About Plywood?

Question

Describe two advantages and two disadvantages of plywood over solid timber.

Answer 1

Plywood is stronger. The individual layers of plywood are oriented so the wood grains are not lined up between layers. The crossing of the grain patterns between layers stiffens the plywood and makes it resistant to splitting and cracking.

An advantage to ply wood is that it is wide. Ply wood comes in standard sizes of 4ft x 8ft (and may be ordered in longer lenghts upto 12Ft) This is much wider that regular dimensional lumber. (How many four foot wide trees have you seen?) The large size of ply wood makes it easy and quick to sheath a wall or lay down a floor

Ply wood comes in several grades of surface finish (A to D) where A is the finest finish with no visible knots, is sanded and may be used in furniture (there may even be a veneer coating the A side) D grade is the roughest surface and has little or no sanding , knotts ar visible and may even have fallen out.

X referrs to the glue used and indicates the plywood may be used for exterior usage. Grade CDX is commonly used to sheath a home. Each side has a finish C being a little beter than the hidden D side.

Disadvantage to plywood:

The edges of ply wood are ugly. The cross grain pattern and knott hole voids are easily seen when looking at the cut edge of ply wood. This mean that if plywood is used in furniture or other visible applications the edges will spoil the look. This requires additional labor to hide the edges by laminating a veneer to the edge or mittering the corners or adding a strip of regular wood to the edge to hide the plywood.

Planing a plywood edge especially tough with hand tools, it is difficult because of the cross grain mixed in with the straight grain along the cut. Fine tooth saw blades should be used to avoid splintering along the edges of the saw kerf (cut). Cutting regular wood you can easily RIP cut or CROSS cut using larger tooth faster cutting blades as the single grain pattern of regular wood allows. Plywoods mixed cross grains mean that every cut is BOTH a RIP and CROSS cut so a special fine tooth (slower cutting) blade should be used if fine wood working is being done where splintering and tear out along the cut would spoil the surface finish.

The Size advantage of ply wood is also a disadvantage. It iseasier to carry a small narrow piece of lumber than a full size sheet. Especially up a ladder or to hold in place on a wall when nailing.

Answer 2

Advantages:

(1) cheap to manufacture
(2) strong

Disadvantages
(1) Very heavy
(2) Not all grades are usuable for exterior exposure conditions; and like all wood, must be protected from termites (certain grades if I recall correctly are designed to counter this)

What are you thinking of doing though? Solid timber will typically have a higher bending capacity than plywood, if you're comparing a 4x4 to a plywood sheet oriented to be horizontal. Although you could buy a wooden "glulam" beam which I imagine, would start to shoot off into the very expensive and very unnecessary range.

Answer 3

The two most obvious are cost and cost. Plywood cost less to purchase than the same board foot of lumber and it cost less to in stall than the traditional dimensional lumber.

The disadvantages are more hard to 'see'. Ply wood cannot 'breath' like traditional construction and so moisture is trapped and circulation is reduced. This can cause mold, poor ventilation, and swelling of the panel.
Another disadvantage to plywood may be the hardest to understand, it is somewhat aesthetic, but demanded by customers. Plywood just doesn't look good, so we carpet it, put siding on it, vinyl flooring, etc. This puts the cost sometimes above traditional construction.
One more disadvantage is it is difficult to repair once it has rotted, large sections have to be removed and reinforced to make an ample repair.

Answer 4

material made of layers of wood glued together.
I buy my Plywood From these guys.
JW Anant Agarwal
IPC GROUP
[phone] (Mobile)
Skype: anant009
Email: [e-mail]
[e-mail]
WEBSITE: www.icdgroup.com
www.icdgroup.com
www.icdgroup.com

Answer 5

plywood,cheaper,strong in all directions.

plywood,better looking,better in wet conditions.better surface