Humidity levels for my garage

[Sean Walker]

I finally caved and got a mini split installed (Heat and A/C) and was wondering what humidity levels are acceptable for the lumber? Right now my garage is setting at 75 - 76 degrees and 71% humidity levels. Are these numbers OK? Any information would be appreciated.

Thanks

[Charlie MacGregor]

Can you adjust RH independant of temperature. If possible I would try for a lower relative humidity.

[Sean Walker]

I don't know. I will check the manual. It's a Mitsubishi brand that has a dehumidify mode, but that won't cool the room.

[David Hawxhurst]

ideal RH is 45-50%, but being a garage i'm not so sure that would be feasible to maintain.

[Steve Keathley]

Cooling mode will also dehumidify the room. Don't think it's adjustable though.

[Bruce Page]

My shop sits at 10%-20% relative humidity... naturally.

[John Hays]

I have a Gree mini-split and keep it set at 76 degrees, which in turn lowers the humidity to anywhere from 40% to 60% (depending on what the condition is outside) in a 550 sqft. fully insulated garage. On extremely humid days, I get about 70% in the shop, but I consider that pretty good for Georgia in the summer.

[Michael N Taylor]

I have a basement shop and I run a dehumidifier all the time to keep it at 55% humidity in the summer, that is as low as I can get it with one unit running. I would think the garage would be harder to keep low unless it is insulated well and the overhead door is rarely used.

[Wayne Crider]

The obvious big problem for you is going to be infiltration thru the garage door/entrance door from bad seals/gaps, and holes from anything penetrating the ceiling if you wish to lower the RH. Have you checked the RH in your house in comparison. The thing is, is not that the RH will change, which is obvious, but is it necessarily a bad thing as concerns the wood or anything you build out of it. Not only do I think back to the furniture makers of previous generations that never had air conditioning and how their products survived but I also think of the myriad of non air conditioned shops where all manner of things are being produced out of wood today and sold thru out the world; And what of English woodworkers of the 1700's and on. Outside of the wood being green, I think that it would be more important that the wood be at equilibrium and that it would be better not kept in a situation where moisture is being pulled out of it in a environment that is not normal. A/C good for you, but is it good for the wood? I ask.

[Jim Neeley]

I finally caved and got a mini split installed (Heat and A/C) and was wondering what humidity levels are acceptable for the lumber? Right now my garage is setting at 75 - 76 degrees and 71% humidity levels. Are these numbers OK? Any information would be appreciated.

Thanks

Sean,


In regards to your project wood and your shop / garage's RH (assuming dry not green wood), the ideal RH would be equal to the RH in the environment where it will end up, assuming that is a constant. Wood expands and contracts with changes in humidity and allowances must be made when the above is not the case.

[Sean Walker]

Well, the problem that I face every time I get lumber is it twists on me, so that's why I'm trying to get it figured out.

[Mel Fulks]

Just read thread again ,don't see species . What kind of lumber have you been buying ?

[John Hays]

Well, the problem that I face every time I get lumber is it twists on me, so that's why I'm trying to get it figured out.

Heh, that happens to just about every piece of wood I buy these days... of course, I probably wouldn't have this problem if I had another wood source besides the BORGs. *sigh*

[Sean Walker]

I mainly buy Cherry, Walnut, Poplar and Rock Maple from my sawmill.

[Alan Lightstone]

My mini split set to 74 degrees also gets down to the 40-60% RH. And that's in South Florida. With the system off - easily 80%RH or more - I'm certainly in an environment far more humid than in Lexington, though your city is much prettier. Are you sure your mini-split is large enough for your workshop? Oh, and Bruce - we dream about RH that low.