Garage dehumidification

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I have a single skin brick wall detached garage. The cold and damp weather recently has meant that condensation has built up on all cold surfaces. I have an old chest freezer which has a puddle underneath it due to dripping condensation. The motorbikes are all wet, and all containers of liquid are also wet. I figure a dehumidifier is the answer.

Does anyone else run one in a similar setup and if so, what sort of spec should I aim for? Would a “20l per day” spec do the job. One of my concerns is that the tank capacity of these is around 4l, meaning it would need to be emptied 5 times a day. Is that right? I’d prefer something I could leave running and pretty much forget about - or at least have a few days between emptying.

Also, what’s the ballpark cost of running my one of these in a garage throughout the winter months?

What do you recommend OcUK?
 
Soldato
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I wouldn't even bother with a dehumidifier as your garage isn't insulated at all so it'll be as cold and damp as it is outside and you'd essentially be dehumidifying the world!

I'd sooner invest in insulated covers for anything of note and anything you don't want to get damaged remove from the garage.

Edit

Actually are there any airbricks on opposite sides of your garage? My dad's garage isn't insulated, it gets cold but it's never been damp as such. Might just be a ventilation issue that you've got.
 
Man of Honour
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I hadn’t considered ventilation. There aren’t any air bricks. The only ventilation I can see is the gap beneath the garage door. All of the walls are solid and there doesn’t seem to be any ventilation built into the pitched slate roof.

It was built new in 2019 so I’d expect it would be compliant with any regs...if there are any?
 
Tea Drinker
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Regs for a garage no not really.

Be the old boy down my road who lifts his garage door by 12 inches every day it’s not raining to keep his immaculate 1996 Almera immaculate.
 
Soldato
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Regs for a garage no not really.

Be the old boy down my road who lifts his garage door by 12 inches every day it’s not raining to keep his immaculate 1996 Almera immaculate.

There are regs for garages. Not sure on English regs certainly but in Scotland, don't need anything under 30m2 but between 30 and 60 you should have high and low cents on opposite sides. Over 60 and you need mechanical ventilation as well.
 
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We have a section concrete garage and that gets damp when its really cold. Although if I open the door at the front for a few hours it does tend to dry really quickly. There are two fridges and a dryer in there as well.
 
Caporegime
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Got a dehum in the garage which is single skin brick and has cars and bikes in, i'll see if I can read its capacity tomorrow. It works well though.

You can also often find good second hand deals on them because lots of people buy them to solve a temporary problem.
 
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Opening the door could work most of the time, but there are times when we get a front of warmer moist air after a cold spell that still results in condensation on the cold surfaces, even outside in the open. I’m thinking if I plugged the gap under the garage door that a dehumidifier could take enough moisture out of the air to keep it in check.

The ideal situation I think would be to convert to a double skin construction and put a radiator in there but I’m guessing that would cost a lot and impinge on the available space.
 
Associate
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If it has power, put some tube heaters in there on timers for the night and a dehumidifier......that’s what I got in my man cave to keep my E bikes dry and warm in the winter and nothing gets damp and mouldy. Got all my tools etc etc in there too
 
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Tube heaters look like a possibility I hadn’t considered. How many do you think I’d need for a single garage?
I’d put one on each wall if you can......or a small heater on a timer, that runs for 10/15mins every hour or every two hours
 
Soldato
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I've a dehumidifier on a timer with a drainage hose. It works well. Make sure the door is well sealed, as otherwise, you're fighting a losing battle.

Make sure you get a dessicant dehumidifier, as condenser dehumidifiers don't work well at low temperatures.

Edit - I have a Meaco DD8 Junior
 
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I have a detached double garage; single brick, pitched roof with separate attic storage so has a ceiling.
I use a cheap desiccant dehumidifier I got from Amazon years ago for around £80, originally for my shed; it looks essentially the same as this one (It's clearly a multi-brand China special):

https://www.amazon.co.uk/EcoAir-CLASSIC-Desiccant-Dehumidifier-Ioniser/dp/B07N2TT512

I don't have any real water ingress issues so don't know how it would work out in a concrete sectional garage etc with leaks, but for the purpose of keeping the temperature ever so slightly up & dehumidifying enough so that condensation on tools & fabric getting damp isn't an issue, it works great.

On low power draws around 150w & I empty it every 2-3 days, but you can hook up a drain tube.
 
Soldato
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Tube heaters look like a possibility I hadn’t considered. How many do you think I’d need for a single garage?

It takes a lot of electric to raise the temperature in an uninsulated garage. I put a 2.5kw heater on when working in the cold and that can take an hour to raise the temp by 2 degrees, cant have it on too long as it costs a fortune.

I dont get why garages arent insulated now, it would cost sod all if they did it with the rest of the house and most garages are used for storage which ideally should be a stable temperature.
 

SPG

SPG

Soldato
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Very easy job to put on insulated layer just did half my sectional for that very reason for cycling room.

It does sound more like and airflow issue more than anything else though. Waste of time putting in a de-humidifier in though you will be trying to dehumidify the earth.
 
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Very easy job to put on insulated layer just did half my sectional for that very reason for cycling room.

It does sound more like and airflow issue more than anything else though. Waste of time putting in a de-humidifier in though you will be trying to dehumidify the earth.

What did your insulation job involve?

I think part of my problem is the sheer amount of stuff in there preventing good airflow.
 
Associate
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What did your insulation job involve?

I think part of my problem is the sheer amount of stuff in there preventing good airflow.
Insulation is easy to put up......1” x 1” buttons on the walls, 25mm insulation boards in between and then either plaster board or osb board over the top. But I would then insulate the roof too and also add an extractor fan, to help with air movement and the removal of damp air. Again put it on a timer to run for 10mins or so every hour
 
Man of Honour
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Insulation is easy to put up......1” x 1” buttons on the walls, 25mm insulation boards in between and then either plaster board or osb board over the top. But I would then insulate the roof too and also add an extractor fan, to help with air movement and the removal of damp air. Again put it on a timer to run for 10mins or so every hour
Can that be done on a single skin wall? During driving rain some damp makes it through the brick.
 
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