LumberJocks Woodworking Forum banner

Plywood vs manufactured wood in shop/outdoor furniture

4K views 23 replies 11 participants last post by  rbrjr1 
#1 · (Edited by Moderator)
Noob type, complex question. Feel free to shoot me. But this IS a serious question. I AM new at this, so here goes.

Plywood has more of a "quality build feel" to it than MDF even for shop furniture to me, at least in looks. But is there more to it than just what meets the eye?

I've read up on MDF, OSB, hardboard and other manufactured products in various places. Obviously, workbenches, furniture & cabinets have all been made with both plywood and manufactured products, but other than looks, I am still at of a loss saying that one construction material is more suitable for a purpose than another from a costs-benefits view. Is plywood more structurally sound when placed on end/edge than MDF/OSB? The other way around? How about if it's going to be outside function-over-looks furniture/cabinetry? If it's painted, does MDF/OSB stand up as well as plywood in high humidity environs outside - not directly rained on and not with an edge in "standing water"?

I don't know of any "fine furniture" made of either plywood or manufactured products, but that's not under discussion here, just outside patio/workshop type stuff. (Then again, I admit to being very ignorant on this subject.)

Appreciate any explanation, discussion ya'll might think relevant.

Happy Thanksgiving, btw.
 
See less See more
#2 ·
First of all, for outdoor use, you MUST use a product that is intended fro that, meaning the glue holding it together is waterproof. Most MDF doesn't meet this qualification. What might meet this qualification is floor underlayment-type flakeboard or roofing flakeboard. You must make sure it does. The other caveat is flakeboard with its various oriented wood grains will become rough as a cob when exposed to water, so you must seal the wood surfaces thoroughly with the completed project and keep it sealed.

As to strength, MDF is never as strong as plywood. It is strong enough for use with furniture though. Most of today's manufactured furniture is made with MDF and faced with veneer or some other facing. Making joints with MDF type panels is another problem. You must rely on nothing but glue or some type of metal fastener. You can't make dovetails or any other type of fancy joint. The wood" will crumble or break. You must join flat surface to flat surface.
 
#3 ·
Dear Ignorant, I agree with you about the "quality build feel". It will stand up better outdoors than MDF/OSB. It is also not as heavy and will accept fasteners better. With painted MDF/OSB, paint will wear eventually exposing it to moisture and eventual failure. I have used MDF for indoor projects where a flat surface was needed (ie: a workbench top), but I prefer plywood. The big problem with plywood is the lack of high quality. Good plywood, like Baltic birch, marine plywood and furniture grade plywoods are expensive. I have found a plywood that is fairly reasonable in price that I have found at Home Depot. It is called Arauco ply and is a product made from Radiata pine, a renewable wood thats comes from New Zealand and Chile. It is also known as Monterey pine. Unlike most imported panels, Arauco ply has a face veneer thickness of 1/8", so you won't risk sanding through the face. There is another product called "Appleply", but it is a bit more expensive.
 
#4 ·
Hey, thanks for the tip about Arauco ply at Home Depot. I usually shop at Lowe's as it is closer, but I think I'll wander over to Home Depot for a look.
 
#5 ·
Thanks for the replies. Very educational.

Now for an additional and confounding part of my question/ignorance. I am using wood/wood products which come from pallet re-cycling, well, 99.9% of it. Some of it has been used or left outside for undetermined periods of time, both plywood and MDF/OSB. Should I avoid using the MDF/OSB completely, especially considering the end product will be remaining outdoors, though under carport cover?
 
#6 ·
A judgment call. I would say if the man made material looks like it has been left outside (weathered) for a period of time and it appears not to have disintegrated, It should be able to be used outside. No guarantees though. Wood lumber material should hold up outside. But be aware that the wood used in these pallets, etc. are of the lowest quality wood. That means knots, wild grain, checks, and other flaws. Also, I would expect some of this wood would be prone to warping. Understand you are taking this chance and try to weed out the worst of it before using.
 
#9 ·
theres quite a bit of outdoor furniture constructed that can be classified as fine furniture. OSB is for construction- period.and NOT construction of furniture. MDF,imo, is for ikea type furniture or countertop underlayment.

if you dont want this furniture to last and not look nice when completed, use osb and mdf.
i you want to fight all the way through construction, use osb and mdf.

if ya want it to last, use whats been tried and proven to work good for construction
 
#11 ·
Cabinets made of MDF or OSB (using say 3/4 ish thickness) tend to be heavy. I have one, and only one, I made from 3/4 OSB and it weights a ton. Someone gave it to me, I used it, still regret it. For shop stuff I use what is available at a box. Inside the house, baltic birch.

Outside stuff hold up better if you edge the ends of the ply but you can always caulk edges and paint.
 
#12 ·
I guess I should have stated explicitly that part of the reason for asking is I am using reclaimed/salvaged/pallet wood. I've been lucky enough to harvest plywood, MDF/OSB and lumber. Ultimately, all of my workshop products/furniture will be kept outdoors, though under a carport.

