Best ventilation system for old 1930s bungalow

[irishbo]

Hi guys I recently moved into a 1930s bungalow on the Wirral , soon after moving in a realised the house is suffering from condensation, damp and relative humidity in the 80s ,I bought a Meaco dehumidifier and had it in the hallway but the noise drove me mad , it ran constantly and only got the humidity down to mid 60s , it never achieved a relative humidity 50% , I gave up on that idea and after loads of research  I fitted a nuaire drimaster in the central hallway and although it freshens the air it’s also freezing and does not drop the high relative humidity, nuaire initially told me it would ,I  have  a humidistat fitted in the loft and if it’s 86% humidity outside the loft will be 83% and obviously this is getting blown into the house so I can’t see how it’s going to help my issue ,     I live by the book with regards to keeping humidity low all the boxes have been ticked and I still struggle  , I also live alone ,  I’m just wondering would a mvhr system be better for me as regards to lowering humidity and making the air fresher or am I just going to have to live in a cold damp house with windows open all year round 

[ProDave]

People scorn putting an mvhr into an old house that is not particularly air tight, but I suspect in this case it will work well.  My impression from owning a 1930's house is the actual walls are pretty air tight, it was usually the rubbish windows and doors that made them leak like a sieve.  In the old days, constant air going up the chimney from the open fires would have kept them fresh.

 

MVHR would give you a constant rate of air change, which need not be very high, while avoiding the problem of the incoming air being cold.

[Iceverge]

@irishbo

 

Are you comfortable with the distinction between absolute and relative humidity?

If air is 99% relative humidity at 10deg and you bring it into your house and heat it to 20deg  the relative humidity will drop to about 50%. 

The absolute humidity will stay the same, about 9g/kg of water vapour. 

 

 

 

I short you need a combination of lower absolute humidity (outside air is almost always lower absolute humidity) and heat to dry out your house.