Storing hewn timbers

[Woodland Dave]

Hi everyone,

New member here just getting into timber framing. I've been perusing the forums for a while and have been really impressed with the community's knowledge.

I'm planning on building a 20x20 small house/cabin and have been hewing timbers for the frame. Because it takes so long to process wood this way I won't be cutting any joints till at least next year. I don't even have an engineered plan yet so preparing timbers before knowing what sizes are needed is a little risky but because of the simplicity of my design I feel reasonably confident in proceeding with the hewing. The reason I'm going about things this way is because money's really tight but I still want to work towards my goals. Right now I have some time, a chainsaw and an axe, so I may as well stay busy hewing.

My question concerns storing the timbers while I get everything else in order. All the timbers so far are 8x8 posts of box heart ash from 9 to 11 feet long. My plan is to seal the ends, get them off the ground at least a foot, sticker them level and put a tarp over it. I have nowhere to store them inside. Does this sound like an effective strategy for storing the timbers? I also want to know if there's anything else I should account for because some timbers will be totally green and others partially seasoned. Like if shrinkage in the complete frame doesn't occur the same because some have already shrunk in storage.

Thanks for reading!
Dave

Here's what I got so far. First one I did was pretty rough but the next five came out pretty good. They still need some adze work to clean them up and probably a little scrub planing.



 

 

[rjwoelk]

Dont tarp will cause mold issues put some thing on top to shed water and leave the sides open to let the air blow through.

[Woodland Dave]

Ok. I don't think I have anything else to put on top to shed rain water. Based on your advice I'll have the tarp positioned a few inches above the timbers and I won't wrap the sides. Maybe I can support it with pallets so it doesn't sag anywhere.

[btulloh]

It would be a shame to do all that work and not set up some proper storage.

Pick up a few sheets of tin or build some frames with a little slope and cover with felt or tyvek. You could even make a small temporary structure with a few uprights and a shed roof. Small, low. Just big enough to cover the timbers. It would take less time than hewing one beam and protect your investment.

[Mad Professor]

Plastic corragated roofing on the top works well.  You can put that on top of stickers a little wider than the pile.  Weight down with some scrap pieces so it don't blow off in wind.

Besides end coating you might also want to give them a borax spray to keep bugs out.

[Brad_bb]

No tarp, as other have said, tin or plastic corrugated.  Only use the pastic if your stack is out of the wind.  I've used it and if it can flap in strong wind, it will fatigue and break.  I also suggest you build a 2x4 frame that will allow air between the timber and cover.  I have used cheap ratchet straps to hold it down on the stack.  You can buy the cheap ones (500LB) in packs of 8 or more sometimes.  

In temps above 65F, if your timbers are green at all, consider spraying them with timbor or solubor to keep bugs out.  There are two types of larvae that will attach your wood, those that go after green wood, and powder post beetle (aka PPB) larvae which go after dry wood. If temps are below 65 (not scientific, just my estimate) like in late fall until spring, your wood will dry enough that the green wood larvae won't bother it anymore.  PPB will go after dry wood when its warm enough.  The good thing is that they can be slow to do damage.  They create the tiny pin holes that are a bit under 1/16th inch.  If you get a bad infestation they could do more damage, but many barns have stood for 100+ years without PPB doing enough damage to compromise them.  You can stop their cycle in a couple ways - treate with a borate like those above, or a more penetrating version like Permachink's Shellguard which uses an alcohol solvent to penetrate the wood more.  FYI using Shellguard will require you to wash the timbers with log wash before you can apply a finish.  You can't finish with oil or film over the shellguard.  Even after washing the surface you'll still have protection as it does penetrate a timber a bit.  
   I wouldn't go crazy with Shellguard unless you see signs of significant infestation. I've got Ash beams that have been sitting outside 2 years with no significant issues.  You might want to conside the use of Shellguard on the outside of the cabin, then wash it, then finsh it for long term protection. The other way to get rid of PPB is to apply a film finish on the wood.  For example I used barnwood for window and door trim in my shop.  I put a clear flat urethane finish on the wood.  Any larvae in the wood will eventually bore out when at the adult stage, but adult beetles will not lay eggs/larvae on the wood anymore.  The adult needs to taste the start of the wood in order to trigger it to lay.  If they taste a finish, they won't lay.  I've read that it can take larvae a year outdoors to complete their stage and become an adult, and 2-5 years in indoor conditions.  Not sure why that is.c

[Woodland Dave]

Thanks for the responses everyone. I'll ditch the tarp idea and build a little drying shed from some pallets. I'll figure out something more sturdy for the roof.

Glad I posted this because I didn't give enough thought to the effects bugs would have. I'm leaning towards a borax spray, rather than something like shellguard, because I anticipate having to spray twice while in storage- once now and again after I plane them smooth. The frame will be completely inside the enclosure so I guess, based on Brad's advice, I can apply urethane once everything's standing and dried in.

[Don P]

All shellgard, and bora-care are is DOT (timbor or solubor) with a glycol added. Glycols dry very slowly so allow the borate to penetrate deeper into dry wood. BoraCare uses ethylene glycol (think auto antifreeze), If I remember correctly shellgard uses polyethylene glycol (think thunder jug before a colonoscopy). Another uses propylene glycol, RV antifreeze. Doesn't really matter much which you use or whether you throw in a gallon of one of them in a mix of solubor and water, which is what I do when treating an old cabin or barn, these are simply wetting agents to help the borate penetrate deeper.

