Page 1 of 2 12 LastLast
Results 1 to 15 of 18

Thread: Pressure treated wood for outdoor bench

  1. #1
    Join Date
    Mar 2014
    Location
    Roanoke, VA
    Posts
    8

    Pressure treated wood for outdoor bench

    Hello,

    I would like to build an outdoor bench, it will always be outside. I'm planning on using the cheapest wood I can find for it.

    My question is, should I look to use pressure treated lumber for all of it, or for just the legs that will be making contact with the ground? Can I use regular lumber for the rest?

  2. #2
    Join Date
    Mar 2016
    Location
    Millstone, NJ
    Posts
    459
    at the price of lumber I would look at Lifetime's tables.
    Otherwise I would at the very least do the legs. Thhe surfaces I would throw helmsmen or something on it

  3. #3
    Join Date
    Nov 2009
    Location
    Alaska
    Posts
    376
    If you've ever had a splinter from pressure treated wood, you'd shy away from building a seat out of it...... Can't imagine getting one in my ass.

    Maybe the brown treated (non-pressure treated) for the seat? Pressure treated for the rest of it.

  4. #4
    Join Date
    Mar 2018
    Location
    Orwell, NY
    Posts
    645
    PT wood is good for rot resistance, if you build with PT legs and use ordinary softwood for the rest in 10 years you'll have just the legs left, like a modern art installation.

  5. #5
    Join Date
    Feb 2003
    Location
    McKean, PA
    Posts
    13,675
    You can use pressure treated lumber for the seat. Round over the exposed corners a bit more than they come from the factory. This outdoor swing was made 7 years ago for my sister and it is still being used outdoors. It does get stored indoors in the winter months. No splinters to date.
    Attached Images Attached Images
    Lee Schierer
    Captain USNR(Ret)

    My advice, comments and suggestions are free, but it costs money to run the site. If you found something of value here please give a little something back by becoming a contributor! Please Contribute

  6. #6
    Quote Originally Posted by Hristo Asenov View Post
    Hello,

    I would like to build an outdoor bench, it will always be outside. I'm planning on using the cheapest wood I can find for it.

    My question is, should I look to use pressure treated lumber for all of it, or for just the legs that will be making contact with the ground? Can I use regular lumber for the rest?
    PT lumber “sweats” for a long time and I wouldn’t expect people sitting on it to accept that chemical exposure, particularly on bare skin.

    Do not spread your wood upon the ground. Does it have to be in dirt contact?

    Try cedar or white oak, they’re not that hard to machine (particularly cedar,) and they age gracefully, IMO. Nothing lasts forever in that situation, or at least without other drawbacks.

    Re the legs, you might consider setting things up so that they can be replaced.
    Last edited by Doug Dawson; 07-29-2021 at 3:52 PM.

  7. #7
    Join Date
    Nov 2009
    Location
    Peoria, IL
    Posts
    2,422
    There is a method to give framing lumber longer life with ground contact. Form around the bottom of the leg, and pour a 1/2" thick cap of epoxy on the end grain. It seals the wood and prevents moisture wicking. Douglas Fir will have much better rot resistance than white wood, but it will certainly need maintenance every other year. Cast concrete legs and last a lifetime.
    Last edited by Richard Coers; 07-29-2021 at 4:38 PM.

  8. #8
    Join Date
    Feb 2003
    Location
    McKean, PA
    Posts
    13,675
    Quote Originally Posted by Doug Dawson View Post
    PT lumber “sweats” for a long time and I wouldn’t expect people sitting on it to accept that chemical exposure, particularly on bare skin.
    According to American International Forest Products: "Yes, pressure-treated wood is safe for use in everything from raised garden beds to children’s playhouses. Before 2003, pressure-treated lumber was often treated with chromated copper arsenate (CCA), a preservative containing some amount of poisonous arsenic. Because small amounts of arsenic can leach out of treated wood, the EPA and the wood industry decided to move away from CCA treated wood to other types of wood preservatives, including Alkaline Copper Quaternary (ACQ) and Propiconazole. "
    Lee Schierer
    Captain USNR(Ret)

    My advice, comments and suggestions are free, but it costs money to run the site. If you found something of value here please give a little something back by becoming a contributor! Please Contribute

  9. #9
    Join Date
    Mar 2003
    Location
    SE PA - Central Bucks County
    Posts
    57,870
    Yes you can use PT. The biggest challenge is that most PT you'll find (especially at the lowest cost) is sopping wet when you buy it. For that reason, there will be some movement over time and generally speaking, you'll need to wait 6 mos to a year before you can put any stain on it (often an opaque exterior stain) so that the wood can dry out enough that the finish will perform reasonably well.
    --

    The most expensive tool is the one you buy "cheaply" and often...

