prob a very stupid question but so sick of condensation causing mould inside would weathershield paint work on it inside????

[belcantwait]

we have tried everything. had expensive damp system installed and brand new double glazing throughout but still the mould prob remains. its a very old cottage with no foundations so trad damp course not possible.
the damp readings have improved trememndously but still the mould comes back- same old story- cold outside walls with stuff against them. have to have stuff against them as no room to put all furniture, curtains etc on interior walls only.
would wethaersheild work inside ? or will this make it worse????

Have you tried insulating indoors? When we lived in a top-floor flat under a flat, uninsulated roof, we had a problem with mould in the top of our wardrobes. They were built-in, and the ceiling of the wardrobe was the ceiling of the room, ie the underside of the roof. The only thing we found that stopped the condensation was tiling the ceiling inside the wardrobe with expanded polystyrene tiles. They can be papered over, I believe, though we didn't bother.

Alternatively, you might try Kitchen and Bathroom paint. Once we had repainted in K&B paint we had no more mould problems in our bathroom or kitchen in that flat. K&B paint absorbs excess moisture and slowly releases it as the air dries, so you don't have walls streaming with water all the time.

Condensation is caused by insufficient ventilation. Can be a particular problem in older houses which have had insulation and double glazing installed as the room is hermetically sealed and moisture generated inside the house has nowhere to go. Do your double glazed windows have trickle vents? if so, keep them open as these give some ventilation. Do you have enough airbricks and have you made sure that they are not blocked? Damp proofing will not help as it is not actually a problem with damp getting into the house from outside, but rather that the moisture generated inside the house can't escape. It might be an idea to get a builder to have a look to see if more airbricks might be needed.

You could try posting on a specialist old buildings website or contacting the SPAB, but I really think that if your house is made from traditional materials, using weathershield might cause massive damage to your walls long term.

Daft question, but are you sure it is mould and not efflourescence from bricks caused by the damp?

www.nachi.org/images08/efflorescence-inspection.jpg

If walls are cold, even ventilation may not do the trick. We had no problems ventilating our flat - being on the top floor we could leave windows open 24/7. But under certain circumstances, where there is no airflow - eg inside a wardrobe or behind furniture, then condensation can build up even in a well-ventilated room. We tried a good de-humidifier. It didn't collect much water at all, and made no difference to the condensation. The trouble is that we breathe too much! The only times we closed all our windows were when we were on holiday - there were never any condensation problems when we returned because there had been nobody breathing in the flat.

Echo both Yorkshirerose and Grendelsmum.
If you have trickle vents make sure they're open! I know it gets a bit breezy at times but the moisture has to escape.

hi

thanks for all replies, we dont have trickle vents but i do keep the windows slightly open during the day even in the winter. i keep the air vent on in the bathroom when having a bath and after as well.
we have dutch (???) venting system which pushes air through constantly and these are placed in the wall all around the outside of the house. i thought when we ot the double glazing and everything was properly sealed taht we wouldnt get condensation but we bloody do! its not as bad as it was though (apart from back of house which is north facing and its bad there too) and the added bonus that our lovely old sash windows which were ripped out (sob) are no longer rotting to pieces.
its really getting me down, have just spent morning bleaching the walls to death (have always done so but also advised by damp co), its so depressing the house is lovely but this spoils it for me every bloody winter

oh, and there are 5 of us in house- its wrost in mine and dhs room as more breathing!!!!! ( iguess) -and more
tat tasteful items in the room

I just bought ebac dehumidifier from ebay for my house - my house has had anti-damp course, but I do get condensation.
Dehumidifier collects about 4-5 liters of water per day - and the air starts finally feeling more dry. I cannot imagine where that water sits if not collected!!
Maybe you can try it?

In a previous house with condensation problems, we used kitchen and bathroom paint on the bedroom wall so that we could wipe off any mildewy stuff - it did help but you need to address the casue if it's anyting mjore than just needing better ventilation.

This seems to have worked on our bathroom ceiling where we had terrible mould problems. Our decorator sanded it all down ,cleaned it with anti mould paint and then used outside paint. No problems yet - now about 2 yrs old I think. But I don't know about on outside walls.

Ooh, thanks for this thread, lucysmum's post might be very helpful for my bathroom ceiling mould problems (we do have trickle vents AND I leave the windows open but we still keep getting mould).

Quick hijack for OP. I am getting the dutch system installed this week on the top and bottom of the house - apart from rising damp there is also huge humidity problems upstairs (house is 160 years old) - the company said that it would solve the problems of humidity upstairs so i'm a bit disheartened to hear your story - did you have the top and bottom done?.

I'm a bit at paying out almost 6k to be still wiping down the windows and bleaching the skirting after.

laurie- it has definitely IMProved but..... after we had it done it got significantly worse then it got better. the owner or said company came to look at it and surveyed the whole house and pointed out other things that needed doing- eg new kitchen roof and guttering- still not done as not got the money!, patching up render outside and getting new windows. he did a damp reading and readings were good to average. beforehand they were danger levels with beeping and alarms going off. so tbh i think it has helped but we had to do more than just the system- prob spent double what we orig thought we would - plus still need to get roof done (6k)
apparently houses sometimes do get worse before they get better. ours still isnt brilliant. i do wonder if ours would have been improved anyuway by just getting the windows etc done and not bothering with the system

have used dehumidifiers before - and also stand-alone radiators in wardrobes etc (helped more than the dehumid.) . scray the amount of water they generate!!

laurie- only had the bottom done- which is supposed to spread to the top didnt really understand it tbh but dh seemed to. why are you having it installed top and bottom? is it a masssive house??
oh and we didnt have rising damp so dont know if that makes a difference
there should be a pic of my house on my profile if youre interested

we have a concrete house and have just had sempatap interior insulation fitted on all exterior walls, house feels much warmer straight away and they treated all previous damp areas first so hopefully no more mould.

oh and in case you do look, the first ics are what happened when we tried to 'patch up' the render. not pretty

ilovetochat- that looks interesting- just googled it. what is it made of exactly? and can i ask you how much roughly it cost to buy and put up etc??? did you do it yourself or get specialists in?

it is 10mm thick and hangs on wall like thick wallpaper, it has fibre glass in it so it hardens on the wall and you can paint it, paper over it or even tile on it. down side is every room in our house had 1 undecorated wall so whole house is in need of decoration.
3 bed semi £3500, bathroom was just treated no sempatap in there, all other outside walls done including up stairs.
the rep from sempatap recomended a couple to hang it (he said we could have done it ourselves but i have a 2 yr old and dp works 6 days a week) and it took them 2 days, they cleaned up all mess, were very considerate of me and dd and worked late to fnish.
other alternatives were losing 100mm by boarding/insulating like a false wall, or exterior insulation.
someone suggested polystyrene tiles, we had these and they do work but paper peels off it as the condensation comes through walls and they are a fire risk.

ooh, your house is lovely

no, my house is very small but its detached which means that there is a lot of places to get damp, there is only a maximum of 11 feet between two external walls. We have rising damp up to a metre downstairs - we're on a hill too so the water is soaked up like a sponge through the terrible render (which is frankly holding the house together).

The upstairs is all humidity problems which they say will be fixed by having the 'system' put in upstairs.

I will wait and see if thats true.

mould comes off wall with shower shine but the pores are released into the air during cleaning.