SIST-TS CEN/TS 12872:2008
(Main)Wood-based panels - Guidance on the use of load-bearing boards in floors, walls and roofs
Wood-based panels - Guidance on the use of load-bearing boards in floors, walls and roofs
This document gives guidance on the use of wood-based panels in structural applications as structural floor and roof decking on joists or structural wall sheathing on studs in accordance with EN 12871. It provides information on:
? inspection at site;
? transport and delivery;
? handling;
? stacking;
? storage;
? moisture content, conditioning and the effects of moisture;
? cutting and machining;
? selection;
? installation.
Holzwerkstoffe - Leitfaden für die Verwendung von tragenden Platten in Böden, Wänden und Dächern
Panneaux a base de bois - Guide pour l'utilisation des panneaux structurels en planchers, murs et toitures
Lesne plošče - Napotki za uporabo nosilnih plošč za pode, stene in strehe
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST-TS CEN/TS 12872:2008
01-marec-2008
1DGRPHãþD
SIST-TS ENV 12872:2004
/HVQHSORãþH1DSRWNL]DXSRUDERQRVLOQLKSORãþ]DSRGHVWHQHLQVWUHKH
Wood-based panels - Guidance on the use of load-bearing boards in floors, walls and
roofs
Holzwerkstoffe - Leitfaden für die Verwendung von tragenden Platten in Böden, Wänden
und Dächern
Panneaux a base de bois - Guide pour l'utilisation des panneaux structurels en
planchers, murs et toitures
Ta slovenski standard je istoveten z: CEN/TS 12872:2007
ICS:
79.060.01
SIST-TS CEN/TS 12872:2008 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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TECHNICAL SPECIFICATION
CEN/TS 12872
SPÉCIFICATION TECHNIQUE
TECHNISCHE SPEZIFIKATION
August 2007
ICS 79.060.01 Supersedes ENV 12872:2000
English Version
Wood-based panels - Guidance on the use of load-bearing
boards in floors, walls and roofs
Panneaux à base de bois - Guide pour l'utilisation des Holzwerkstoffe - Leitfaden für die Verwendung von
panneaux structurels en planchers, murs et toitures tragenden Platten in Böden, Wänden und Dächern
This Technical Specification (CEN/TS) was approved by CEN on 14 July 2007 for provisional application.
The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to submit their
comments, particularly on the question whether the CEN/TS can be converted into a European Standard.
CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS available
promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in parallel to the CEN/TS)
until the final decision about the possible conversion of the CEN/TS into an EN is reached.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36 B-1050 Brussels
© 2007 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TS 12872:2007: E
worldwide for CEN national Members.
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CEN/TS 12872:2007 (E)
Contents Page
Foreword.3
1 Scope .4
2 Normative references .4
3 Terms and definitions .5
4 Performance requirements .6
5 Inspection at site.6
6 Transport and delivery .6
7 Handling.6
8 Stacking .7
9 Storage.8
10 Moisture content, conditioning and the effects of moisture.8
11 Cutting and machining.10
12 Fixing .11
13 Floors — Selection and installation.12
14 Walls — Selection and installation .15
15 Roofs — Selection and installation.18
Bibliography .24
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CEN/TS 12872:2007 (E)
Foreword
This document (CEN/TS 12872:2007) has been prepared by Technical Committee CEN/TC 112 “Wood-based
panels”, the secretariat of which is held by DIN.
This document supersedes ENV 12872:2000. Compared to ENV 12872:2000 the following changes have
been made:
The deliverability has been changed from ENV to CEN/TS. No technical changes have been made.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to announce this Technical Specification: Austria, Belgium, Bulgaria, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.
