Outdoor lumber for kids to play on

[midnight armadillo]

I have some questions for all you DIY, outdoors types. I am designing a sandbox and play structure for my little kids. What's the opinion on the ACQ (ammonia copper quaternary) pressure treated wood as far as safety goes? I'd seal it and not leave the wood bare.

I'm thinking of just using good quality pine, sealed with polyurethane or something, for the sandbox. I'd like to use plastic lumber but it's too pricey. Any thoughts on how long this would last in New England? In 10 years the boys will have outgrown a sandbox anyway.

For vertical, in-ground posts I'm calling lumber yards looking for black locust but no luck so far, so I may be forced to use the ACQ for 4x4's. Thanks!

[Adsos Letter]

1. Re; the pine

Well, we're on different sides of the continent so our wood choices may vary; however, here in California we use a lot of Redwood for outdoor structures because of it's natural resistance to bugs and rot. Apply a clear (or tinted) stain/sealer and it will go the distance. I have Redwood planting boxes which have done very well over the last 15 years.

We rarely use pine for exterior applications because it doesn't hold up. Douglas Fir, however, will often be used for exterior trim work, trellises, etc. It is cheaper than Redwood, but holds up better than pine.

As far as ACQ goes, the only thing I can think of off the bat is that it is bad for splinters. I don't think the toxicity issue is a problem, especially if you seal it (I'M JUST GUESSING HERE) but remember that even the best exterior clear finish is going to break down within a couple of years.

If you can spring for it I would go with the Redwood.

[SacredCow]

2. I don't think it's a safety issue....

In the sub tropics of Louisiana pressure treated lumber holds up reasonably well, but as a lifelong southerner I have little experience how freeze/thaw cycles affect wood.

As another poster mentioned, redwood might be another (albeit expen$ive) option. Our guest house is sided with redwood and it has held up wonderfully (20+ years). That is, until the squirrels added it to their diet. Now, I'm replacing the eaves at an alarming rate.

[LNM]

3. Not sure about the wood but

if you're building a sandbox for the kiddies make sure you also build a lid for it. Kitties love sandboxes too.

[midnight armadillo]

4. I'm working on a raisable lid

the lid will raise up and become a sunshade...

I'll look into douglas fir for the sides and black locust for the posts. Too bad locust doesn't come in 2x12's.

[Adsos Letter]

5. The fir should work, but it doesn't do nearly as well as Redwood

when you are talking ground contact; however, if you are using 2x12's Redwood IS going to be expensive. You might check out Cedar, as it has some excellent natural properties. I don't know the properties of Black Locust, as we don't use it out here, so I can't comment to that.

I would, however, think that the "pressure-treated" material would not carry any safety concerns for the 4x4 (or 6x6) posts you are going to use. They are manufactured specifically to overcome the problems with ground contact.

I would be sure to "treat" all of the material, especially the ground-contact stuff, After you cut for length but BEFORE you install it. Really soak that end grain of your cuts, until it won't absorb any more.

Good Luck! Post a picture when you're done.

:D

[jmowreader]

6. What I know about ACQ lumber in this case...

It's safe to use for children's play structures.

In the OLD days--say, before 2004--CCA lumber was what we had. It contained copper, chromium and arsenic. The arsenic got all thebad press, but the chromium was what was really bad for you.

These days, you can run into one of three treatments:

ACQ: Alkaline Copper Quaternary (or Ammoniacal Copper Quaternary--same thing) contains copper oxide, quaternium 60 and sodium carbonate. Copper oxide is basically edible, quaternium 60 is perfectly safe for skin contact (it's the most common preservative found in cosmetics--I figure if you can put the stuff on your face, at a higher concentration than you'd see in lumber, and leave it there for fifteen or sixteen hours like you do if you wear makeup, it's okay to put your hand on it for a little while), and there's not much sodium carbonate in the soup--it's there just to adjust pH levels.

CA/CBA: Copper Boric Azole contains copper oxide, boric acid and tebuconazole. Boric acid is used as eyewash and tebuconazole is a fungicide used on many food crops.

Micronized Copper Quaternary: This is the pressure-treated lumber that doesn't LOOK like pressure-treated lumber. It's basically ACQ, but the copper is ground finer and doesn't impart the "PT Look" to the wood. Still safe to be around, though. Brand is "ProWood."

Also note: You can use either ACQ, MCQ or CBA when building beds for organic vegetables.

[Shakespeare]

7. Why not go for one of the recycled plastic/lumber composites, like Trex?

There are several brands out there now, in a variety of price ranges. An ex-boyfriend's parents used Trex to construct an elaborate deck on their Cape Cod home, and it's beautiful. Almost indistinguishable from wood, more durable than wood, and a good environmental choice, too.