I'd also get those timbers up higher, you'll likely be needing block for the build. Also move out far enough that you can mow around the stack, keep the airway open.

[Brad_bb]

I'm sorry, I mistakenly thought it was going to be log wall.  Since a timberframe and will be enclosed, I do not recommend a urethane.  I finish the timberframes with Heritage natural finish - it's an oil comprised of Tung oil, flax oil, pine resin, and other stuff.  It's a good finish and lets the timbers breathe, which they need to do over the years to let their moisture out.  Most timberframes are finished with Heritage oil.  Being that it's inside, that's another layer of protection from PPB.  If I were you, I'd wash the timbers just prior to assembly and when dry, apply the Heritage oil.  

[Woodland Dave]

Thanks Don. So it seems the brand of product or which glycol agent is used isn't so important as long as the borate is getting into the wood. I should have looked into this more before posting but you guys gave me what I needed to know! I'm definitely going to get them off the ground more and cover with some roofing material as others have recommended.

Thanks Brad. Heritage oil it is on the finished frame. No urethane.

[Woodland Dave]

 

 

 

So as everyone recommended I got the timbers up off the ground. As you can see I leveled out a pallet platform and stickered them with some old 2x4s. Stickers are less than 2' apart. I'm a little worried it might settle unevenly but I'll check it for level every week or so. I treated the ends with anchor seal. I was late doing this so some slight checks are forming. Next piece I'll seal it asap. I got real lucky finding the scrap roofing for fairly cheap.

Just one more question about the borate treatment: I'm late on getting to this step as well and want to make sure I prepare an effective treatment. Thanks to Don P's reply and other posts I've seen of his I think I understand the process; a powdered borate product in a glycol carrier. For the borate I picked up a 2lb bag of solubor. Tractor supply near me has 1 gallon of propylene glycol for $20 and I figure that will work well. So I'm looking for recipe recommendations. I just want to make sure I get good penetration because I've read ash is more prone to being attacked and the first ones I hewed have been sitting for over 2 months. Also, most people seem to be dipping boards in the solution but my timbers are just too heavy for that. Can a paint brush work? Lastly, when Brad_bb says to wash the timbers does he mean a literal soap and water washing? I got some soil on them when transporting and I plan to just scrub them with a brush and water to get them clean (I have no running water or electric, just rainwater).

[Don P]

That's looking better, do keep plenty of space between the timbers. Whacking the weeds back around the stack will help with airflow as well.

I buy Solubor in 25 lb bags, 2 lbs will make 2 gallons which isn't enough for what you have there. This is not fancy perfume, soak the timbers very thoroughly. At the far end of that spectrum, I kept a thoroughly infested log cabin wet for 30 days spraying it twice a day. Keep the unused portion dry and it will last forever.

Propylene glycol, $20/gallon is steep but watch what you are buying with "pink" RV anti freeze. Some are propylene glycol which is the slow drying glycol you want. Some are ethyl alcohol based, corn liquor, moonshine dries faster than water so this is not what you want, this is the cheapest stuff. Some are a blend, not sure what to advise you there, you'll get some of what you want and some of what doesn't help. The ethyl versions will usually have a combustible warning on them. Sierra auto antifreeze is about 95% propylene glycol at about $14/gallon. Peak -50° RV antifreeze is ~25% PG, their -100° RV antifreeze is about 75% PG, the rest is water in all of those.

The mix is 1 lb of DOT (Solubor or Timbor) per gallon of water for a 10% solution which is typical. You can go up to 1.5 lbs/gal which is a 15% saturated solution and will try to make rock candy or precipitate out if not stirred well and used immediately. Use warm water if available. I use the antifreeze to replace some of the water if I use antifreeze. If the wood is green save your money and omit the antifreeze. I skimp on the glycol, what you are trying to do is make a slow drying solution. Gauge the temp, humidity and direct sunshine on the wood as you decide how much to add. For wood that is barely surface dried like yours, in this cooling weather and out of direct sunshine, a quart per 5 gallon batch would be my first try. By comparison I believe Bora-care as mixed to label instructions would have .5 -2.5 gallons of ethylene glycol in a 5 gallon batch, their ratios run from 9% to 23% DOT in the mix solution.

It helps to add a few drops of dishwashing soap to the batch to help break the surface tension, that helps wet the wood more easily.

A heavy nap roller is much faster than a brush. I usually make 2 very wet passes before flipping the piece, you cannot apply too much. Work over plastic sheeting if you can, it will kill the grass or plants for awhile. It is a soil micronutrient but you are concentrating it in one spot to well over that amount. This is another reason I avoid adding antifreeze if possible, that is not a soil nutrient in any way. You can spray it, I'm not a real fan but better than nothing. Rinse the equipment thoroughly after use, read the rock candy comment earlier, if it crystallizes in your rig its done.

[Woodland Dave]

Thank you Don. I really appreciate the expert feedback. Your instructions were very clear. I guess I have to grab some more solubor. Not sure why I ordered such a small amount. Now I've just got to figure out how much solution to make. I've only got 160 sq. ft. of surface so far and about twice that more left to hew. About how much coverage do you get from a five gallon batch? 

[Don P]

Just going from round about memory of the last batch doing lumber, I think I was getting round about 300 sf per batch.