.

 

[Gritineye]

Watch out for convoluted flexible ducting to a fan, they really cut down the flow rate.

Even if the ducting is insulated for it's whole length, condensation will form inside it and puddle in the corrugations.

The mould inside there can sometimes be very bad.

Out of sight out of mind. Just like when you take out a perfectly cleaned cutlery draw out and there is a mat of spiders webs above it that makes the lady of the house scream when you show her.

 

[Morrisman]

Watch out for convoluted flexible ducting to a fan, they really cut down the flow rate.

Even if the ducting is insulated for it's whole length, condensation will form inside it and puddle in the corrugations.

The mould inside there can sometimes be very bad....

Legionnaires disease?

 

[gaz1]

that report is mainly based on scare tactics

whilst trickle vents do help for a change of air within rooms it does allow the heat to escape any report that does state they dont allow the hot air to escape is lieing

trickle vents fitted with high extractor fans will alllow for more air changes within a room as the heated air will rise up and out of the house via this vent and also can be sucked out of the room ( chimneys use this process ) and can create a cold room due to more air changes

heating within a bathroom the towel heater is not enough to warm the room enough therefore the room will remain cold ( colder than the rest of the house ) full tiled bathrooms are the worst for creating cold rooms ( they create cellers due to the mass of cold tile ) cold tiles can be heated by enough heat within the room ( enough radiators )

if a damp meter has been used its a true con/scare tactic

 

[OJCar]

If the condensation is really bad you could consider whistling up a Hydrafoil.

 

[gaz1]

If the condensation is really bad you could consider whistling up a Hydrafoil.

why dont you keep out of it if you have nothing better to say

there was no need to have a dig or have to say something from another post of mine and certainly not on a post that has nothing to do with the subject

instead of bullying and taking the p*** out of a member or could i claim that you are a second account holder on the forum to cause trouble via another account

why arnt you doing something about this then wazaaah as it is against the forum rules that you are actively allowing this to happen, for a forum admin dont you think you should do something about it ?

i can take a joke but some members are actively trying to intimidate, bully, goad members into losing there cool