Wood Storage - Attic

[tri4sale]

With a one car garage as my primary work area, storage space is a premium for me, especially for wood. I try to not have a wood stash, just get what I need, but I have a lot of small pieces of the reclaimed mahogany doors that I need to store. Right now they are mostly in small boxes (see picture) and under my shopbot, but need to find a better place for them.

My question is does anyone store wood in an attic? I have stairs at end of garage that lead up to my floored attic, so I can easily get them up and down when needed. But does the NC heat of summer than the cold of winter and this cycle repeating affect the wood and storing it in the attic? And if it is ok what's the best way to stack? Can I leave them in the boxes, or should I take out and stack with a spacer between the pieces? I think I have about 5 of the small boxes with pieces in them, as well as some longer pieces about 3 feet by 4 inches that I need to store.

 

[Fishbucket]

I store lots of pieces in the garage/shop attic.
Havent had any issues. Already dry wood can be left in the box. If you send green wood up there to dry, sticker as normal.

 

[blackhawk]

I think that it would be risky based on the humidity changes that the attic will see. That type of cycle could definitely create some warpage.

 

[Jeff]

I think that it would be risky based on the humidity changes that the attic will see. That type of cycle could definitely create some warpage.

The relative humidity in NC averages about 12-14% year round.

 

[blackhawk]

Jeff - I assume that you are talking about indoor humidity?

I am assuming that his attic is adequately vented to the outside air via soffit vents and/or gable vents. In that case, the attic humidity will be somewhere between indoor and outside humidity. On long rainy days, I think that the attic could easily get to 70% humidity.

 

[Jeff]

Not talking about indoor humidity but outdoor humidity in an unconditioned air space. In NC the yearly average relative humidity is 70% and the equilibrium moisture content of the wood will be about 13%.

https://www.weather-us.com/en/north-carolina-usa/raleigh-climate#humidity_relative

https://research.cnr.ncsu.edu/blogs...ium-Moisture-Content-of-Wood-Instructions.pdf

Jeff - I assume that you are talking about indoor humidity?

I am assuming that his attic is adequately vented to the outside air via soffit vents and/or gable vents. In that case, the attic humidity will be somewhere between indoor and outside humidity. On long rainy days, I think that the attic could easily get to 70% humidity.

 

[blackhawk]

Jeff - Gotcha, when you said relative humidity in your 1st post instead of moisture content that threw me off.

 

[tri4sale]

Jeff - I assume that you are talking about indoor humidity?

I am assuming that his attic is adequately vented to the outside air via soffit vents and/or gable vents. In that case, the attic humidity will be somewhere between indoor and outside humidity. On long rainy days, I think that the attic could easily get to 70% humidity.

Correct, attic is adequately vented with soffit and ridge vent

 

[scsmith42]

I think that it would be risky based on the humidity changes that the attic will see. That type of cycle could definitely create some warpage.

For most woodworkers, and uninsulated attic spaces is one of the very best places available to store their lumber. It will typically keep lumber below 10% MC.

If you have humidity controlled storage available, that would be the first choice. An attic would be second choice, and is much better than a crawl space or out doors.

 

[blackhawk]

I'm just basing my statement on personal experience. I made casing out of kiln dried lumber. I installed it on 3 doors and 3 windows. All of the installed trim has done fine for over 15 years, no gaps in the miters, no splits, etc. I had 3 pieces leftover that I put in my well ventilated attic. They all warped. Here is a picture of the worst one. It may have just been a fluke due to some unexplained phenomenon, who knows. But after this experience, I just never risked putting any lumber in my attic.

 

[tri4sale]

I'm just basing my statement on personal experience. I made casing out of kiln dried lumber. I installed it on 3 doors and 3 windows. All of the installed trim has done fine for over 15 years, no gaps in the miters, no splits, etc. I had 3 pieces leftover that I put in my well ventilated attic. They all warped. Here is a picture of the worst one. It may have just been a fluke due to some unexplained phenomenon, who knows. But after this experience, I just never risked putting any lumber in my attic.

that's an interesting picture, and that really motivates me to just install some shelving up high in the garage for the wood.

 

[Matt Furjanic]

I have not had an issue with storing all my wood in my attic for 16 years. Wood stays dry and ready for use.

 

[Fishbucket]

I'm just basing my statement on personal experience. I made casing out of kiln dried lumber. I installed it on 3 doors and 3 windows. All of the installed trim has done fine for over 15 years, no gaps in the miters, no splits, etc. I had 3 pieces leftover that I put in my well ventilated attic. They all warped. Here is a picture of the worst one. It may have just been a fluke due to some unexplained phenomenon, who knows. But after this experience, I just never risked putting any lumber in my attic.

I bet that trim you have nailed tight into position that's been caulked and painted would have done the same thing left loose in the attic like that piece...

 

[scsmith42]

I'm just basing my statement on personal experience. I made casing out of kiln dried lumber. I installed it on 3 doors and 3 windows. All of the installed trim has done fine for over 15 years, no gaps in the miters, no splits, etc. I had 3 pieces leftover that I put in my well ventilated attic. They all warped. Here is a picture of the worst one. It may have just been a fluke due to some unexplained phenomenon, who knows. But after this experience, I just never risked putting any lumber in my attic.

Part of the cause was the fact that the casing had millwork done to it that altered the shape of the blank. USually raw lumber that is consistent in thickness will stay flat.

The benefits of attic storage is the very low RH% for most of the year. Most attics are somewhat like a solar kiln; if you store 8% MC lumber in a typical attic it will usually stay below 10% MC.

Not all atticsa re the same though. You mentioned that yours is “well vented” and that may make a difference.