# Lumber Grades/Quality **URL:** \ **Category:** Factual Questions\ **Created:** [May 27, 2016, 8:03pm UTC](https://boards.straightdope.com/t/lumber-grades-quality/755849 "2016-05-27T20:03:05Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [May 28, 2016, 3:04pm UTC](https://boards.straightdope.com/t/lumber-grades-quality/755849/21 "2016-05-28T15:04:02Z")
> [@John\_Mace](#): > > Do you mean 18 _degrees_ of grade? We have crazy steep lots in some places in CA, and I’ve still never seen a PT deck. Maybe I’m just not noticing… Maybe just the local style? And some of those CA decks on hillsides are scary, not to mention the whole house that might go sliding down the hill if it rains hard. It might not surprise you if you remember the history of stonework here in RI, but stone is replacing wood altogether for a lot of first floor decks, there’s a revival of stone masonry around here. ---
**Author:** ![watchwolf49](https://avatars.discourse-cdn.com/v4/letter/w/e9c0ed/32.png) [@watchwolf49](https://boards.straightdope.com/u/watchwolf49)\ **Post date:** [May 28, 2016, 3:07pm UTC](https://boards.straightdope.com/t/lumber-grades-quality/755849/22 "2016-05-28T15:07:59Z")
> [@John\_Mace](#): > > Do you mean 18 _degrees_ of grade? We have crazy steep lots in some places in CA, and I’ve still never seen a PT deck. Maybe I’m just not noticing… No, 18 inches, as measured from the ground to the boards. > [@TriPolar](#): > > Never heard of that around here, but I never checked either. The inspectors only seem to care about the posts being properly set below the frost line. They never come back after that. New home construction may get more notice. > > Then again, what is the equivalent? If it’s composites and rot resistance woods that pretty much leaves pine-y woods and you’d be crazy to use those now. Here’s a [cite from Rochester, MN](http://www.rochestermn.gov/home/showdocument?id=7679) {PDF}: > [@](#): > > Decks exposed to the weather must be constructed with wood of natural resistance to decay or treated wood. This includes horizontal members such as beams, joists, ledger boards and decking; and vertical members such as posts, poles, guards, handrails and columns. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [May 28, 2016, 3:28pm UTC](https://boards.straightdope.com/t/lumber-grades-quality/755849/23 "2016-05-28T15:28:25Z")
> [@watchwolf49](#): > > Here’s a [cite from Rochester, MN](http://www.rochestermn.gov/home/showdocument?id=7679) {PDF}: So unless they rule out composites that means don’t use really soft wood like pine. ---
**Author:** ![watchwolf49](https://avatars.discourse-cdn.com/v4/letter/w/e9c0ed/32.png) [@watchwolf49](https://boards.straightdope.com/u/watchwolf49)\ **Post date:** [May 28, 2016, 7:04pm UTC](https://boards.straightdope.com/t/lumber-grades-quality/755849/24 "2016-05-28T19:04:37Z")
> [@TriPolar](#): > > So unless they rule out composites that means don’t use really soft wood like pine. Continuing the same cite: > [@](#): > > Other man-made products are subject to approval by the Building Safety Department before use. Building Design/Plans Due to the new Code change, reference should be made to the American Wood Council (AWC) website for drawing aid prior to plan review submission. Sorry I cut that short in my previous post. So, no pine in Rochester, here we can use D-Fir if it’s above 18" from the ground ---
**Author:** ![FluffyBob](https://avatars.discourse-cdn.com/v4/letter/f/ecb155/32.png) [@FluffyBob](https://boards.straightdope.com/u/FluffyBob)\ **Post date:** [May 28, 2016, 8:11pm UTC](https://boards.straightdope.com/t/lumber-grades-quality/755849/25 "2016-05-28T20:11:03Z")
> [@John\_Mace](#): > > Please, guys. “Decking”, not “flooring”. 😉 > > I’ve just never heard of anyone using PT boards for decking. Do you live in some unusual environment? Well, up here in Canada ACQ treated 5/4 decking is extremely common. It is my understanding that treated wood regulations and grades are different than in the States, and all treated wood was switched over to ACQ (can’t recall what the previous formulation was). Quality of material varies and it is often made from Lodgepole pine, so there are plenty of twists and resin pockets to sort out. It is ugly green to begin with but after a couple years fades to a pleasant yellow colour. It stains up nicely if you want it to look like cedar. Only drawback to staining is that you are supposed to let it dry out for 6 weeks first, and if staining decking it is best practice to stain/seal the underside of the decking before laying it. In Calgary here it it is good for 20 to 30 years with a little care. Staining cedar or treated wood only marginally improves its lifespan. I doubt it lasts as long in a wetter climate. Although it is rare now we used to do treated wood foundations (PWF) here. If done properly they have a number of advantages even. I am looking at doing a new deck out back in [Tamarack](http://www.albertacanada.com/business/industries/bp-wood-species.aspx) actually. It is quite strong, fairly rot resistant and weathers out to a very nice silver. ---
**Author:** ![John\_Mace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_mace/32/185_2.png) [@John\_Mace](https://boards.straightdope.com/u/John_Mace)\ **Post date:** [May 28, 2016, 10:27pm UTC](https://boards.straightdope.com/t/lumber-grades-quality/755849/26 "2016-05-28T22:27:56Z")
> [@watchwolf49](#): > > Building codes generally require PT (or equivalent) for any location within 18" of grade. That might be local to the rain forested areas where everything stays dripping wet ten months a year. > [@John\_Mace](#): > > Do you mean 18 _degrees_ of grade? We have crazy steep lots in some places in CA, and I’ve still never seen a PT deck. Maybe I’m just not noticing… > [@watchwolf49](#): > > No, 18 inches, as measured from the ground to the boards. I read your first post as “with 18” of grade". Now I see where my confusion came from. But yeah, I would never recommend a wood like Doug Fir for decking. If you can afford it, Ipe (I mentioned that earlier) is fantastic. You can soak that stuff in water for decades without affecting it. IIRC, you get 5/4 thickness giving you the same strength as 2x decking (net 6/4 thickness). ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [May 28, 2016, 10:42pm UTC](https://boards.straightdope.com/t/lumber-grades-quality/755849/27 "2016-05-28T22:42:26Z")
Ipe is very durable, and insect as well as rot resistant according to the[Wood Database](http://www.wood-database.com/lumber-identification/hardwoods/ipe/). > [@](#): > > Rot Resistance: Rated as very durable; excellent insect resistance, though some species are susceptible to marine borers. Superb weathering characteristics. (Ipe was used for the boardwalk along the beach of New York City’s Coney Island, and was said to have lasted 25 years before it needed to be replaced: an amazing lifespan given the amount of traffic and environmental stresses put upon the wood.) Home builder should note the hardness though: > [@](#): > > Workability: Overall, Ipe is a difficult wood to work, being extremely hard and dense, with high cutting resistance during sawing. Ipe also has a pronounced blunting effect on cutting edges. You’ll need some extra blades for a circular saw or miter saw if you do fancy patterns with it. You may need to pre-drill any nail or screw holes. I’m sure nail guns can penetrate it though. ---
**Author:** ![John\_Mace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_mace/32/185_2.png) [@John\_Mace](https://boards.straightdope.com/u/John_Mace)\ **Post date:** [May 28, 2016, 11:01pm UTC](https://boards.straightdope.com/t/lumber-grades-quality/755849/28 "2016-05-28T23:01:42Z")
> [@TriPolar](#): > > Ipe is very durable, and insect as well as rot resistant according to the[Wood Database](http://www.wood-database.com/lumber-identification/hardwoods/ipe/). > > Home builder should note the hardness though: > You’ll need some extra blades for a circular saw or miter saw if you do fancy patterns with it. You may need to pre-drill any nail or screw holes. I’m sure nail guns can penetrate it though. Yeah, I meant to say something about that. You wouldn’t want to use nails, though. Pre-drill for decking screws, and figure you’re going to eat a bunch of drill bits. ---
**Author:** ![slash2k](https://avatars.discourse-cdn.com/v4/letter/s/439d5e/32.png) [@slash2k](https://boards.straightdope.com/u/slash2k)\ **Post date:** [May 29, 2016, 1:40am UTC](https://boards.straightdope.com/t/lumber-grades-quality/755849/29 "2016-05-29T01:40:44Z")
> [@TriPolar](#): > > You’ll need some extra blades for a circular saw or miter saw if you do fancy patterns with it. You may need to pre-drill any nail or screw holes. I’m sure nail guns can penetrate it though. Ipe dust is also allergenic and toxic, so you’ll need to take [greater precautions](http://www.woodweb.com/knowledge_base/Working_Safely_with_Ipe.html) than you would with for example pine. ---
**Author:** ![FluffyBob](https://avatars.discourse-cdn.com/v4/letter/f/ecb155/32.png) [@FluffyBob](https://boards.straightdope.com/u/FluffyBob)\ **Post date:** [May 29, 2016, 4:28am UTC](https://boards.straightdope.com/t/lumber-grades-quality/755849/30 "2016-05-29T04:28:56Z")
Sounds like an expensive hassle for a deck. There has been a trend for tropical hardwood decking lately but personally I rather go with something I know is sustainable and local. I am sure teak, tigerwood, ipe and all make for a great looking deck, but its just a deck. ---
**Author:** ![wguy123](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wguy123/32/3161_2.png) [@wguy123](https://boards.straightdope.com/u/wguy123)\ **Post date:** [May 29, 2016, 5:50pm UTC](https://boards.straightdope.com/t/lumber-grades-quality/755849/31 "2016-05-29T17:50:47Z")
> [@usedtobe](#): > > Look out for Brown-colored Pressure Treated lumber. > > PT was the one type of lumber I’d buy from HD. There are specs (not much, but it does have to be Kiln Dried (which most of HD is NOT). > > But: > For PT lumber: > > Green = Good for Structural > Brown = for appearance only > > Do not put down brown PT and try to walk on it unless you have really good joists and lots of them. ??? What would a brown PT 2X6 be used for if it cannot be used for structural work? Are folks using this 2X6 for trim and finish carpentry? You have any links that explain how brown is good for appearance only? ---
**Author:** ![Fotheringay-Phipps](https://avatars.discourse-cdn.com/v4/letter/f/d9b06d/32.png) [@Fotheringay-Phipps](https://boards.straightdope.com/u/Fotheringay-Phipps)\ **Post date:** [May 31, 2016, 2:40pm UTC](https://boards.straightdope.com/t/lumber-grades-quality/755849/32 "2016-05-31T14:40:11Z")
> [@John\_Mace](#): > > First of all, why are using pressure treated lumber for your decking (what you call “flooring”)? Pressure treated will be used for posts, stringers or ledgers, sometimes joists. > > “Select” or #1 is used for structural elements like headers. > > You should be able to buy decking that is either cedar or redwood. If you want something a little special, try Ipe. It’s a Brazilian hardwood that is very rot resistant. And it looks beautiful. You pay for it, but it looks really nice. You also pay more for cedar and redwood. If you need something weather-resistant, PT is the cheapest option. by far Having pulled up the old floor (or “decking”, if you prefer) over the weekend I see that the joists underneath are splitting somewhat. (I’m going to have to drill pilot holes for my screws and/or drill them in on an angle.) This deck has survived 20 years, and I’m hoping the new floor/decking will survive the same 20 years, but after that the whole thing is going to need to be replaced. ---
**Author:** ![lance\_strongarm](https://avatars.discourse-cdn.com/v4/letter/l/87869e/32.png) [@lance\_strongarm](https://boards.straightdope.com/u/lance_strongarm)\ **Post date:** [May 31, 2016, 3:19pm UTC](https://boards.straightdope.com/t/lumber-grades-quality/755849/33 "2016-05-31T15:19:14Z")
> [@TriPolar](#): > > He advised rot resistant cedar or redwood, not just pine. And painted pine will last a number of years. What do you think people were doing before Pressure Treated wood was available? They were scraping and repainting their decks every few years. And building them under porches rather than in the open air. ---
**Author:** ![lance\_strongarm](https://avatars.discourse-cdn.com/v4/letter/l/87869e/32.png) [@lance\_strongarm](https://boards.straightdope.com/u/lance_strongarm)\ **Post date:** [May 31, 2016, 3:21pm UTC](https://boards.straightdope.com/t/lumber-grades-quality/755849/34 "2016-05-31T15:21:41Z")
> [@John\_Mace](#): > > Please, guys. “Decking”, not “flooring”. 😉 > > I’ve just never heard of anyone using PT boards for decking. Do you live in some unusual environment? Other than composite, I don’t think I’ve ever gone to Home Depot and seen decking wood that isn’t PT around here (mid-Atlantic). ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [May 31, 2016, 4:04pm UTC](https://boards.straightdope.com/t/lumber-grades-quality/755849/35 "2016-05-31T16:04:24Z")
> [@lance\_strongarm](#): > > Other than composite, I don’t think I’ve ever gone to Home Depot and seen decking wood that isn’t PT around here (mid-Atlantic). I usually go to the Lowes because it’s closer than HD, and they’ll have 5/4 cedar for decking. ---
**Author:** ![lance\_strongarm](https://avatars.discourse-cdn.com/v4/letter/l/87869e/32.png) [@lance\_strongarm](https://boards.straightdope.com/u/lance_strongarm)\ **Post date:** [May 31, 2016, 4:31pm UTC](https://boards.straightdope.com/t/lumber-grades-quality/755849/36 "2016-05-31T16:31:14Z")
> [@TriPolar](#): > > I usually go to the Lowes because it’s closer than HD, and they’ll have 5/4 cedar for decking. Yeah, I have to drive quite a ways past HD to get to Lowes, but it’s often worth the trip. ---
**Author:** ![Ludovic](https://avatars.discourse-cdn.com/v4/letter/l/7ab992/32.png) [@Ludovic](https://boards.straightdope.com/u/Ludovic)\ **Post date:** [May 31, 2016, 7:57pm UTC](https://boards.straightdope.com/t/lumber-grades-quality/755849/37 "2016-05-31T19:57:22Z")
Wait until you see the confusing plethora of choices in moisturizing butter. Because there are fifty grades of shea. ---
**Author:** ![FluffyBob](https://avatars.discourse-cdn.com/v4/letter/f/ecb155/32.png) [@FluffyBob](https://boards.straightdope.com/u/FluffyBob)\ **Post date:** [June 1, 2016, 4:45am UTC](https://boards.straightdope.com/t/lumber-grades-quality/755849/38 "2016-06-01T04:45:25Z")
Golf clap. Funny enough I was asked to do a repair on an Ipe deck Monday. Not easy to find anything that is not milled 5/4 deck material, and even random board stock is no bigger than 2x6. I have to mill up radiused stair runners to match 6" decking, so that is going to be a challenge. The stuff does not glue well (and it is an outdoor application anyway) so I cant laminate material to make a larger blank. Supplier has suggested Santos Mahogany supposedly product that is a near match in appearance and hardness and used for Ipe deck repairs sometimes, but at least available in larger board size. Just as bad to work with as Ipe though; high silica content lung and blade ruining dust. Might buy some sacrificial blades as I do not want to ruin my good blades with such a high silica wood. And some fresh respirator filters. Treated pine or Cedar left to silver sounds better and better. ---
**Author:** ![Fotheringay-Phipps](https://avatars.discourse-cdn.com/v4/letter/f/d9b06d/32.png) [@Fotheringay-Phipps](https://boards.straightdope.com/u/Fotheringay-Phipps)\ **Post date:** [June 15, 2016, 2:10pm UTC](https://boards.straightdope.com/t/lumber-grades-quality/755849/39 "2016-06-15T14:10:21Z")
Having completed the project, there was one thing I hadn’t counted on. The level of shrinkage. The deck is 12’x18’ with the boards running the long way. The original builders had 25 boards extending the 12’ width, and it didn’t occur to me that they wouldn’t fit when replaced. But they didn’t. I jammed them together as much as I could (there were small cracks where the boards were not straight) but there was no way they were going to fit. So I had to cut 1" lengthwise off one layer of boards. But now, after they’ve been sitting out for a week and a half, they’ve shrunk to the point where they would easily have fit without cutting. And I’m thinking had I let them sit out to this point before attaching them, I would not have had to make that cut and would have smaller cracks between each row of boards. But I had no idea they would dry so much so soon. OTOH, on looking into it a bit, I’ve seen where some people say if you allow your boards to dry when not attached, they can get warped. So maybe it’s all for the best. ---
**Author:** ![watchwolf49](https://avatars.discourse-cdn.com/v4/letter/w/e9c0ed/32.png) [@watchwolf49](https://boards.straightdope.com/u/watchwolf49)\ **Post date:** [June 15, 2016, 2:33pm UTC](https://boards.straightdope.com/t/lumber-grades-quality/755849/40 "2016-06-15T14:33:39Z")
First off, congratulations … second, don’t sweat the ripper board … third, time to replace those kitchen cabinets … [Previous page](https://boards.straightdope.com/t/lumber-grades-quality/755849.md?page=1)