Mould growth in garage?

[Hsmith192]

Hi everyone,

I’ve noticed there is some mould growth in the near corner of the garage and some spots of mould on the new plywood top that was added only three months ago.

Insulation is limited with nothing on the walls and it was been a very wet and windy set of months.

How can I combat this?

 

[Spectric]

Need some heat to dry things out and a little ventilation to remove dampness.

 

[Hornbeam]

Ventilation is key. Also treat the mould that is present to kill it and the spores otherwise it will come back at te first opportunity

 

[Ttrees]

Bare 3/4" plywood seems the worst for mold, same way with my shed, even if stuff is well off the floor.
I have some gloss painted shelves made from thinner ply quite close to the floor, and it doesn't seem to attract it though.
Maybe I should stick the few bits I've made from the 3/4" ply over a bit of heat, and give it a coat of something.
With what though...
I'd rather oil them with linseed, but will that prevent it?

What treatment is out there to kill it off?

Thanks
Tom

.

 

[thetyreman]

increasing ventilation is definitely the key, and trying to decrease the amount of water and damp that gets inside as well, unless you sort out the issues the mould will just come back, it's worth looking at the stucture and seeing if there are other causes such as a wet outside wall, blocked drains or gutters that kind of thing, as well as looking at improving airflow.

 

[shed9]

A spray bottle with very diluted bleach will remove the mould that is there, give it a light spray and leave for an hour or two. Make sure there is plenty of ventilation when you do it and wear the appropriate face mask / ventilator - you do not want bleach in your throat, airways or lungs.

As in the comments above, good ventilation and removing damp is key to ensuring it doesn't come back but that in itself is very dependent on the inside environment, time of year and thermal break between outside and in - only way to remedy that is to insulate and ventilate properly.

 

[Ttrees]

Cheers folks, was thinking about bleach, was thinking of something a little more toxic in the long term though, might give that a shot all the same.
Done big job with french drainage when we got here, basically sitting on a spring, been looking to get some concrete moulded ones to put grids on for the other end, but never found any for very cheap.

Improving the airflow further wouldn't be worth it, no rust issues now.
I cemented in the doors from water ingress, never opening for multiple reasons, drafty enough as is,and no insulation in the workshop which would likely make matters worse, if I had.

Keen to keep the clutter in the way for lots of reasons, rather than making the place that much more draughty.
Thankfully I don't have that much ply, a saw vice, bit covering the TS for jigs sometime, log sled for the bandsaw, and a lamp base.
Be easy to chuck a layer of dust on top to keep from happening.
Don't plan on having too much of it around apart from the odd jig.
as it won't grow on the toxic timbers I have
Only on the wee bits of green timbers drying is what it likes.

Still pondering about a coating of something, but wouldn't want white gloss paint flecks on some stuff like sleds, like with shelves.
Would like a clear finish on some of the ply, and something that penetrates rather than wearing off.
Linseed seems a bit 'natural' to me, maybe clear coat of 'non edible' lacquer might be a half ar5ed solution, but seeking something more permanent.

Thanks folks
Tom

 

[Hsmith192]

Thanks everyone, I’ll try to increase the ventilation and get rid of the spot of mould using some bleach/anti bacterial.

I do need to look at the guttering- could be too much water on external walls.

It’s a concrete fabrication that is single skin with no insulation but has two doors so it might be useful to keep them open in the next couple of workshop sessions.

Thanks for the support everyone. Does anybody recommend insulation to keep the moisture issues down at all?

 

[Hornbeam]

Is the moisture condensation or water entry/damp in the walls?

 

[mikej460]

I would invest in a basic moisture meter and test if there is damp ingress or rising damp problem; also buy a simple temp/humidity gauge, I have a La Crosse Technology Temperature Station WS9024 and it is excellent. Bear in mind that if the surrounding humidity is on the high side then as long as damp air can get in and not out (even through ventilation) then you risk mould. You might need a dehumidifier and possibly low level heat permanently running. Does water condense on the inside roof?

 

[--Tom--]

Depends where the damp is coming from- through damp walls, a damp floor, or through doors etc.
Guttering to keep the walls dry, drainage around the walls, well fitted doors will all help.

Once the structure is dry, air flow will help with condensation issues.

insulation will help but only once the structure is dry. If it’s damp the insulation would serve no benefit unless done very carefully and intentionally the address specific issues

 

[Hsmith192]

Hi everyone,

sorry for my late reply- I brought a hygrometer and have some pictures of the readings.
It’s only went to 80% during the night? Ever time I use the workshop it sits at 50-60%.

please have a look and let me know what you think

 

[Woody2Shoes]

Your meter readings are not very meaningful without a lot more context. Please describe the materials that floor, walls and ceiling are made of, the level of exposure of the site (near the sea?), sheltered from prevailing wind? guttering, overhanging trees/roofs, any heat sources? Ventilation is crucial, but it has to be effective (cross ventilation with no dead zones). Etc etc.

 

[Hsmith192]

Ok, it’s concrete floor and walls and the ceiling is metal framed with a concrete roof.
Sheltered from winds, not near the seas. No overhanging branches.
Thanks for your reply.

 

[minilathe22]

Check whether you have a damp proof membrane low down just above the ground. It will be a black plastic layer between the bricks. Any soil/debris leaning on the bricks above the DPM will let moisture travel in. Dig soil away from the walls if needed.

Also as you have suggested the guttering needs to be in good order.