National Building Code of Samoa

449 Pages·2017·7.23 MB·English

February 1, 2017

National Building Code
of Samoa
NBC
Acknowledgments
A number of people and organisations have contributed to the successful completion of the National Building Code 2017
update (NBC). The NBC could not have been completed without their cooperation, insight, and experience. We acknowledge
with gratitude the dedication and effort of the following contributers, who under the wisdom and guidance of our Almighty
God, dedicated their time, energy and knowledge throughout the process:
FUNDING PARTNERS
The National Building Code 2017 update is part of: the Economy Wide Adaption to Climate Change Project (EWACC)
Funded by: Global Environment Facility through the: UNDP Multi Country Office in Samoa
Part of the United Nations Development Program
TECHNICAL STEERING COMMITTEE
Government Representatives
The Attorney General
Chief Executive Officer Ministry of Natural Resources and Environment
Chief Executive Officer Ministry of Women, Community and Social Development
Chief Executive Officer Ministry of Educations, Sports and Culture
Chief Executive Officer Ministry of Health
Chief Executive Officer Samoa Water Authority
Chief Executive Officer Land Transport Authority
Chief Executive Officer Electric Power Corporation
Commisioner of Samoa Fire and Emergency Services
General Manager Samoa Land Corporation
General Manager Samoa Housing Corporation
Vice Chancellor National University of Samoa
B
Private Sector Representatives
Institute of Professional Engineers of Samoa
Plumbing
Designtech and Engineering
Plumbers' Association of Samoa
IPA Consultants

Kramer Ausenco
Electricial
OSM Consultants
All Electrical & Construction Co. Ltd.
Tinai Gordon and Associates

Vocational Trainers
Architects
Australia-Pacific Technical College
Stewart Architects
VeS Architects and Associates
Urban Planning and Landscape Architecture
Wavefront Planning and Design (Samoa) Ltd.

Builders
Samoa Builders Association
Ah Liki Construction
Craig Construction Ltd
Fletcher Construction
Qing Dao Construction
SMEC International
Zheng Construction

Building Supplies and Manufacturers
Apia Concrete Products Ltd
Bluebird Lumber and Hardware

Air Conditioning and Refrigeration
Samatic Air Conditioning and Refrigeration
__________________________________________________________
Afamasaga Su’a Pou Onesemo, Chief Executive Officer
Ministry of Works, Transport and Infrastructure (MWTI)
February 1, 2017
C