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CEN/TS 12872:2007 (E)
1 Scope
This document gives guidance on the use of wood-based panels in structural applications as structural floor
and roof decking on joists or structural wall sheathing on studs in accordance with EN 12871. It provides
information on:
inspection at site;
transport and delivery;
handling;
stacking;
storage;
moisture content, conditioning and the effects of moisture;
cutting and machining;
selection;
installation.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
EN 300, Oriented Strand Boards (OSB) — Definitions, classification and specifications
EN 312, Particleboards — Specifications
EN 622-2, Fibreboards — Specifications — Part 2: Requirements for hardboards
EN 622-3, Fibreboards — Specifications — Part 3: Requirements for medium boards
EN 622-5, Fibreboards — Specifications — Part 5: Requirements for dry process boards (MDF)
EN 634-2, Cement-bonded particleboards — Specifications — Part 2: Requirements for OPC bonded particle-
boards for use in dry, humid and external conditions
EN 636, Plywood — Specifications
EN 12871, Wood-based panels — Performance specifications and requirements for load bearing boards for
use in floors, walls and roofs
EN 1995-1-1:2004, Eurocode 5 — Design of timber structures — Part 1-1: General — Common rules and
rules for buildings
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CEN/TS 12872:2007 (E)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1 Service classes
3.1.1
service class 1
is characterised by a moisture content in the materials corresponding to a temperature of 20 °C and the rela-
tive humidity of the surrounding air only exceeding 65 % for a few weeks per year
[EN 1995-1-1:2004]
3.1.2
service class 2
is characterised by a moisture content in the materials corresponding to a temperature of 20 °C and the rela-
tive humidity of the surrounding air only exceeding 85 % for a few weeks per year
[EN 1995-1-1:2004]
3.1.3
service class 3
climatic conditions leading to higher moisture contents than in service class 2
[EN 1995-1-1:2004]
3.2
structural floor decking
assembly of wood-based panels supported on joists over which the decking spans
NOTE The characteristic of the decking is that it is supported by joists and, when subjected to load, is free to deflect
between the joists.
3.3
structural wall sheathing
wood-based panel capable of providing mechanical resistance to a wall structure
3.4
structural roof decking
assembly of wood-based panels supported on joists over which the roof decking spans
NOTE The characteristic of the decking is that it is supported by joists and, when subjected to load, is free to deflect
between the joists.
3.5
warm roof
roof design in which the panels supported on joists are placed below the insulation
NOTE The panels are considered to be under conditions corresponding to service class 1.
3.6
cold roof
roof design in which the panels and some of the supporting joists are placed above the insulation
NOTE The panels are considered to be under conditions corresponding to service class 2.
3.7
sub floor
structural panel meant to be covered by overlays
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CEN/TS 12872:2007 (E)
4 Performance requirements
The requirements to ensure sufficient margin of safety against failure, damage or excessive deflection are
given in EN 12871.
5 Inspection at site
The following should be checked based on the marking of the panel and/or the manufacturer's documentation
and/or the designers specification:
grade or class according to EN specification standard;
thickness;
service class;
biological durability hazard class;
surface (sanded or un-sanded);
edges (tongue and groove or other type of profile);
joist or stud spacing;
load category;
main load-bearing direction for OSB, plywood and solid wood panels only.
6 Transport and delivery
Panels should be adequately protected by a waterproof covering during transportation. Edges should be well
protected from rain or traffic spray. Edge protection should also be provided to avoid damage by ropes, straps
or other banding. This applies particularly to profiled panels such as tongued and grooved panels.
Panels should be stacked properly to avoid sagging or other distortion, see Clause 8.
If packing includes banding or strapping this should be removed as soon as possible after delivery to prevent
any permanent deformation of the panels. When packs are delivered with edge or face protection panels,
these should be left in place until the pack is required for use.
7 Handling
When lifting, moving and stacking panels, edge protection should also be provided to avoid damage by lifting
ropes and/or forklifts.
When handling pre-finished panels, it is essential to avoid damage or dirt on the finished surfaces.
Pre-finished panels should always be lifted from a stack and never slid.
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CEN/TS 12872:2007 (E)
8 Stacking
Panels should be stacked flat on a level surface with all four edges flush. The ideal base is a close boarded or
slatted pallet.
If this is not possible the panels should be carefully stacked on battens of equal thickness at centres not
exceeding 600 mm as shown in Figure 1.
Intermediate battens are recommended every 15 to 20 panels to allow through ventilation, they shall be
placed directly above those below. The battens should be placed parallel to the short edges across the full
width. Overhang of the panels at the ends of the stack should not exceed 150 mm. Where stacks are placed
on top of one another, the bearers should line up vertically to prevent distortion.
The top of the stack should be covered.
Stacking on edge should be avoided whenever possible. Where space will only permit edge stacking then the
edges should not be permitted to come into direct contact with the floor to avoid possible moisture pick-up or
damage to the edges. Panels should not be leant against walls but supported by a braced, purpose made rack
using thick (> 18 mm) base and back panels (see Figure 2).
In case of tongued and grooved panels, edge stacking on the tongue should be avoided.
Dimensions in millimetres
CORRECT
INCORRECT
Figure 1 — Panel storage
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CEN/TS 12872:2007 (E)
Figure 2 — Correct method of edge stacking
9 Storage
Panels should preferably be stored in an enclosed dry building. Where temporary storage outside cannot be
avoided, then stacks should be covered with waterproof but vapour permeable sheeting, keeping all panels on
raised bearers to prevent contact with the ground, water or vegetation. Any protective wrapping should be
kept in place as long as possible prior to conditioning for use.
