Condensation , perfect storm.

[kendo57]

Opened my garage this morning to be confronted by everything covered in beads of water.
My lathe and mill which i only used yesterday were a lovely orange colour. My chucks and vices
looked like they had been outside for 6 months not overnight in a garage.
Genuinely felt like crying this morning , spent the time wiping things down and then scotchbrite
with oil.
Not to mention my scooter and BMW , i will be cleaning them tomorrow.
Had to deal with condensation before but never seen it on this scale.

[weeksy]

Yup, same yesterday but not terrible. Happens about 2-3 times a year in mine and you can basically tell as it's from cold into humid/wet. I don't know what the answer is in truth. My garage is quite draughty and I think that often helps, but at times I guess not

[Skub]

I feel your pain @kendo57
As thee knows,it's the sudden big temperature changes that do the damage. Even with a radiator in my garage,the temperatures have been 4° or 5°then yesterday it leapt to 15°. Everything cold just blooms with condensation.
The best solution I've found is to preempt these conditions by watching the weather forecasts and have the dehumidifier rolling before the change comes.
It was @Tricky who put me onto my Meaco DD8L Junior and it's been a godsend. On the low setting it uses one kilowatt (28p) every three hours,so not a big strain on the household budget. It's a lot better than continually trying to manage the inevitable condensation and the destruction it can cause over the Winter months.

[weeksy]

Does that require the garage to be pretty much air tight though? Otherwise you're just sucking water out of constant airflow?

[mangocrazy]

Where you are in the country and the level of temperature swings experienced play the major part, but the construction of your shed/garage/workshop also plays a big part, as does the level of insulation it has. Uninsulated metal construction is the worst, as the temperature changes outside are very quickly translated to interior temps. A combination of improved insulation and, as Skub says, a dehumidifier on standby would be my front line defence.

[mangocrazy]

Does that require the garage to be pretty much air tight though? Otherwise you're just sucking water out of constant airflow?

It's a tricky one. Airflow can help with condensation, but it also means that changes in temperature occur quickly inside the structure. And if you have a really leaky shed/garage then a dehumidifier will be working overtime for little real effect. Making the structure airtight and increasing insulation should be your first port of call I think.

[weeksy]

That's not going to happen as it'd mean a new door, likely a roller door which would be £1500. We're moving house in 18 months so won't be laying that out.

[Skub]

Does that require the garage to be pretty much air tight though? Otherwise you're just sucking water out of constant airflow?

In a perfect world having a well sealed garage is a good thing for sure. Mine is damage limitation,as the old up and over door lets a lot of draught around it. Certainly the dehumidifier would have a lot less work to do if the door sealed better,but it still does a great job of keeping things dry in there even as things are. The door is a work in progress for me.

[mangocrazy]

I'm fortunate in that my shed is a re-purposed (brick built) Victorian wash house/outside toilet at the end of the garden, and I've heavily insulated the roof structure. Door is wooden, so there's minimal metal to conduct heat/cold inside.

[weeksy]

Does that require the garage to be pretty much air tight though? Otherwise you're just sucking water out of constant airflow?

In a perfect world having a well sealed garage is a good thing for sure. Mine is damage limitation,as the old up and over door lets a lot of draught around it. Certainly the dehumidifier would have a lot less work to do if the door sealed better,but it still does a great job of keeping things dry in there even as things are. The door is a work in progress for me.

I'm watching one now on eBay

[Skub]

I'm watching one now on eBay

It's a done deal then.

[weeksy]

I'm watching one now on eBay

It's a done deal then.

Depends, I'm not paying £200 for one

[kendo57]

Unfortunately my garage is a single brick construction and sits at the bottom of my garden.
It would be easier to knock it down and build a new one than try and insulate it.
I have managed ok for the last 24 years though so i will just have to suck it up.
As Skub says, i bit of pre planning would have helped so i will bare that in mind in future.

[MrLongbeard]

I used to leave a 300w tube heater running 24 / 7 that kept the condensation away (double skin garage) but with current leccy costs it's been turned off.

I did try one of the Meacco dehumidifiers, worked a treat but garage was so drafty it was running at max power 24/7 to keep on top of it, again leccy costs put paid to that idea.

[weeksy]

Well it just gave me a reason to go in the garage and strip everything off all the shelves and dump a tonne of crap. So it was mostly worthwhile

[Skub]

I used to leave a 300w tube heater running 24 / 7 that kept the condensation away (double skin garage) but with current leccy costs it's been turned off.

I did try one of the Meacco dehumidifiers, worked a treat but garage was so drafty it was running at max power 24/7 to keep on top of it, again leccy costs put paid to that idea.

Rather than run the Meaco 24/7 I try to judge when the big temperature fluctuations are coming. If there's a cold stretch lasting weeks,or if it's mild continuously it's hardly used. It's the contrast between the two when it comes into play.

Might save damage to the household account.

[mangocrazy]

The Meaco DD8L does have different power settings, and even on low power I found it made the shed a nicer place to be in the colder months. And the water that's extracted from the air is effectively distilled/deionised, so you don't need to buy any when topping up a battery...

[weeksy]

Well it just gave me a reason to go in the garage and strip everything off all the shelves and dump a tonne of crap. So it was mostly worthwhile

IMG_20241124_165303 by Steve Weeks, on Flickr

[demographic]

Unfortunately my garage is a single brick construction and sits at the bottom of my garden.
It would be easier to knock it down and build a new one than try and insulate it.
I have managed ok for the last 24 years though so i will just have to suck it up.
As Skub says, i bit of pre planning would have helped so i will bare that in mind in future.

Potentially you could dot and dab insulated plasterboard on the inside of the building, think last time my brother did some he got the price per sheet of the 35mm overall (10mm plasterboard with 25mm insulation on the back of it) down to £27 per sheet and that was only about a year ago. Well worth haggling and most sheds dont take that many sheets to do the walls as theyre 1200x2400.

[MingtheMerciless]

Two tubular shed heaters around 300W live under the ZH2 to keep condensation off it and they work well in an Asgard shed.