Outdoor picnic table with plywood - good idea?

[radhak]

LOML saw this outdoor portable picnic table, and now wants it. As I see it, it's a pretty easy job, and cheap too.

But would the average Oak / Birch plywood sheet from HD/Lowes be good enough for a table that should be out in the open most of the time?

My concern is two-fold : will it have strength, and can it withstand the outdoor weather?

The plan does ask for paint, and I would have no problem with that (after all, its a completely-plywood project), and from whatever I have gathered here, any decent external Latex paint should do....right?

[JR]

I don't see why this wouldn't be a perfectly serviceable project. Particularly if painted.

The difference in using plywood for an outdoor project vs redwood or cedar, is in the way they age. Redwood ages very gracefully, losing very little of its structural integrity and dimensional stability. Plywood, on the other hand, when it eventually starts to age outdoors, will delaminate and start to fall apart.

I'd guess a plywood project like this, properly finished, would last 2-3 years of outdoor use before it started to showed any age, and would probably die at about 5 years. Redwood would start aging immediately, depending on how it was finished, but last more like 10 years. YMMV.

JR

[radhak]

Thanks JR. 2 or 3 years is all I have in mind. By then I'd want to do a real table (right now am pressed for other, greater projects on hand).

The only other option would be cedar, and that would be more effort and money. Redwood, unfortunately, is something I have not seen in FL...

[LCHIEN]

I assume you know the difference between interior ply and exterior ply.
Even painted, I would use the exterior ply and that is not generally available in hardwood finishes like Oak, birch.
The exterior plywood has waterproof glues so it won't delaminate even when the humidity is high. I don't think the paint can keep out the misture forever.

[LarryG]

+1 on using an exterior grade plywood. Most (if not all) of that I've seen has been fir, which takes paint well. There's little reason to use birch or, especially, oak if you're going to apply an opaque finish.

I'd also recommend applying wood banding at all edges, to help keep the moisture out. Unprotected edges is where plywood is most vulnerable. It'll look better, too.

[radhak]

umm, yeah of course, i know exterior ply - totally....

well,... not really... at least, not before both of yours' posts. i do think i have seen some ply marked 'exterior' in HD, maybe?

and since i don't do anything nowadays before asking here, i did not buy my plywood yet.

Thanks Loring and Larry for that timely reminder. One more 'knowledge point' for me to show off to LOML...

edit : and when you say wood-banding, is that hardwood edge, or would the band strips i see in HD do?

[bmyers]

LOMLs father built one. It's outlasted him so far, maybe me too. Exterior ply of course. He just sealed it with clear poly. The kids love it. It makes even a picnic in the back yard "official".

It's at least 25 years old. Some of the veneer ply is peeling but still usable. I plan to fill/sand and reseal. It's a similar design be I think it came from a 70's Home&Garden or something.

Bill

[LarryG]

Almost any kind of banding, really, but here's the gotcha ... it needs to be glued on really well, so that the plywood and the banding essentially become one piece. A generous application of waterproof glue (Titebond III or similar) will accomplish this. You don't want water to be able to wick in between the banding and the plywood and get trapped there. That would be a worse situation than just leaving the edges "naked."

If you wanted to get semi-fancy, you could use a wider piece that's offset toward the bottom, to give the top more visual mass, stiffen the plywood's edge, and create a drip for water. Like so:

[LCHIEN]

well, i wasn't sure you knew about Exterior grade Ply when you mentioned Oak and birch. But i was almost afraid to mention it.

A classic table made from treated pine might not be much more expensive than plywood and possibly sturdier. It won't be portable but if your intention is to leave it in the backyard year-around then it will probably last 10 years. I'ms sure if you look there will be some plans on the net for simple ones. It'll be about at least 33% cheaper than cedar and much, much less than the cost of redwood, probably.

[JR]

The only other option would be cedar, and that would be more effort and money. Redwood, unfortunately, is something I have not seen in FL...

LOL! I saw cedar at the hardwood store yesterday, and it can be found around here in hobby packs for lining closets and such.

OTOH, there are stacks and stacks and stacks of redwood at HD. Dog-eared fence boards. 4x4 fence posts. 2-by construction-grade stuff. Clear redwood in ~5/8" dimension. I made a glorous deck once (actually my brother made it and I paid) from clear redwood 2-by. I've got a garden bench, a plant bench, a rolling pot holder, a patio cart, small table, all made of redwood. Can't turn around without tripping on the stuff around here.

JR

[SARGE..g-47]

Afternoon radhak...

"The only other option would be cedar, and that would be more effort and money. Redwood, unfortunately, is something I have not seen in Fl"... rh

Have you ever seen any "marine plywood" in Florida.. bet ya have or if ya haven't.. you won't have break a sweat searching before you stumble over it!

Regards...

[radhak]

Afternoon radhak...

Have you ever seen any "marine plywood" in Florida.. bet ya have or if ya haven't.. you won't have break a sweat searching before you stumble over it!
Regards...

Yes, I have heard of it - but isn't it mega-expensive? And also very fancy?

[SARGE..g-47]

Evening Rad...

I'm not sure what the going price is these days. I lived in Tampa 6 years back in the 70's when I worked for Anheiser Busch and I'm sure it has gone up since then. Just call and ask. I personally feel that plywood has gone way to high also for what you're getting.

The marine ply would be a good outdoor solution, but if you are running on a tight budget... may I suggest that you price "cypress" which is abundant in Florida. I have seen cypress fence post sunk in water that may still be around as far as I know. Barns also that were over 100 years old without any finish and they still standing tall. It's an excellent outdoor choice and far below cedar in price.

Good luck in your search....

[jackellis]

Cypress probably is a better choice for Florida. For one thing, it's native.

Redwood is amazing stuff. We've had the same redwood picnic set up at Lake Tahoe (elev 6000) for as long as I can remember. At that altitude, UV is really hard on everything, including rock! The set was starting to look crappy four years ago when we were preparing the place for our wedding so I slathered on some new redwood stain and it looks almost new.


If you do decide to use plywood, a thick polyurethane finish should keep out moisture.

[Slik Geek]

I made several tables of a similar design some years ago for youth camping. (We took them apart for transportation). They are surprisingly sturdy. I want to say that it was 1/2" plywood that I used.

I've also built reindeer for Christmas decoration displays using a similar "knock-down" technique. They are painted and stay out during much of our Northern Illinois winters (snow, sleet, rain). When we bring them in during late winter, they have to dry indoors for awhile before then will come apart. (I used exterior grade plywood).