No. of Plies & Thickness Of Commercial Plywood

Veneer Plies in a Plywood Sheet

Customers usually ask what is the Number of Plies in a plywood sheet . This is a common question.This time let’s talk about the number of plies in a plywood .

The Relationship between Plywood Layers and Quality / Costs

Plywood consist of some veneer plies or layers . The number of ply will affect the production costs and plywood quality.  If the number of plies/layers is more, the plywood will be stronger and the production costs will be higher .  This conclusion is correct only under defined conditions. For example, it may wrong if you simply say a 7-ply-18mm “hardwood plywood” is cheaper than a 13-ply-18mm “poplar plywood”. Because hardwood veneers are more expensive . The 7-ply-18mm hardwood plywood may be more expensive than the 13-ply-18mm poplar plywood .

Number of Plies/Layers in Plywood:

List of Number of Plies/Layers for plywood in each thickness:

Thickness (mm)	No. of Plies of Commercial Plywood
2~3.2	3
3.6	3 or 5
4	5
5.2~6.5	5 or 7
9	7 or 9
12	9 or 11
15	11 or 13
18	13 or 15
21	15 or 17
24	17 or 19
27	19 or 21

Minimum Number of Plies in Plywood

As shown in the table, the minimum number of plies in plywood is 3 plies. An odd number of plies in plywood can reduce warping and deformation . Plywood with 1 ply and 2 plies will warp and twist .

The Laws of No. of Plies in a Plywood

1. If the thickness of plywood increase 3mm, the No. of Plies will increase 2 plies;

2. The plywood made of more plies is stronger than the plywood of same thickness but made of less plies. For example, 18mm plywood of 15 plies is stronger than 18mm plywood of 13 plies.

3. The plywood made of more plies is more expensive than the plywood of same thickness but made of less plies. For example, 6.5mm plywood of 7 plies is more expensive than 6.5mm plywood of 5 plies. Because if No. of Plies is more, more glue will be used and the labor costs will rise accordingly .

If the plywoods’ thickness are the same , usually plywood of more plies are of premium quality .