Multi Fuel Stove & Window Condensation

WHU

Hi all,

We have always had a problem with condensation on two of our bedroom windows, and it varies in how bad it can be through the winter months.
This year the problem has spread to every window in the bungalow, and is very bad, to the extent that every morning it is running down the glass.
The only change to the house is that we removed an open fireplace and fitted a 5kw multi fuel stove. We are only burning wood, and for the last couple of weeks have only been burning kiln dried beech, so the water content is very low in it. We only store in the house what wood we are using for the night.

Any thoughts as to why this could be happening? Vents are open, we sleep with the window cracked open while we sleep, but every morning it is the same.

Thanks in advance.

MicktheMan

From what you describe, it sounds like you have a ventilation issue. Your house is now probably a bit warmer because of the stove and as a result the air can support more water vapour which is condensing on cooler surfaces. Added to this, you have reduced the natural ventilation because of the stove and reduced airflow through the flue.

It may be useful to buy a small digital humidity monitor to see where you are as regards moisture in the air. Anything at or above 70% over a prolonged period is high risk for condensation and mould growth. With good ventilation you should be aiming for less that 55-60% expecially when it's cold outside.

WHU

Thank you MicktheMan,
I did think that about the reduced airflow through the flue may be causing it but didn't know why. I'll definitely look into getting a digital humidity monitor, thanks again for the response and the advice.

MicktheMan

Also think about unnecessarily adding to the moisture load of the house like avoiding drying clothes indoors and make sure that extractor fans are effective and used regularly. A lot of bathroom fans are rendered ineffective due to the extra work they need to do because of poor ducting layout etc.

WHU

Thanks again MicktheMan

TPM

MicktheMan wrote: »

From what you describe, it sounds like you have a ventilation issue. Your house is now probably a bit warmer because of the stove and as a result the air can support more water vapour which is condensing on cooler surfaces. Added to this, you have reduced the natural ventilation because of the stove and reduced airflow through the flue.

It may be useful to buy a small digital humidity monitor to see where you are as regards moisture in the air. Anything at or above 70% over a prolonged period is high risk for condensation and mould growth. With good ventilation you should be aiming for less that 55-60% expecially when it's cold outside.

+1 to above

But a more serious thing to consider is that if the ventilation is this bad is carbon monoxide which can be lethal.

all solid fuel and gas produces carbon monoxide when burnt this can enter the rooms if there isnt sufficient ventilation

WHU

Thank you TPM,

I agree I think it is a ventilation problem, I've had a dehumidifier running all yesterday and the windows were a lot better this morning.
After reading your post, I also rushed out and bought a carbon monoxide alarm just in case - thanks for pointing that out.