Sheet Materials brochure - Covers

Plywood General Information
Plywood is a strong, light weight material. When properly specified and used it will give a very long
service life. The grade and species of veneer have a bearing on performance and durability. Proper
application finishing and edge sealing of boards are essential, especially in exterior applications.
BSEN635, 314 & 636 covers all general purpose plywood, softwood, tropical hardwood, temperate
hardwood etc, also bond types and durability of veneer species.
Glue Types
WBP (weather and boil proof) relates solely to the type and performance of the adhesive glue line,
usually an exterior plywood (not CDX). It is a phenol formaldehyde glue type, which can be seen as
a very dark brown/black colour.
EXT Type 1 Exterior Glue is a Melamine Reinforced Urea Formaldehyde resin, which dries an opaque
white colour.
INT The term is an abbreviation for INTERIOR and refers to the glue bond (which is pale in colour)
performance of the plywood. In some standards the term TYPE 3 or TYPE III is used as
an equivalent.
MR (moisture resistant). In some standards the term TYPE 2 or TYPE II is used. Such boards are
only required to survive full exposure to weather for a few years. Not as durable as WBP.
Durability of Veneer Species
The fact that a plywood employs WBP or exterior glue in its manufacture, does not automatically
imply that it is suitable for long term exterior exposure in its received state. The timber veneers must
be of a durable type.
Many situations of exterior use require that a durable veneer species or preservative treatment
is needed.
e.g. C = Face veneer
D = Balance Veneer
X = Exposure 1
(not exterior)
All sheet sizes are 1220mm x 2440mm
unless otherwise stated.
Special sizes of all Sheet Materials available to order.
Some items subject to availability.
All plywoods (including Marine) need to
be edge sealed for exterior use.
Therefore CDX is not classified as fully Exterior Plywood
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