Building pavilion with untreated, fresh timbers?
I live in central Ohio and plan to build a 20×20 pavilion this summer. I think it will be something like this, although I have not drawn up detailed plans or spoken with the building dept.:
https://www.eshsheds.com/cdn/shop/products/34698-2_1200x1200.jpg?v=1558127203
As I go about planning, I’m wondering if I can use fresh cut, untreated lumber from a local Amish sawmill. The owner said they can make 8×8 posts and 8×14 headers and ridge beam. The posts would be white oak milled to order, so it’s is VERY fresh lumber. Not kiln dried or air dried. The rafters and headers could be oak too, but the owner recommended pine since it’s so much easier to handle (an oak 8x14x22 would weigh about 900 lbs. ?).
I’m asking this since the Amish route is CONSIDERABLY cheaper than the big box stores or online kits. As in less than half the price. My wife’s cousin is a local contractor and often uses their products and vouches for the quality. He introduced me to the owner yesterday.
My question isn’t about engineering specs — that will be settled with the county. I’m just wondering if it’s common or wise to use fresh cut, untreated lumber for a pavilion. I would likely use timber screws and brackets as fasteners. I’d prefer not to do mortise and tenon style if I don’t have to. I know green lumber will shrink some over time, so I would not use it for the roof decking. But could I use it for the posts, headers and 4×6 rafters?
As for weather treatment, I would seal the exposed sides with Borate or something similar and I would likely seal the bottoms of the posts before I bolt them into the brackets that I would “wet set” into concrete pillars.
Any other ideas, tips, concerns, etc. will be greatly appreciated.
Replies
I've had good luck with borate treatments on a number of applications, and think that soaking the bottoms of your posts in a borate solution in a 5 gallon bucket might be effective to get great penetration, along with sealing the bottoms of the posts, as you already mentioned. It might also be beneficial to use borate rods, where you drill a hole, insert a rod, and cap the hole. (I've done this on my log home in areas that have greater exposure to the weather.) Also, staining/sealing the pavilion with a high quality finish should keep the pavilion looking great for quite some time. I've had good results with Cabot Gold as an outdoor finish... I've also used Continental Weatherseal Stain with good results...
Thank you for the feedback!
Using fresh cut lumber can save you a bunch, but there are trade-offs. It might warp or shrink more than kiln-dried wood. Sealing the wood and using the right fasteners can help. Pine could be easier to work with, but if you're up for it, oak could give your pavilion a unique, sturdy look.
Check with the county for safety, and if your wife's cousin vouches for the quality, that's a good sign. Overall, as long as it meets safety standards, using local, untreated lumber could be a smart, cost-effective choice!