Drying pressure treated syp

[Jim Chance]

Hi,

I use pressure treated southern yellow pine to build trail structures. I use 2x6, 2x8, 2x12, 4x6, 6x6, and 8x8. The wood is usually soaking wet when I get it. I would like to dry it mostly so it is not so heavy to carry. Is there an easy way to do this? I have a garage with a dehumidifier. My bit of experimenting with storing them in a dehumidified place looks like it caused cracking. I had the dehumidifier set on 30% and had a fan blowing on the lumber. I live in a pretty humid area.

[doc henderson]

Jim first of all, what kind of outdoor structures are you building.  It may be fine to build wet and accept some shrinkage.  If outside, then it only needs to dry to the EMC of your area and not less.  the dry conditions will help it lose moisture due to increased moisture gradient; but may result in more cracking.  I would decide if the weight to lift and MC need to be addressed prior to building.  I would prob. stack them so they get air flow out of the sun and eat you Weatties on build day.

[Jim Chance]

It is more about weight than shrinkage. My next project requires 1.5 mile hand carry in on a rough and narrow foot trail. Biggest pieces are 2x12x16 and 8x8x5.

[beenthere]

Jim
Sticker them and let them air dry.
It won't take long to do that, and you also will be able to easily sort out the badly warped pieces rather than having them warp along your trail structures.

[doc henderson]

Well Jim, here I just thought you were whining about carrying them across your backyard.    where are you? how oldish are you?  how wide and how rough a trail, what kind of slope?  what are you building?  if you do not mind me asking?  can you take stuff in on a two-wheel cart with big bike wheels in the center of a stack so guide the load and push, but not support the weight?  I agree with air drying.  you can even weigh a representative board and check to see the percent weight loss.  of course, different dimensions will lose at different rates.  volume to surface area ratios.

[Wlmedley]

I'm pretty sure you can buy kiln dried treated lumber. I bought it when I built my house almost 40 years ago to use on my porch floor. They were  2" x6"s and they were dry enough to paint which I did . They were a little more expensive but they were worth it being I had no shrinkage after installing and paint stayed on good. They were a lot lighter than regular treated lumber.

[barbender]

I'd second just stickering and stacking it to air dry.

[TreefarmerNN]

I'm pretty sure you can buy kiln dried treated lumber. I bought it when I built my house almost 40 years ago to use on my porch floor. They were  2" x6"s and they were dry enough to paint which I did . They were a little more expensive but they were worth it being I had no shrinkage after installing and paint stayed on good. They were a lot lighter than regular treated lumber.

Yep, they should be marked "kiln dried after treatment" or KDAT. 

[K-Guy]

You can dry them with a dehumidifier but be aware, the chemicals are very corrosive and will greatly shorten the life of anything that gets the moisture on it.

[Jim Chance]

I am in western North Carolina in the blue ridge mountains. We are building hiker bridges. The trails are generally less than 10% slope except for short sections. In addition to Hand carrying we sometimes use a tracked carrier and sometimes use a big wheel hand truck. We attach the board to the hand truck with a ratchet strap with the wheel about 1/3 of the way from the end. The tracked carrier rolls over when there is too much side slope. The hand truck can handle rougher trails, but for my next bridge, the tread is too bad for either. I am 68. Our groups average age is 73.i think my other option is skidding them. I have a portable capstan winch. I mostly use it for moving rock. This stuff is sort of light and fragile to drag with a winch. My other option is to do a bunch of tread work. 

KDAT is not readily available around here. You can order it.

[Jim Chance]

These are bridges destroyed by Helene.

[Jim Chance]

And if I stack it in the garage, should I run the dehumifier at all? And how long would I need to stack it?

[doc henderson]

Well, if it involves any volume at all you will want to exchange the air in the garage.  Is it airconditioned?  For this stuff, there is no reason to risk sheet rock or mold in your garage.  I would sticker it on a flat surface preferable outside.  cover the top but not the sides.  It is done when you feel it is light enough to carry it up the trail.  How long are the bridges on average?

[doc henderson]

Our scout troop rebuilt this one from 20 feet long with a drop and lift at each end, to 36 feet long with approaches built so the length of the bridge is a steady incline.  It was built with very fresh PT lumber, with a brown color.



I am third from the right.

We also had to hand carry the wood.  but not very far.  mountains west of Colorado Srings, Camp Alexander.





this waterway has running water almost any day it rains up in the hills.

[barbender]

You'd be better off stacking and stickering it outdoors, where it can get a breeze. I'd imagine it will dry quite quickly, because it is free water (not in the wood cells) so it isn't like drying green wood. Even if it was green, pine dries quickly on stickers.

[beenthere]

Protect the stickered stack with rain cover only on top, with sides open. Suspect three weeks would do what you want/need.

Back when I built my deck, I stickered all the deck material and stacked in the garage with couple box window fans and doors open. Did not take 3 weeks.

[beenthere]

For moving the lumber on the trails, give the hikers some boards to take with them on their hike, on a volunteer basis. Seems they would be more than happy to help build the bridges desired for their hiking trails. 

[scsmith42]

I too would suggest that you stack and sticker the wet PT lumber outside with tin over the stacks.  If you want to accelerate the drying, add some fans blowing on the sides of the stacks.  

In a few weeks the lumber should be fairly dry.  Your only risk is that there may be some wood movement during the "re" drying process that would cause you to reject some boards.

Regarding transport, can you build a simple sled and tow it behind a 4 wheeler or side-by-side?

[TreefarmerNN]

I am in western North Carolina in the blue ridge mountains. We are building hiker bridges. The trails are generally less than 10% slope except for short sections. In addition to Hand carrying we sometimes use a tracked carrier and sometimes use a big wheel hand truck. We attach the board to the hand truck with a ratchet strap with the wheel about 1/3 of the way from the end. The tracked carrier rolls over when there is too much side slope. The hand truck can handle rougher trails, but for my next bridge, the tread is too bad for either. I am 68. Our groups average age is 73.i think my other option is skidding them. I have a portable capstan winch. I mostly use it for moving rock. This stuff is sort of light and fragile to drag with a winch. My other option is to do a bunch of tread work.

KDAT is not readily available around here. You can order it.

It seems sad that you don't have younger people to do the heavy lifting.  It would be good for them to gain the skills and I'm sure y'all wouldn't mind someone else carrying the load.