Baltic birch is above my paygrade/outside my wallet's ability. OTOH, I have recently salvaged some 3/4"x36"x41.5" 7-ply plywood which has a near furniture-grade exterior veneer. This is in addition to my previous stash of harvested 1/4, 1/2 and 3/4" 5-9 ply plywood and and 1/2" and 3/4" MDF/OSB of varying quality (mostly just construction grade),

My ultimate goal is to to make/have a couple mobile carts/workbenches that are left outside(under the carport) but usable for at least 3 years without having to remake/repair them every year due to being left outside. If I get lucky, I'll be able to put some cabinets in a tool room off the carport (still negotiating with the landlord).

So, on-edge strength, warping if laid flat (benchtop surface), and resistance to humidity (Deep South/Louisiana Gulf Coast) are considerations behind the question.

Thanks for the very helpful responses thus far.
 
#13 · (Edited by Moderator)
A frame of pallet wood with a inexpensive ply top, then painted will last under a carport for more than 10 years. I have one and have not had issues. Even left it out in the rain a few times as my outside workbench. All of my first benches were scraps from all over. They worked, and in time I upgraded.

I feel ya on the $$ involved for the better stuff. My neighbor often wants something done around his place. Big or small project all that money goes into my slushy fund. Only way I afford it. LOL
 
#14 · (Edited by Moderator)
John

Simple answer, ...go for it.

More detailed answer, if you check out LVL beams you will find they are plywood on its end cased with timber and are structural graded.

So yes plywood is OK for your intended use

A technical answer.

Plywood and OSB have a range of grades, information regarding the grades and their application can be found on the web

If you are interested they should be branded somewhere, If you are lucky enough to get a full sheet!

Plywood for instance look up Tradewood and you will find a PDF on the various grades.

OSB look up Norbord in the UK and there are all the gades relating to OSB.

If you do a search here you will find heaps of plywood furniture especially chairs.

Need to know more? just ask I am full of it!!
 
#16 · (Edited by Moderator)
The hassle we have here in Australia of repurposing wooden pallets is you need to know what they were used for.

Maybe hazardous chemicals were transported on them.
Also our quarantine rules are very strict and they may have been fumigated and still contain residues.

We have to be careful but still use a lot of them for projects at school making planter boxes etc. for herb gardens.

Most of our agricultural machinery is imported and parts come in some really outstand boxes and pallets that we use. Some of these are up to 20 feet long and 4 feet square. They are ply or flakeboard covered and brilliant to use. We always use masks to cut and work with, as they are also fireproof. Off cuts just turn black and wont burn at all.
 
#18 · (Edited by Moderator)
Okay… so, I've got more MDF/OSB than construction-grade plywood and am certainly not going to use the best plywood I have on a lumber rack/plywood cart.

If I use MDF/OSB rather than plywood to make Something like this..., which will reside outside under a carport 24/7 where rain gets blown all the way to the 2 walls and general Deep South humidity is a year-round consideration, will I be "losing" much strength build-integrity-wise? What about if I paint it with some cheap ($0.96 @ Walmart) spray paint to try to "seal" it?
 
#21 ·
MDF isn't nearly as strong, durable or able to hold fasteners as plywood. If I were going to the trouble of making a nice wood storage cart, I would use quality materials to build it. If you want to see the best use of MDF, go to the furniture section at Walmart. Those items are full of it. There is such a thing as exterior MDF but most MDF will swell and fall apart very quickly if it gets wet or even stays in a damp location for any length of time. It doesn't matter whether it's painted. I am just trying to save you from disappointment after building your cart.
 
#22 ·
ArtMann, appreciate the comment and advice. As far as "nice", I guess that's in the eye of the beholder - I'm a beginner and right now I'm going for function over "nice". I need to get my wood out of piles and off the floor/ground.

If I have to use up my current stash of plywood, I will. I won't like it, but I will. I'm just trying not to waste it when I have about 3x as much MSF/OSB.

My goal is to spend no money on wood period. I'm retired and living on limited funds/income. All of my wood comes from salvage/pallet/castoffs. I can re-build something/replace pieces later as I get more "free wood" if I have to - much more likely with MDF/OSB than with plywood I guess.
 
#24 ·
hasn't really been laid out, so here goes:

OSB - structural underlayment used in construction - not optimal for any furniture or workbench/etc.

Plywood - there are as many different types as you can think of, but generally speaking it's a good product to use on furniture and for workbenches/etc. (has some dimensional stability, exposed edges are usually the first to succumb to delamination and warping

MDF - superior product for paint grade finish and countertop underlayments as it is extremely smooth and flat and is dimensionally sound when kept out of the elements. Generally speaking, not for use outside

Solid lumber - generally speaking accepts finish well and is superior for maintaining stability when used in the elements (species and joint construction dependent). Solid lumber is also stronger in almost every way than plywood, OSB or MDF (engineered beams being the exception).

These are GENERAL statements meant to guide your product selection, there are OSB and solid wood products which defy these "rules of thumb"..
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top