Garage and Damp - not car related, but something else
Discussion
Hey all,
I was hoping someone could offer advice -
We have a single brick, concrete floor garage what’s currently storing a lot of moneys worth of wood. At the moment there’s no sign of mould. It can feel damp in there at times, but not convinced thats damp, just cold if you know what I mean
I do have the garage well ventilated - I can open the garage door to leave a 1ft gap at the top and bottom of the garage door, it’s my understanding the ventilation will help. But Im concerned this may not be enough
I have a couple of humidity sensors in there and they are currently reading 85% relative humidity - which I have a feeling is close to the outside of the garage.
Anyway, I know people on here are quire knowledgable about these sorts of things so looking for advice and tips really
Cheers!
I was hoping someone could offer advice -
We have a single brick, concrete floor garage what’s currently storing a lot of moneys worth of wood. At the moment there’s no sign of mould. It can feel damp in there at times, but not convinced thats damp, just cold if you know what I mean
I do have the garage well ventilated - I can open the garage door to leave a 1ft gap at the top and bottom of the garage door, it’s my understanding the ventilation will help. But Im concerned this may not be enough
I have a couple of humidity sensors in there and they are currently reading 85% relative humidity - which I have a feeling is close to the outside of the garage.
Anyway, I know people on here are quire knowledgable about these sorts of things so looking for advice and tips really
Cheers!
Dunno where you are in the country, but it's been humidity in the 80+% over most of the South of England most of the month.
The problem is when you take a garage at 80% humidity in the after noon, say 18deg, and let it cool overnight, relative humidity will increase and you will get dew on cold surfaces.
My garage workshop, I try to stop it cooling too much overnight and I try to air it during the day.
If I'm trying to dry something like a boat, I use a small amount of heat and a dehumidifier
I'd guess a large amount of wood will hold a lot of heat so temperature swings in the garage won't be so bad?
The problem is when you take a garage at 80% humidity in the after noon, say 18deg, and let it cool overnight, relative humidity will increase and you will get dew on cold surfaces.
My garage workshop, I try to stop it cooling too much overnight and I try to air it during the day.
If I'm trying to dry something like a boat, I use a small amount of heat and a dehumidifier
I'd guess a large amount of wood will hold a lot of heat so temperature swings in the garage won't be so bad?
You need a bit of air, not a door wide open.
Then put some pallets on the floor. This will encourage airflow beneath the wood
Usually it is the wood touching the cold and slightly damp floor, that results in mould.
If the wood is large enough to lay direct on to the pallet - great. If not, lay some ply on top of the pallet.
If you want to take the next step, get a dehumidifier. These guys are brilliant. All staff super knowledgable about garage and humidity.
But, your wood will never be 'kiln dried' FYI.
Then put some pallets on the floor. This will encourage airflow beneath the wood
Usually it is the wood touching the cold and slightly damp floor, that results in mould.
If the wood is large enough to lay direct on to the pallet - great. If not, lay some ply on top of the pallet.
If you want to take the next step, get a dehumidifier. These guys are brilliant. All staff super knowledgable about garage and humidity.
But, your wood will never be 'kiln dried' FYI.
Do you know if your garage has a DPC?
My garage is a concrete sectional garage that was here when we bought the house. Very prone to damp. No DPC. Much improved by waiting until a good dry spell then covering the floor with a good coat of bitumen paint.
The other thing I did was - the wall were erected on a base that extended out a round 6 or 9" beyond. Rain tended to pool here. So I mixed sharp sand and cement and went round adding an angled layer so rain runs off. Again after a dry spell I painted this and the bottom couple of inches with bitumen.
It's still not fantastic but far better than it was. Anything important and prone to damage from damp air gets kept in the 14x10ft shed I built with my dad. Proper DPC, concrete base and double wall construction.
My garage is a concrete sectional garage that was here when we bought the house. Very prone to damp. No DPC. Much improved by waiting until a good dry spell then covering the floor with a good coat of bitumen paint.
The other thing I did was - the wall were erected on a base that extended out a round 6 or 9" beyond. Rain tended to pool here. So I mixed sharp sand and cement and went round adding an angled layer so rain runs off. Again after a dry spell I painted this and the bottom couple of inches with bitumen.
It's still not fantastic but far better than it was. Anything important and prone to damage from damp air gets kept in the 14x10ft shed I built with my dad. Proper DPC, concrete base and double wall construction.
Evoluzione said:
Your garage is acting like, er, a garage.
If you want it to act like your house then add another wall, lots of insulation and some heating.
^^^ ThisIf you want it to act like your house then add another wall, lots of insulation and some heating.
Mushymatt said:
I have a couple of humidity sensors in there and they are currently reading 85% relative humidity - which I have a feeling is close to the outside of the garage.
