I'm off to build my own workshop for mostly woodworking projects in the (huge) basement garage of a very old house. The garage is about 5 by 30 meters(16 by 100 ft) and has a varying height of 3 to 6 meters (10 to 20 ft). It has just a huge garage door (approx 4 by 4 meters (13ft)) and no windows.

I haven't gotten around to test all the corners for their average humidity, but I fear that it may vary quite drastically from season to season (Central Europe) and even be different in various locations inside the place.

I think I'd be aiming for somewhere around 40%?!? in average humidity and hope that to the rear of the room (which is basically a dead end tunnel) the humidity will drop and I can store and dry my lumber there.

Is there a "rule of thumb" for the ideal workshop humidity level? Are there some tricks I can use to bring it down to some degree without using "expensive to buy and run" machines?

In winter I will probably heat the place up with a gas powered heater as it's fast and relatively cheap but I fear that this will cause fast and rapid changes in humidity -> which I think is quite bad.

  • To reduce humidity, you can run a dehumidifier, though air leakage through the garage door will put some additional load on that.
    – keshlam
    Commented May 19, 2016 at 16:10
  • I know, and in my opinion that's the least desirable way to go as the place is huge. I have air-leakage (as you mentioned) and the thing would put a huge strain on my power bill.
    – Stoppal
    Commented May 20, 2016 at 7:56
  • Outside of improving your ability to keep moisture out, there isn't much alternative. For small spaces a bucket of silica gel, baked periodically to release the moisture it has trapped, can work... But that doesn't help you.
    – keshlam
    Commented May 20, 2016 at 12:14

1 Answer 1


There's a lot written about the ideal conditions for the workshop but you have to be careful about the source since the figures quoted aren't as universal as sometimes implied or stated, some sources not taking into account very different conditions to theirs (much drier or much damper).

For example it's much damper in the British Isles generally than in most parts of the US, so the figures we often see quoted for wood moisture content (MC) on American sites and in the forums just aren't realistic for Britain or Ireland and it would be a mistake to match them even if this was practical.

Is there a "rule of thumb" for the ideal workshop humidity level?

Yes. The bottom line is this, proper humidity for a workshop depends on where you are. It should match, or be close to, the typical humidity of domestic interiors where you live if you're making pieces for the home.

It doesn't matter then if the MC is even double (yes, double, or even higher) that quoted as normal or average in North America, it's correct for where the finished items will live.

  • Thanks, so i'm going to buch-order some humidity sensors and find the averages not only in the shop, but also in my rooms. I searched for data on regional humidity and thought i could take that into account, but according to your answer this data isn't as important as i initially guessed, as the moisture content in domestic housing depends on insulation, wall-thickness and other factors that may keep a room dry or not.
    – Stoppal
    Commented May 20, 2016 at 10:12
  • 2
    @Stoppal, if you have a weather station near where you live you might be able to use the data from Weather Underground to find out your local humidity. Our local weather stations all collect humidity readings but the national weather service never gives it (!) however the information is shown on Wunderground, which is how I found out that local humidity is above 80% through most of the year.
    – Graphus
    Commented May 20, 2016 at 16:36
  • @Graphus >80% humidity year round? Ugh! I'd move!! Otherwise, +1 for the Wunderground.com recommendation.
    – FreeMan
    Commented May 20, 2016 at 19:34
  • @FreeMan, I'd move too given the chance! Luckily temps are moderate so it doesn't feel too bad, but RH can reach 100% regularly at certain times of year and that's ugh for sure.
    – Graphus
    Commented May 21, 2016 at 8:48

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.