  10. #10
    Join Date
    Feb 2014
    Location
    Lake Gaston, Henrico, NC
    Posts
    5,934
    I keep a supply of pressure treated wood on hand. I let it dry for at least a year, before it gets used. Any time we're shopping for framing lumber, I eye the stacks of 2x 10's, and 12's. It there are clear boards, with straight grain, they go home with us.

    Letting them dry that long not only dries them out good enough to build something out of, but it lets them do what moving they're going to do. Boards 12 feet, and shorter get stored vertically, leaning against a wall. If the stay straight, I know they will. If they move, I mill smaller pieces out of them.

    Choosing pieces wisely will make a very serviceable seat outside.

    This cupola was built with every part (except for the marine Baltic Birch plywood roof sheathing) from this Stache, including all the parts for the sash.

    Even if I'm building a deck, or dock, the treated wood sits here for a good while.

    The railing, and porch floor was built from treated wood that had been stored for at least a year, too. When I was building new houses, I kept bundles of it on stickers for the house I would build the next year. This picture was in the process of reassembling this porch, that I built in 1991, after a small tornado hit that house, I think in 2018.
    Attached Images Attached Images

  11. #11
    Join Date
    Mar 2014
    Location
    Roanoke, VA
    Posts
    8
    great thanks for the info. I guess I will try to snag PT lumber from craigslist.

  12. #12
    Quote Originally Posted by Lee Schierer View Post
    According to American International Forest Products: "Yes, pressure-treated wood is safe for use in everything from raised garden beds to children’s playhouses. Before 2003, pressure-treated lumber was often treated with chromated copper arsenate (CCA), a preservative containing some amount of poisonous arsenic. Because small amounts of arsenic can leach out of treated wood, the EPA and the wood industry decided to move away from CCA treated wood to other types of wood preservatives, including Alkaline Copper Quaternary (ACQ) and Propiconazole. "
    Yes they would say that. It's never been shown that arsenic treated wood leaches out arsenic more than a few inches from the wood, so it's probably safe for the vegetable garden. I have mass quantities of it, from the early 2000's, and it's still clammy to the touch, BTW. Direct contact probably not good. I wear gloves. Doesn't glue, doesn't stain, doesn't finish. Doesn't Rot. God's gift to outdoor structures.

    The more recent copper treated doesn't have nearly the reputation for rot resistance, in my circles. The primary reason for going to that over the arsenic was the protection of the people working with it in milling/construction, breathing the dust etc because some people just _refuse_ to wear masks.... but I digress. :^)

  13. #13
    Quote Originally Posted by Doug Dawson View Post
    ... arsenic treated ...
    Just to be clear, there IS a fairly significant difference between arsenic & arsenate. I'll let y'all giggle to your favorite authority to determine how they differ - - if it matter enough.

  14. #14
    Quote Originally Posted by Malcolm McLeod View Post
    Just to be clear, there IS a fairly significant difference between arsenic & arsenate. I'll let y'all giggle to your favorite authority to determine how they differ - - if it matter enough.
    You know what I meant, and that's what matters. FWIW you could still buy the arsenic treated stuff as recently as 2005 or so at some of the big suppliers. AFAIK, it's only available used now. I'm hanging on to my stash.

  15. #15
    Join Date
    Jan 2008
    Location
    Western Nebraska
    Posts
    4,314
    If you really want it, you can still buy CCA PT, it's still commonly used for pole shed grade boards. You may have to specify that you want it for that purpose. At least that's the way Menards sells it. It's one of a very few options that has a chance to last more than a few years in that role.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •