Modern PT lumber

tphoyt

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I just need to rant about PT lumber.
I’m redoing the decks at my house. I added on to the deck 25 years ago so it had a good run and was due for an update. So far I have been able to reuse all the framing until I got to the part I added on. It’s all rotten. The original deck framing is well over 40 years old and still just fine and the crap I added is gone. This drives me nuts. At work I often pull PT post out of the ground that have been there 50 years or more and they are just like the day they went in. I get why they got rid of the nasty chems that allow this but in this day and age you would think they could come up with a better solution to treat lumber that is still better for the environment. The treatment is only getting worse not better. I find Pt lumber all the time that’s less than 20 years old that’s rotten and it’s not even in ground contact. I have been sealing cut ends for many years to try and make it last longer but it really makes no difference no matter what I use. The old green #10 was great stuff but it’s been off the market for many many years.
Ok I’m done 😂
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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since 2004, they got rid of all the good chemicals in PT lumber because its "bad if you eat it". same year they got rid of arsenic in vinyl for boat seats and arsenic for anti-pinking in seat foam.

my fence I put up in 2018 is rotting from the top down on the posts and the bottom up and the battens and pickets. most started rotting year 2 and the fence pickets are 3" above the ground.
 

alldodge

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My marina had some decking which was down for many years but maybe 10 years ago started replacing it. The new decking didn't last but maybe 3 years. So they ordered some from the east coast which said (employees) had more something but didn't know what. They started replacing some of it this year, so the 5 or 6 years area
 

Jeff J

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I just replaced a top board (treated 2x6) on outdoor steps I built in 2020. Mostly just pulled it off with my hands instead of undoing screws. I should replace a couple more. I will be replacing the entire set within a year and will likely use composite although I am not sure where I will find the money for that.
 

dingbat

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You can still get CCA treated but it’s not for residential work. MCA treat is the next best thing but more expensive.

Other grades that are available are explained here…
 

tphoyt

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In my case I’m on an island and all I can get is whats available. Anything that is a special order comes with a very special delivery price. That’s the price I pay for living on an island I guess so I really can’t complain. The landscape timber here is a better quality are far as rot prevention but its only larger timbers. 6x6 and above.
The dock builder here being in the good stuff by barge and that come at a price but it’s the best way to go and Greenheart pilings are the most commonly used.
They aren’t treated at all and are just a very hard and dense wood that’s very rot resistant. They say up to 75 years. They also run around $35 a foot installed so you pay the price for them a hope you don’t out live them.
 

kd4pbs

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I hear motor oil (both new and used to vary the color) possibly mixed with diesel to vary the shade is a great wood preservative. The wood has to be dry so that it will absorb the oil. I haven't tried this, but the next time I make an outdoor thing out of wood, I'll be applying this method.
 

dingbat

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In my case I’m on an island and all I can get is whats available. Anything that is a special order comes with a very special delivery price.
You will not find it in big box stores, but a large maritime market combined with our proximity to the heart of yellow pine industry, makes it readily available in local lumber yards.
 

Chris1956

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There are several types of pressure treated lumber. The cheapest is rated for above ground use. It has the lowest PT retention level.

Lumber rated for ground contact is more rot resistant, and only a bit more $.

Lumber rated for freshwater docks has more retention, say 10X than ground contact rated lumber.

Lumber rated for saltwater docks has 25X the retention of the ground contact-rated lumber.

So for non-marine use, get the ground contact rated stuff.
 

airshot

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I built my home and a deck back in 1999, at that time the new treated lumber had just come onto the market. I used that for the new deck and also built a temporary dock for my pond, but used regular lumber thinking it would be temporary. The deck on the back of the house has been rotted for about 5 years, waiting for prices to stabilize then get it replaced. The temporary dock is still there, made from regular lumber ! It is showing some soft spots and will need replaced in the near future. Bottom line is.....I paid an extra 25-30% to get the good treated wood and it barely lasted 20 years!!
I used plain ole cheap 2x6 and planks for the dock top and saved all that money, and it is still holding, as is the raft I built out of the same cheap construction lumber....?????
 

dingbat

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I used plain ole cheap 2x6 and planks for the dock top and saved all that money, and it is still holding, as is the raft I built out of the same cheap construction lumber....?????
What kind of wood?
Makes a world of a difference

Our four board fence was installed circa 1985.
Has 6"-8" Southern Pine post (PT) and 5/4 x 6" PT poplar boards.

Had a replace a couple posts out of the 150 or so installed. Just finished replacing the 5/4" Poplar with 5/4" Oak this Spring.
Will see how things hold up.
 

dingbat

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Our 300 year old, hand hewn chestnut log barn is testament to the durability of some hardwoods even w/o PT
 

Chris1956

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Your barn has a roof, right? That keeps most of the water off the chestnut logs, helping them to last, although hardwood is more rot resistant.

My neighbor built his deck with Mahagony. It looked like crap, but didn't rot, at least not yet.
 

alldodge

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Your barn has a roof, right? That keeps most of the water off the chestnut logs, helping them to last, although hardwood is more rot resistant.

My neighbor built his deck with Mahagony. It looked like crap, but didn't rot, at least not yet.
No offense but you must not know the properties of Chestnut. There is no other wood that is more rot, bug, moisture wood resistance ever. Chestnut can be rained on and wet and will keep most of it's properties intact

As before. all the Chestnut is gone
 

dolluper

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Jul 19, 2004
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Cedar is best ...more expensive but worth it.... Do it right once not 3 times with garbage P T
 
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