Bit of info required re condensation and dehumidifiers......

[gilford]

I moved in to our house last September. Since then we have had a LOT of plaster work done and also a new bathroom fitted.

We bought new furniturefor the bedroom a few months ago and there was a load of black mould behind the dressers which we were told was due to the large amount of work we had done and not ventilated the house afterwards.

Since then I have tried my best to have the windows open a bit but we have a fire escape window in our bedroom which is very big and opens like a door with no latch or trickle vent on so it is not really feesable to have that open.

Most of the condensation happens in the night while we are sleeping in there (as everyone says). Last weekend my wife noticed that some of the mould had come back in the very bottom corner of the room (outside wall) so I have been to Argos and bought a decent Delonghi DM10 dehumidifier

I have had it on full blast for the past 2 days and I have probably extracted a good 6 litres of water in that time (!).

My question is do I just keep this running ALL of the time in the bedroom or is there a cut off point where I can say thats enough?

How much water is expected to be drawn out of the air?

Should I move it around the house over the coming weeks although there is no sign of condensation in other rooms?

What is the best form of practice with this type of thing?

I have checked and I have insulation above the bedroom along with cavity wall etc. There is an "air brick" on the OUTSIDE wall of the bedroom but there is no vent visible inside?

Any info appreciated, I really dont want to be running the dehumidifier constantly for obvious energy reasons.

Cheers

 

[JohnD]

you can make your own trickle vents by drilling the window frames if they are wood. you can hire a core drill to make neat round holes through walls.

post some pics of the frames

if you have any bad habits such as draping wet washing about the house, or neglecting to use extractor fans in bathroom and kitchen, stop them.

//www.diynot.com/wiki/building:condensation_in_houses

Fresh plaster and emulsion paint are made of water so you have got to ventilate to get rid of it. If you open your loft hatch during the day a lot of airflow will go up there (also heat so it is a bit late in the year). Open whatever windows you can on sunny days and also the internal doors for airflow..

 

[Deluks]

Ultimately, sleeping in an unventilated room is not good practice. So yes, run the dehumidifier or open the window, simple as.

You could fix an adjustable sliding vent in the inside wall, to line up with the outside vent. Could be noisy if you are near a busy road though.

Other options would be to fix a stay to the window so you can have it slightly ajar but still locked, or retrofit a trickle vent. A window 'expert' could probably do this quite easily. My local paper is full of 'window repair men'.

Do you have an extractor fan in your new bathroom?

 

[gilford]

We dont dry clothes in the house, we do that in the conservatory (thats what they are built for right? )

We have a fan in the new bathroom which goes on with the lights and then for 5 minutes after and I tend to leave the bathroom window open for a good while after a shower.

How long will I have to run the dehumidifier for?

What is the "ok limit" of moisture in the air so I know when I can turn it off? I presume around a litre a day extraction?

Cheers