Why would you expect it to be less than external, if it's unheated?At best, with good ventilation, it will be equal to external RH. At worst, trapping moisture in there and with no ventilation or direct warmth from the sun to dry it out, it will be a little higher.
Don't confuse RH with the moisture content of the timber though (athough the latter will track RH to some degree)... it's the moisture content of the wood you need to be checking (with a protimeter). If the moisture content of the wood is above 16-17%, you've got a problem (assuming it wasn't green when you put it in there). If it's above 21%, you've got a big problem.
Remember back in the day all timber for use as furniture was air dried, ie seasoned.
The focus should be on how it’s stacked and keeping the rain off (which you have done as it’s in a garage) rather than worrying about the humidity.
Stacking it correctly and allowing airflow is the most important.
Basically the timber needs to be off the floor by laying it on battens and then timber and then battens and then timber etc etc . Just make sure the battens are the same thickness and line up with the ones below it as you go. Take your time stacking it. I use to find an enjoyable experience correctly stacking timber.
Whatever you do, don’t cover the timber with a tarpaulin because that will restrict airflow. Ideally you’d have the garage door open a few inches one end and a window on the latch open the other.
The focus should be on how it’s stacked and keeping the rain off (which you have done as it’s in a garage) rather than worrying about the humidity.
Stacking it correctly and allowing airflow is the most important.
Basically the timber needs to be off the floor by laying it on battens and then timber and then battens and then timber etc etc . Just make sure the battens are the same thickness and line up with the ones below it as you go. Take your time stacking it. I use to find an enjoyable experience correctly stacking timber.
Whatever you do, don’t cover the timber with a tarpaulin because that will restrict airflow. Ideally you’d have the garage door open a few inches one end and a window on the latch open the other.
Edited by Wozy68 on Tuesday 1st November 07:36
What sort of timber is it you're storing?
I keep quite a lot of plane finished cedar and larch for a business in an open sided shed - it stays in perfectly good condition if it's stacked properly, even surrounded by a damp, North facing Aberdeenshire forest.
Stack it well off the ground in single layers with plenty of bearers or battens between each layer - you basically want every face of the wood to be in free air. I tried double layers so only one side of the timber was exposed and some mould spots appeared.
I keep quite a lot of plane finished cedar and larch for a business in an open sided shed - it stays in perfectly good condition if it's stacked properly, even surrounded by a damp, North facing Aberdeenshire forest.
Stack it well off the ground in single layers with plenty of bearers or battens between each layer - you basically want every face of the wood to be in free air. I tried double layers so only one side of the timber was exposed and some mould spots appeared.
Wacky Racer said:
Dehumidifiers cost a LOT of money to run usually.
I was just coming on to say dehumidifiers don't cost a lot to run.
I've been using one in our garage since March and haven't noticed any real extra use of leccy.
Mind, we've got economy 7, so I actually use 2 during the cheapo period & one with a RH % preset during the other 17 hours.
2 sMoKiN bArReLs said:
I was just coming on to say dehumidifiers don't cost a lot to run.
I've been using one in our garage since March and haven't noticed any real extra use of leccy.
Mind, we've got economy 7, so I actually use 2 during the cheapo period & one with a RH % preset during the other 17 hours.
Of course if you run it on a timer plug then that'll cost less, and if you've got cheaper electricity off-peak (economy 7 or an electric car tariff) then that'll reduce the costs even further. But it won't be free, sadly!
blueacid said:
2 sMoKiN bArReLs said:
I was just coming on to say dehumidifiers don't cost a lot to run. I've been using one in our garage since March and haven't noticed any real extra use of leccy. Mind, we've got economy 7, so I actually use 2 during the cheapo period & one with a RH % preset during the other 17 hours. This is my daytime
https://www.machinemart.co.uk/p/clarke-dh30l-30-li...
You can preset the rh & also drain either outside or into a large container
https://www.machinemart.co.uk/p/clarke-dh30l-30-li...
You can preset the rh & also drain either outside or into a large container
Evoluzione said:
Your garage is acting like, er, a garage.
If you want it to act like your house then add another wall, lots of insulation and some heating.
Accurate, if not a little blunt.If you want it to act like your house then add another wall, lots of insulation and some heating.
OP, I am guessing that two of three bricks up on the single skinned wall, you will find a membrane to stop the damp rising?
If you so, your concrete floor is below that line and will get damp.
Your easiest option is put some plastic sheeting down, to stop the damp transferring directly onto the lowest stacked wood.
RichB said:
What types of dehumidifier are you chaps using? I'm considering one for my treble garage but wouldn't know where to start in terms of size/power etc.
Thing to watch for is type. There are the ones that work like fridges. There are the dessicant type. The latter work better at low temps.https://www.climatedry.co.uk/info-hub/article/what...
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