Concrete Form
Coastal produces concrete form as defined in US Product Standard PS1-09 for Construction and Industrial Plywood. We produce BB Grade Oiled and Edge-Sealed (BBOES) Plyform Class 1 made with 100% Group 1 Southern Yellow Pine veneers. Our BB Plyform is fully sanded on both sides and factory treated with a high quality release agent. Also it is edge-sealed to protect it from water absorption while the concrete is curing. The glue bond classification of our Plyform panels is Exterior.
Note: We highly recommend that Plyform be used as soon as possible after manufacture since the release agent becomes less effective over time. The number of times a piece of Plyform may be re-used usually increases with the “freshness” of the release agent.
Download Concrete Form Spec Sheet 
| Production Item | Performance Category | #Plys | Pcs/Unit | Construction Layup | Notes |
| BB Grade Class 1, Exterior | 19/32 23/32 |
5 5 |
56 46 |
B face, B back C or better inner plies |
Oiled & Edge-sealed |
RECOMMENDED MAXIMUM PRESSURES ON PLYFORM CLASS I (psf) (a) (c)
FACE GRAIN ACROSS SUPPORTS (b)
| Support Spacing (in.) | Plywood Performance Category | Plywood Performance Category | Plywood Performance Category | Plywood Performance Category |
| 19/32 | 19/32 | 23/32 | 23/32 | |
| 4 | 3110 | 3110 | 4010 | 4010 |
| 8 | 1195 | 1195 | 1540 | 1540 |
| 12 | 540 | 540 | 695 | 695 |
| 16 | 245 | 305 | 345 | 390 |
| 20 | 145 | 190 | 210 | 270 |
| 24 | – | 100 | 110 | 145 |
| 32 | – | – | – | – |
(a) Deflection limited to 1/360th of the span, 1/270th where shaded.
(b) Plywood continuous across two or more spans.
(c) ACI recommends a minimum lateral design pressure of 600 Cw but it need not exceed p=wh.
RECOMMENDED MAXIMUM PRESSURES ON PLYFORM CLASS I (psf) (a) (c)
FACE GRAIN PARALLEL TO SUPPORTS (b)
| Support Spacing (in.) | Plywood Performance Category | Plywood Performance Category | Plywood Performance Category | Plywood Performance Category |
| 19/32 | 19/32 | 23/32 | 23/32 | |
| 4 | 1620 | 1620 | 2170 | 2170 |
| 8 | 530 | 530 | 835 | 835 |
| 12 | 165 | 225 | 375 | 400 |
| 16 | – | – | 160 | 215 |
| 20 | – | – | 115 | 125 |
| 24 | – | – | – | – |
(a) Deflection limited to 1/360th of the span, 1/270th where shaded.
(b) Plywood continuous across two or more spans.
(c) ACI recommends a minimum lateral design pressure of 600 Cw but it need not exceed p=wh.
RECOMMENDED MAXIMUM PRESSURES ON STRUCTURAL I PLYFORM (psf) (a) (c)
FACE GRAIN ACROSS SUPPORTS (b)
| Support Spacing (in.) | Plywood Performance Category | Plywood Performance Category | Plywood Performance Category | Plywood Performance Category |
| 19/32 | 19/32 | 23/32 | 23/32 | |
| 4 | 4110 | 4110 | 5005 | 5005 |
| 8 | 1225 | 1225 | 1590 | 1590 |
| 12 | 545 | 545 | 705 | 705 |
| 16 | 245 | 305 | 350 | 400 |
| 20 | 145 | 190 | 210 | 275 |
| 24 | – | 100 | 110 | 150 |
| 32 | – | – | – | – |
(a) Deflection limited to 1/360th of the span, 1/270th where shaded.
(b) Plywood continuous across two or more spans.
(c) ACI recommends a minimum lateral design pressure of 600 Cw but it need not exceed p=wh.
RECOMMENDED MAXIMUM PRESSURES ON STRUCTURAL 1 PLYFORM (psf) (a) (c)
FACE GRAIN PARALLEL TO SUPPORTS (b)
| Support Spacing (in.) | Plywood Performance Category | Plywood Performance Category | Plywood Performance Category | Plywood Performance Category |
| 19/32 | 19/32 | 23/32 | 23/32 | |
| 4 | 2300 | 2300 | 3095 | 3095 |
| 8 | 640 | 720 | 1190 | 1190 |
| 12 | 195 | 260 | 440 | 545 |
| 16 | – | 110 | 190 | 255 |
| 20 | – | – | 135 | 170 |
| 24 | – | – | – | – |
(a) Deflection limited to 1/360th of the span, 1/270th where shaded.
(b) Plywood continuous across two or more spans.
(c) ACI recommends a minimum lateral design pressure of 600 Cw but it need not exceed p=wh.
SECTION PROPERTIES FOR PLYFORM CLASS 1 AND STRUCTURAL 1 PLYFORM (a)
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Properties for Stress Applied Parallel with Face Grain |
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| Plywood Performance Category | Approx. Weight (psf) | Moment of Inertia 1 (in. 3/ft) | Effective Section Modulus KS (in. 2/ft) | Rolling Shear Constant lb/Q (in. 2/ft) | ‘Moment of Inertia 1 (in. 3/ft) | Effective Section Modulus KS (in. 2/ft) | Rolling Shear Constant lb/Q (in. 2/ft) |
| CLASS 1 | |||||||
| 19/32 | 1.7 | 0.115 | 0.335 | 5.438 | 0.029 | 0.146 | 2.834 |
| 23/32 | 2.1 | 0.18 | 0.43 | 7.009 | 0.072 | 0.247 | 3.798 |
| STRUCTURAL 1 | |||||||
| 19/32 | 1.7 | 0.116 | 0.338 | 5.018 | 0.034 | 0.199 | 2.811 |
| 23/32 | 2.1 | 0.183 | 0.439 | 6.109 | 0.085 | 0.338 | 3.78 |
(a) The section properties presented here are specifically for Plyform, with its special layup restrictions.
CONCRETE PRESSURES FOR COLUMN AND WALL FORMS
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Pressures of Vibrated Concrete (a)(b)(c)
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50oF
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70oF
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Walls
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Walls
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Pour Rate (ft/hr)
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Columns
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To 14′
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15′ and Over
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Columns
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To 14′
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15′ and Over
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|
1
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600
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600
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1070
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600
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600
|
810
|
|
2
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600
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600
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1130
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600
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600
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850
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3
|
690
|
690
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1190
|
600
|
600
|
890
|
|
4
|
870
|
870
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1240
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660
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660
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930
|
|
5
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1050
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1050
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1300
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790
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720
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970
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6
|
1230
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1230
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1350
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920
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920
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1010
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|
7
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1410
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1410
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1410
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1050
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1050
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1050
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|
8
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1590
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1470
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1470
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1180
|
1090
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1090
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|
9
|
1770
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1520
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1520
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1310
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1130
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1130
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10
|
1950
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1580
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1580
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1440
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1170
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1170
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(a) Maximum Pressures need not exceed wh, where w is the unit weight of concrete (lb/ft3), and h is maximum height of pour in feet.
(b) Based on Types I and III cement concrete with density of 150 pcf and 7 inch maximum slump, without additives, and a vibration depth of 4 feet or less.
(c) See pages 17 and 18 of the APA Concrete Forming Guide for additional information on concrete pressures.
See our Policies page for safety and warranty information.