Drying/Storing under tarps - what are the risks?

[Pepe_Silvia]

I'm starting the process of transitioning between an old building and building a new building, which necessitates drying and storing my slabs outside.  I'm using tarps to protect them from rain and sun.

What are my biggest risks with air drying under tarps?

I'm still stickering as normal.  Is it just extended drying time, or are there other factors to consider?

I'm almost exclusively selling 2-2.5" thick live edge slabs, so I'm not too concerned about grade.  Biggest concerns would be in the structural quality and shape of the wood - warpage, excessive cracking, and rot.

[Southside]

Are the tarps wrapping down the sides of the stack? If so you run a very good chance of having issues. If they are acting as a rain shed and only on top then make sure you have good air flow between the top layer and the tarp so they don't trap moisture. 

[barbender]

In my experience, the biggest issue with tarps is that they fail every time so something that you worked hard to stack, sticker, and get half dried ends up soaked.

[jimparamedic]

I think old tin works the best for outside stacks

[bluthum]

The old sheet metal tin trick is also my choice.  It's stiff enough to provide some overhang without preventing air movement.

[btulloh]

X2 on the roofing tin.  Easy, quick, simple.  

Since you're going to be buying some from your new building (??) you can use some of that to cover your stacks until you put the roof on.  I usually buy a few extra sheets when I'm buying it so I build up my inventory of extra tin.

[kelLOGg]

I used old 5V galv roofing and vinyl siding. The vinyl I glued together individual panels with PVC cement to make convenient widths. I don't use either any more - I air dry under a shed now.

[moodnacreek]

Don't use rusty tin, been there, done that. Factory,ribbed, painted roofing with no holes in the lows. Tarps are absolute last , they always puddle and sweat.

[Brad_bb]

Tarps can trap moisture if they wrap down.  They can block airflow.  Sun may not be your worst enemy because if the outside greys, who cares?  You still have to flatten them and sand/finish the live edge, right?  You don't want them in direct sun when green because you don't want drying in one spot to occur too quickly and cause uneven drying - which can lead to checking.  Shade is preferable.

[YellowHammer]

Tarps draped down the sides of the stack can trap moisture and really mess a stack up, possbly causing mold, sticker stain, etc. Be careful with them.  

[Ianab]

A "roof" made with a tarp and some scrap wood is pretty safe. Keeps the sun and most of the rain off, and any water that does seep or blow in will soon dry out once the rain stops. If you tarp the whole stack, and water does eventually get in, it's trapped, and then you have all sorts of grief. (Mushroom farm :-\ )

You either need to stack safely in a shed where it won't ever get wet, or think "carport" or "gazebo", with open sides, where the wood can quickly dry again if water does get on it. 

[PA_Walnut]

Tarps can trap moisture if they wrap down.  They can block airflow.  Sun may not be your worst enemy because if the outside greys, who cares?  You still have to flatten them and sand/finish the live edge, right?  You don't want them in direct sun when green because you don't want drying in one spot to occur too quickly and cause uneven drying - which can lead to checking.  Shade is preferable.

@Brad_bb pointed out the use of some kinda roofing material some time ago. I tried it and like it a lot, so long as I make a wood frame for it. Comes in 4' roll and is TOUGH. Benefits are that it's less expensive than metal and a WHOLE lot safer.

Ask me how I know. :( (last year, severely cut my hand with a metal sheet on a pile...trip to ER, 3.5 hour surgery to put nerves and tendons back together and 3 months of therapy). If you deal with metal tins, always wear leather gloves, at a minimum. I was doing a "quick fix" in a rain storm and tried to shortcut. It was a costly, painful and permanent mistake. WEAR GLOVES!! Did I mention to always wear gloves?  :-\

[YellowHammer]

Ouch.  

[Brad_bb]

@Brad_bb pointed out the use of some kinda roofing material some time ago. I tried it and like it a lot, so long as I make a wood frame for it. Comes in 4' roll and is TOUGH. Benefits are that it's less expensive than metal and a WHOLE lot safer.

I used that for a short term case.  We had finished beams on site that we did not want exposed to the sun before the frame raising. All the beams had dunnage spacing them apart. They had enough airflow for short term (2 months Dec & January).  I would NOT recommend this for flat stacked wood.


 

 

 

[PA_Walnut]

All the beams had dunnage spacing them apart. They had enough airflow for short term (2 months Dec & January).  I would NOT recommend this for flat stacked woo

I use it regularly now, just like metal tins...build a frame, attach it to the frame and cover the top (not down the sides). Works as good as the metal and a lot easier/safer to handle. I do not cover the sides, as Brad pictured. Just the tops.

[btulloh]

What's the name of that stuff?

Found it:  https://www.lowes.com/pd/Titanium-48-in-x-250-ft-1000-sq-ft-Polypropylene-Roof-Underlayment/3551166

Looks like a good thing.  Missed this the last time around.

[PA_Walnut]

What's the name of that stuff? Found it:  https://www.lowes.com/pd/Titanium-48-in-x-250-ft-1000-sq-ft-Polypropylene-Roof-Underlayment/3551166 Looks like a good thing.  Missed this the last time around.

That's the stuff. Works great! Amazon has it too.