Plywood Thickness and Performance Categories
APA plywood panels have been manufactured in line with the official Performance Category set down by the US standard PS1-19. This specifies the thickness tolerances and performance categories for different plywood grades. To allow for slight variations, it also gives a ‘Performance Label’ measurement, with the minimum and maximum allowable panel thickness.
Panel thickness and span rating need to be considered together.
This technical checklist looks at the main plywood grades for different applications, alongside the appropriate performance categories and span ratings.
Performance data is given on APA trademarked panels. As the US standard only gives measurements in inches, our panel thickness table below gives tolerances in mm for different finishes: Unsanded, Touch-sanded & overlaid panels or Sanded panels.
Technical notes:
- Thickness requirements are based on a panel moisture content of 9% and a tolerance of ±0.016” (1/64”) or ±0.4mm for specified performance categories of 3/4 and less, and ±3% for panels with a Performance Category greater than 3/4.
- Recommended thickness labels for each performance category are less than 9/16 or 3% above the minimum. For Performance Categories greater than or equal to 9/16, the minimum values are those for sanded panels.
|
Performance Category |
Minimum Thickness (in/mm) |
Maximum Thickness (in/mm) |
Official Thickness Label (in) |
|---|---|---|---|
|
1/4 |
0.219 (5.56) |
0.281 (7.14) |
0.225 |
|
11/32 |
0.313 (7.94) |
0.375 (9.53) |
0.322 |
|
3/8 |
0.344 (8.73) |
0.406 (10.32) |
0.354 |
|
7/16 |
0.406 (10.32) |
0.469 (11.91) |
0.418 |
|
15/32 |
0.438 (11.11) |
0.500 (12.70) |
0.451 |
|
1/2 |
0.469 (11.91) |
0.531 (13.49) |
0.483 |
|
19/32 |
0.563 (14.29) |
0.625 (15.88) |
0.578 |
|
5/8 |
0.594 (15.08) |
0.656 (16.67) |
0.609 |
|
23/32 |
0.688 (17.46) |
0.750 (19.05) |
0.703 |
|
3/4 |
0.719 (18.26) |
0.781 (19.84) |
0.734 |
|
13/16 |
0.781 (19.84) |
0.844 (21.43) |
0.788 |
|
7/8 |
0.831 (21.11) |
0.919 (23.34) |
0.849 |
|
1 |
0.950 (24.13) |
1.050 (26.67) |
0.970 |
|
1-1/8 |
1.069 (27.15) |
1.181 (30.00) |
1.091 |
|
1-1/4 |
1.188 (30.16) |
1.313 (33.34) |
1.213 |
|
Performance Category |
Minimum Thickness (in/mm) |
Maximum Thickness (in/mm) |
Official Thickness Label (in) |
|---|---|---|---|
|
1/4 |
0.234 (5.95) |
0.266 (6.75) |
0.234 |
|
11/32 |
0.328 (8.33) |
0.359 (9.13) |
0.328 |
|
3/8 |
0.359 (9.13) |
0.391 (9.92) |
0.359 |
|
7/16 |
0.422 (10.72) |
0.453 (11.51) |
0.422 |
|
15/32 |
0.453 (11.51) |
0.484 (12.30) |
0.453 |
|
1/2 |
0.484 (12.30) |
0.516 (13.10) |
0.484 |
|
19/32 |
0.578 (14.68) |
0.609 (15.48) |
0.578 |
|
5/8 |
0.609 (15.48) |
0.641 (16.27) |
0.609 |
|
23/32 |
0.703 (17.86) |
0.734 (18.65) |
0.703 |
|
3/4 |
0.734 (18.65) |
0.766 (19.45) |
0.734 |
|
13/16 |
0.788 (20.02) |
0.837 (21.26) |
0.788 |
|
7/8 |
0.849 (21.56) |
0.901 (22.89) |
0.849 |
|
1 |
0.970 (24.64) |
1.030 (26.16) |
0.970 |
|
1-1/8 |
1.091 (27.72) |
1.159 (29.43) |
1.091 |
|
1-1/4 |
1.213 (30.80) |
1.288 (32.70) |
1.213 |