Dehumidifier in loft?

Grandad2b

I'm wondering whether it's wise to run a dehumidifier in an unheated loft space. I can think of all sorts of reasons not to - the main one being someone has to get up there to empty the reservoir which might have to be daily. I suppose the way around that would be to run a drain hose out through the eaves but then what happens if it freezes up?

The reason I'm wondering is that earlier this year I installed a new platform and some additional insulation in the loft and when I went up to bring down the xmas decs I found that some of the newspaper they'd been wrapped in felt a bit damp.

Now I don't know if this happened every year - I normally have no involvement with the decs - but because I'd moved everything around they were behind some other stuff. I don't think I blocked any of the existing ventilation but the airflow might have changed because stuff got moved around and the new insulation should mean it's a little bit cooler up there than it was in previous years. Also I should probably mention that the old header tanks for hot water and central heating got taken out in the summer which was what spurred me into action on the platform and insulation.

Obviously it's only been a few months since the insulation upgrade and so far this slight change is the only change I've noticed. I feel like it's worthwhile trying to reduce the humidity in the loftspace. Might using the dehumidifier on the landing be enough to make a difference?

Thanks for your insight

FlorayG

The eaves are open to the outside, or should be. You would be trying to dehumidify the rest of the world

Albermarle

Similar thread could be of interest.
Another attic condensation post — MoneySavingExpert Forum

Grandad2b

FlorayG said:

The eaves are open to the outside, or should be. You would be trying to dehumidify the rest of the world

That did occur to me. But probably not as fruitless as trying to dehumidify the inside of a narrowboat.

Grandad2b

Albermarle said:

Similar thread could be of interest.
Another attic condensation post — MoneySavingExpert Forum

Yes, I thought someone would have asked a similar question.

Grandad2b

I've done a little more research and it seems that compressor type dehumidifiers are not recommended at lower temperatures which pretty conclusively knocks my idea on the head.

Eldi_Dos

Grandad2b said:

I've done a little more research and it seems that compressor type dehumidifiers are not recommended at lower temperatures which pretty conclusively knocks my idea on the head.

If you are just proposing to put a dehumidifier on the upstairs landing unless your house is cold a compressor dehumidifier should be in its operational temperature range.Will not have any effect on loftspace if the hatch is well fitted and insulated.

As to humidity in loftspace it is good policy to stow boxes so there is a airflow round them.

MACKEM99

FlorayG said:

The eaves are open to the outside, or should be. You would be trying to dehumidify the rest of the world

Bit like the massive cost to us all in trying to get to net zero when our contribution to the world' s pollution is miniscule in comparison to other countries!

dr_bogenbroom

Grandad2b said:

Albermarle said:

Similar thread could be of interest.
Another attic condensation post — MoneySavingExpert Forum

Yes, I thought someone would have asked a similar question.

This was me - my felt was literally dripping with moisture though. It’s bone dry now though with the warmer weather we’ve been having. Getting roof vents installed in Jan. 

Grandad2b

Eldi_Dos said:

If you are just proposing to put a dehumidifier on the upstairs landing unless your house is cold a compressor dehumidifier should be in its operational temperature range.Will not have any effect on loftspace if the hatch is well fitted and insulated.

I expect that's true in a modern house with a vapour barrier between the top of the ceiling and the bottom of the insulation. Sadly not all homes meet this standard.

Grandad2b

Minor update: installed a basic 100mm extractor in the gable end at the weekend. For now the switch is by the loft hatch so I can manually run it for a few minutes as I feel necessary. Like when it gets ridiculously hot in the bedrooms in summer. And when it gets cold and we're drying washing indoors.

At some point I'll put in a smart socket and temperature and humidity sensors and automate it.