ISO/TR 12910:2010

TECHNICAL ISO/TR
REPORT 12910
First edition
2010-04-01
Light-frame timber construction —
Comparison of four national design
documents
Construction à ossature légère de bois — Comparaison de quatre
documents nationaux pour la conception

Reference number
©
ISO 2010
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ii © ISO 2010 – All rights reserved

Contents Page
Foreword .v
Introduction.vi
1 Scope.1
2 Document design principles .1
2.1 Basic principles .1
2.2 Compliance through pre-engineered solutions .2
2.3 Design requirements matched to risk level.2
2.4 Relationship to engineering design .3
2.5 Evolving understanding of load-resistance interaction.3
3 Coverage and limitations.3
3.1 General .3
3.2 Definition of light-frame construction .4
3.3 Prescriptive and performance-based approaches.4
3.4 Integration of national code provisions.4
3.5 Scope of structural design .5
3.6 Beyond structural requirements, such as durability .5
4 Loads and load factors .6
4.1 General .6
4.2 Basic design framework and philosophy .6
4.3 Load comparisons.6
5 Material specifications.7
5.1 General .7
5.2 Product standards.7
5.3 Proprietary wood products.7
6 Member design .7
6.1 General .7
6.2 Member vs. system design.8
6.3 Roofs.8
6.4 Walls .9
6.5 Floors.9
7 Lateral load systems design .9
7.1 General .9
7.2 Linking lateral design to analysis models .9
7.3 Load action assumptions .10
7.4 Uplift design.10
7.5 Racking and overturning design .11
7.6 Building plan irregularities.11
7.7 Wall openings .11
7.8 Elevation irregularities.12
8 Connection design .12
8.1 General .12
8.2 Fastener schedules .12
8.3 Proprietary connections .13
9 Other .13
9.1 Miscellaneous .13
9.2 Definitions of terminology.13
Annex A (informative) Comparison chart .15
Bibliography .50

iv © ISO 2010 – All rights reserved

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
In exceptional circumstances, when a technical committee has collected data of a different kind from that
which is normally published as an International Standard (“state of the art”, for example), it may decide by a
simple majority vote of its participating members to publish a Technical Report. A Technical Report is entirely
informative in nature and does not have to be reviewed until the data it provides are considered to be no
longer valid or useful.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO/TR 12910 was prepared by Technical Committee ISO/TC 165, Timber structures.
Introduction
Light-frame timber construction is the dominant construction practice for housing and other types of buildings
in some countries. In these countries, it has gained widespread acceptance due to its many benefits, including
ease of construction, cost-effectiveness, adaptation to energy efficient buildings and proven performance. This
Technical Report is intended to provide an overview of the common elements in existing national structural
design documents on light-frame timber construction.
The comparison chart (see Annex A) is intended to assist in that process. This Technical Report draws
attention to several common themes and identifies some differences in the documents reviewed.

vi © ISO 2010 – All rights reserved

TECHNICAL REPORT ISO/TR 12910:2010(E)

Light-frame timber construction — Comparison of four national
design documents
1 Scope
This Technical Report provides an introduction and synopsis of comparisons among the following four national
1)
design documents on light-frame timber (wood) construction:
a) AS 1684-1 (including AS 1684-1:1999/Amd.1:2002), AS 1684-2 and AS 1684-3;
b) the Engineering guide for wood-frame construction;
c) NZS 3604;
d) the Wood Frame Construction Manual (WFCM) for One- and Two-Family Dwellings (Chapter 1: General
information, Chapter 2: Engineered design and Chapter 3: Prescriptive design).
Each of the four light-frame texts compared in this Technical Report is based on a national timber design
standard that includes provisions for assemblies and systems, which go beyond single-member design
methodology. Other jurisdictions also have similar design documents on light-frame timber construction.
Although not all jurisdictions have design documents on light-frame timber construction, timber design
standards typically address assemblies and systems (See 6.2).
2 Document design principles
2.1 Basic principles
AS 1684-1, AS 1684-2, AS 1684-3, the Engineering guide for wood-frame construction, NZS 3604 and the
Wood Frame Construction Manual each comply with a national code, which defines the higher level building
design principles and conditions that need to be met for light-frame timber buildings, including strength and
serviceability criteria, specified loads and material design performance.
In general, AS 1684-1, AS 1684-2, AS 1684-3, the Engineering guide for wood-frame construction, NZS 3604
and the Wood Frame Construction Manual (design documents) share basic principles related to
demonstrating how light-frame timber construction can comply with structural requirements, particularly how it
can resist high-wind and/or seismic loading conditions and provide additional guidance concerning system
design and construction methods.
At the same time, AS 1684-1, AS 1684-2, AS 1684-3, the Engineering guide for wood-frame construction,
NZS 3604 and the Wood Frame Construction Manual do not all seek to have the same coverage or topics
(see Clause 3). Some deal with housing only, others with housing and small buildings; a few with wood
structural design only and others with other structural components or design aspects of the building. These
differences complicate direct comparisons of the documents on a detailed level.
The following are some observations on general principles found.

1) The terms “wood” and “timber” are used interchangeably in this Technical Report.
ISO/TR 12
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