10 Moisture content, conditioning and the effects of moisture
10.1 Moisture content
Moisture content of wood-based panel products varies in accordance with the moisture condition of the
surrounding environment, and is affected primarily by the relative humidity (rh) of the surrounding air. It moves
towards and maintains an equilibrium moisture content (emc) i.e. one that is in equilibrium with the
surrounding air. This means that moisture contents in wood-based panel products will vary depending on the
situation of use and with time as temperature and humidity conditions change.
Although it is not possible to give precise levels, the figures in Table 1 give a general indication of the range of
moisture contents in wood-based panels in various conditions.
Table 1 — Equilibrium moisture content and conditions of use
Normal range of
Service Approximate equilibrium
relative humidity (rh) Conditions of use
class moisture content (emc)
at 20 °C
1 30 % to 65 % Dry installations, no risk of wetting
4 % ≤ emc ≤ 11 %
in service
2 65 % to 85 % Risk of wetting during installation
11 % ≤ emc ≤ 17 %
and risk of occasional wetting in
service
3 > 85 % emc > 17 % Risk of regular wetting in service
The moisture content of panels when they leave the factory can be as low as 2 % depending on the type of
panel.
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CEN/TS 12872:2007 (E)
This indicates that unconditioned newly manufactured panels can increase in moisture content when installed
in a building under construction and subsequently change in moisture content as the building is occupied,
heated and dries out, with the consequence of dimensional changes, see ranges given in 10.2.
10.2 Dimensional movement
Timber and wood-based panels expand on taking up moisture from the surrounding air, and shrink on losing
moisture. Excessive changes in moisture content may therefore lead to unacceptable dimensional changes
which may result in bowing, buckling or open joints between panels.
Panels should be protected from rain, dampness and accidental wetting and prior to fixing be conditioned to
the moisture content corresponding to the moisture conditions of end use.
Problems which may occur if insufficient care is taken with protection or conditioning include edge swelling
due to moisture ingress at unprotected edges, localised swelling due to moisture pick-up from adjacent
materials which have a higher moisture content, e.g. timber joists, and general expansion causing bowing
between supports or restraints. Any increase in moisture content will cause slight expansion in the panel.
For guidance purposes it may be assumed that a 1 % change in panel moisture content will cause a dimen-
sional change in panel width, length and thickness as given in Table 2.
The dimensional movement of specific products can differ from those given in Table 2 and reference should
be made to the manufacturers, where this is critical.
Table 2 — Dimensional change for a 1 % change in panel moisture content
Dimensional change at 1 % change in
Type of panel Specification panel moisture content
Length % Width % Thickness %
EN 312, P4, P6 0,05 0,05 0,7
Particleboards
EN 312, P5, P7 0,03 0,04 0,5
EN 300, OSB/2 0,03 0,04 0,7
OSB
EN 300, OSB/3, OSB/4 0,02 0,03 0,5
EN 622-2 (Hard) 0,03 0,03 0,5
Fibreboards EN 622-3 (Medium) 0,04 0,04 0,7
EN 622-5 (MDF) 0,05 0,05 0,7
EN 636 (Spruce or 0,015 0,015 0,2
pine)
Plywood
EN 636 (Beech) 0,025 0,025 0,3
Cement-bonded particle- EN 634-2 0,05 0,05 0,04
boards
10.3 Conditioning
To reduce dimensional changes the panels should be conditioned in the service class for the intended end use
by loose laying (for example on floors) or stacking with spacers as appropriate (see Figure 3).
The length of time allowed for conditioning will vary depending on the panel and the likely condition of use. A
minimum period of one week is recommended but a longer period can be necessary.
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CEN/TS 12872:2007 (E)
Figure 3 — Panels stacked with battens
11 Cutting and machining
11.1 General
Wood-based panels can be sawn, routed, spindle-moulded or drilled. When cutting wood based panels it is
important to pay attention to normal good practice e.g. sharp cutters, adequate support close to saws and
cutters, elimination of machine vibration, correct allowance for saw kerf.
The rate of feed should generally be slower than that used for solid wood and cutting tools should be kept
sharp.
The quality of the machined surface decreases with increasing moisture content. When a very close tolerance
fir is needed, panels should be cut to size after conditioning to the moisture content appropriate to the end
use.
11.2 Cutting with hand tools
All panel types can be cut to size with conventional hand tools, however, quicker and more consistent results
can be achieved using either portable or fixed power tools.
11.3 Machining with power tools
Carbide or diamond tipped blades and cutters should be used because of their longer cutting life.
For fibreboards and particleboards saw blades with cross cutting teeth should be used.
Circular saw blades should be set as low as possible to prevent chipping and scoring as the panel passes the
re
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