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Group Classification of Species

The species of wood used to manufacture the plywood panel’s face and back are classified into five groups based on their bending strength and stiffness: group 1 being the strongest and group 5 the weakest.

The species are grouped on the basis of their mechanical properties for bending stiffness and bending strength.  These are the most important properties for many plywood uses including concrete formwork.  (Selecting the right panel type for concrete formwork).

Species are classified in accordance with the ASTM-D2555-06-Standard-Practice-for-Establishing-Clear-Wood-Strength-Values (see Appendix A in US standard PS 1-09). The species groupings are valid only for those grown in the region referenced in this standard.

Group 1 Group 2 Group 3 Group 4 Group 5
North American Species (applicable to trees grown in North America)
Douglas -fira
Larch, Western
Maple, Sugar
Pine, Southern
Douglas- fir a
–Calif. Red
–Pacific  Silver
Maple, Black
Western White
Yellow Poplar
Alder, Red
Birch, Paper
Cedar, Alaska
Fir, Subalpine
Hemlock, Eastern
Maple, Bigleaf
–Western Red
–Black (W.Poplar)
–Eastern White
Other Species
Apitong b,c
Kapur b
Keruing b,c
–Red Lauan
–White Lauan
Mengkulang b
Meranti, Red b,d
Mersawa b
a:   Douglas-fir from trees grown in the states of Washington, Oregon, California, Idaho, Montana, Wyoming and the Canadian provinces of Alberta and British Columbia shall be classed as Group 1. Douglas fir from trees grown in the states of Nevada, Utah, Colorado, Arizona and New Mexico shall be classed as Group 2.
b:   Each of these names represents a trade group of woods consisting of a number of closely related species.
c:   Species from the genus Dipterocarpus marketed collectively: Apitong if originating in the Philippines, Keruing if originating in Malaysia or Indonesia.
d:   Red Meranti shall be limited to species having a specific gravity of 0.41 or more based on green volume and oven dry weight.




APA in Europe Wizard

All Questions OSBPlywood

What is a ‘life cycle stage’ and how do these link to the environmental assessment of whole buildings?

How do core category rules link with environmental product declarations?

Whose responsibility is it to check that wood products being imported into the EU do not originate from illegally sourced timber supplies?

Does the EUTR require mills to provide any extra documentation for customs entry into the European Union?

Must all plywood and OSB panels carry a CE marking?

What is the definition of a construction product under the CPR?

What is a Declaration of Performance referred to under the Construction Products Regulation?

What is the difference between Structural 1 and Exposure 1?

Does structural panel siding have shear values?

What are mould and mildew, and do they compromise the integrity of engineered wood?

The CE-mark on an APA plywood panel means it conforms to European Standards – but which ones?

I want to use a Rated Sheathing panel for flooring/ roofing application, what info do I need to know?

Plywood: Span rating
OSB: Span rating

What extra strength benefits do Structural 1 OSB panels provide over standard Rated Sheathing panels?

Do APA panels give off formaldehyde?

Plywood: Formaldehyde
OSB: Formaldehyde

What is the difference between a touch-sanded panel and sanded panel?

I’d like to know how APA veneer grades match those given in the European standards

How do I correctly gauge the face appearance a plywood Siding panel?

I want to specify an APA panel for concrete formwork – what do I need to know?

Are APA panels tongue and grooved on all four edges?

I am not familiar with the term ‘Sized for Spacing’ – what is its significance?

How are Performance Category and thickness related?

I’d like to know more about a panel’s Span Rating and how it links to thickness.

Plywood: Span rating
OSB: Span rating

What is Span Rating on the APA trademark and why is it important?

Plywood: Span rating
OSB: Span rating

What is the difference between Exposure 1 and Exterior plywood panels? What are their appropriate uses?

What are the main OSB panels likely to be available in Europe?

What are the main plywood panels likely to be available in Europe?

What are the main European standards that I would need to be aware of for OSB panels?

The main standards are: EN 13986 and EN 300

What are the main European standards that I would need to be aware of for plywood panels?

The main standards are: EN 13986, EN 636, EN 314, EN 635-3