Table of Contents
A CORE PROVISIONS G SITE SERVICING AND WASTE
A1 Building Functions G1 Piping - Water, Greywater and Waste
A2 Building Groups G2 Wastewater Management
A3 Definitions G3 Water Supply
A4 Abbreviations G4 Electrical Safety
A5 Compliance G5 Fuel Supply
G6 Non-Domestic Liquid and Solid Waste
B STABILITY
H CLIMATE CHANGE ADAPTATION
B1 Structure
B2 Sitework H1 Coastal Protection
B3 Unstable Buildings and Demolition H2 Weathertight Construction
B4 Building Materials H3 Energy Efficiency
B5 Glazing and Windows -Structure and Safety H4 Renewable Energy
H5 Glazing and Windows - Heat Reduction
H6 Greenhouse Gas Emission Reduction
C FIRE PROTECTION H7 Green Roofs
C1 Prevention of Fire Occurring
C2 Fire Spread Reduction J NATURAL DISASTER RESILIENCE
C3 Fire Compartments
C4 Evacuation Route J1 Performance Standards for Structural Support
C5 Fire Resistance J1.A Cyclones and Tropical Storm Resilence
C6 Protection of Service Openings J1.B Tsunami Resilience
C7 Fire Safety Systems - All Buildings J1.C Earthquake Resilience
C8 Fire Safety Systems - Tall Buildings, Atria J1.D Landslip Resilience
and Mezzanines J1.E Bushfire Resilience
D ACCESS
K MINOR STRUCTURES /
MAJOR INFRASTRUCTURE
D1 Accessibility for People with Disabilities
D2 Automated Access
K1 Minor Structures
D3 Egress and Movement
K2 Major Infrastructure
E HAZARDOUS SUBSTANCES
Appendix A
Master List Of Acceptable Solutions
E1 Documentation and Approval
E2 Hazardous Processes
Appendix B
E3 Emergency Planning and Warning Systems
Index
Appendix C
F INTERIOR
Safety Glass
F1 Room Size and Noise Reduction Appendix D
F2 Air Quality, Ventilation and Temperature Thermal Performance Software Criteria and
F3 Wet Area Health and Safety Submission Requirements
F4 Lighting
F5 Finishes on Walls, Ceilings and Floors Appendix E
F6 Food Preparation and Refrigeration Hazardous Substances (Schedule 2 of the Waste
Management Act, 2010)
List of Figures
Preface
Figure A1: Measurement of Distances to the Property Line iii
Table A1: Occupancy Rate Calculations v
Figure A2: Climate Change Adaptation in the NBC vi
Figure A3: Example of How to Use the NBC (for any development project) vii
Section A Core Provisions
Table A2: Building Group Categories A-4
Section B Stability
Table B1.6: Durability Goal for Building Groups B-4
Table B1.B.2: Construction Requirements for Concrete Foundations B-6
Figure B2.A.5: Example of Shoring of Exposed Slopes During Construction B-12
Table B2.B.3: Slope Stabilisation and Erosion Control Techniques B-13
Table B2.D.2: Applicable Legislation, Policy and Procedures for Stormwater Management B-15
Figure B5.C.1: Fall Protection Required B-32
Section C Fire Protection
Table C1: Overview of Applicable Sections in the NBC - Section C C-2
Table C2.A.3: Building Setbacks based on Heat Flux C-11
Figure C2.B.1: Required Fire Safety Standards for Selected Linings, Materials and Assemblies C-12
Table C3.A.1: Maximum Size of Fire Compartments or Atria C-16
Figure C3.F.1: Fire Walls Between Adjoining Units C-19
Table C3.E.1: Distance Between External Walls and Openings in Different Fire Compartments C-22
Figure C3.E.1: Distance Between External Walls and Openings in Different Fire Compartments C-22
Figure C4.I.2: Example of Fire-Isolated Stairway, Smoke Lobby and Fire Isolated Shafts C-31
Table C5.C.1: Construction Type A, B or C According to Building Group and Number of Storeys C-36
Table C5.D.1: FRL Minimums for Building Elements C-37
Table C5.E.1: Minimum FRL of Building Materials and Annexure C-45
Table C5.E.1.1: Reinforcement of Gypsum-Perlite or Gypsum-Vermiculite Plaster Sprayed to Contour C-50
Table C5.G.4: FRLs for Building Elements in Carparks C-52
Table C5.H .1: Increased FRLs for Rooms with a Mezzanine C-53
Figure C5.P.2: Non-Combustible Encroachments Permitted for Building Group 5 C-58
Table C7.A.1: Fire Safety Equipment Requirements per Building Function C-65
Table C7.C.1 Minimum Frequency and Location of Smoke Detectors and Smoke Alarms C-67
Table C7.D.1: Requirement for Compliant Sprinkler Systems per Building Function C-69
Table C7.G1: Fire Hose Reels Required per Building Use C-71
Table C7.J.1: Hydrant and Water Supply Requirements per Building Function C-74
Figure C8.B.4: Combined Water Supply for Hose Reels C-84
Section D Access
Table D1: Section D - Overview of Applicable Sections in the NBC D-2
Table D1.2: Accessible Occupancy Units in Multiple Unit Buildings D-3
Table D1.1: Accessibility Requirements per Building Group D-4
Figure D1.B.5: Exterior Threshold Setback from Access Ramp for a Required Accessible Building D-7
Figure D1.C.7: Accessible Features and Layout in a Sanitary Compartment D-10
Table D2.A.2: Accessible Design Features in Lifts D-12
Figure D2.A.3: Minimum Dimensions for Lift Types D-13
Table D2.A.4: Minimum Lift Size in Health-Care Buildings D-13
Table D2.A.6: Permitted Lift Types with Limitation on Use D-14
Figure D2.B.1: Safety Measures for Automated Access Devices D-16
Figure D3.A.1: Types of Exits and Doors in a Multiple Unit Building D-19
Table D3.A.4: Maximum Travel Distance from Interior of Building to the Outdoors D-20
Table D3.A.6: Minimum Requirements for Number of Exits for Building Groups and Building Functions D-21
Table D3.D.3: Minimum Height of Fall Protection Barriers D-25
Table D3.D.4: Size and Location Requirements for Openings in Fall Protection Barriers D-25
Figure D3.E.2: Going and Riser Size and Configuration D-27
Table D3.E.4 Going and Riser Size and Configuration D-28
Figure D3.G.6: Ramp Configuration and Handrails D-30
Section E Hazardous Substances
Table E1: Section E- Overview of Applicable Sections in the NBC E-2
Table E1.B.2: Priority for Action to Mitigate Harmful Impacts from Hazardous Substances E-5
Section F Interior
Table F1: Section F - Overview of Applicable Sections in the NBC F-2
Table F3.A.3: Wet Area Protection F-10
Table F3.C.6: Sanitary Compartments Required per Building Function F-12
Table F5.A.1: Minimal Finishes for Exposed Steel F-18
Table F5.B.4: Recognised Eco-Labels for Interior Finishes F-19
Section G Servicing
Table G1: Section G - Overview of Applicable Sections in the NBC G-2
Figure G1.B.1: Piping Penetrations in Steel Framing G-4
Figure G1.B.5: Attachments for Steel Noggin G-5
Table H2.A.1: Recommended Minimum Septic Tank Sizes for Residential Properties G-9
Figure G2.B.5: Minimum SETBACKs for On-Site Wastewater Management Systems G-11
Table G3.E.3: Scalding Time from Hot Water G-19
Table G4.A.1: Requirements for Electrical Installers G-23
Figure G4.B.2: Examples of Electrical System Components G-24
Figure G4.D.5: 3-Pin Plug and Outlet/Socket G-27
Figure G4.G.1: Colour Coding for Wiring G-30
Table G4.L.3: Underground Wiring Enclosures for Cable Types G-36
Figure G4.M.6: Earthing System Components G-38
Figure G4.N.2: Examples of Equipotential Bonding G-40
Table G4.O.1: Electrical Installation Protection in Wet Areas G-42
Table G4.O.2: Electrical Equipment Protection for Swimming Pools G-44
Figure G4.P.4: Lightning Protection System Examples G-45
Table G4.R.7: Minimum Safety Clearances for Aerial Conductors G-48
Table G4.Q.8: Maximum Size and Span for Aerial Conductors G-49
Table G4.R.12: Minimum Spacing Between Aerial Conductors at Supports G-50
Section H Climate Change Adaptation
Table H1: Section H - Overview of Applicable Sections H-2
Figure H1.A.1: Coastal Flood Level and Design Flood Level H-4
Figure H1.B.1: Finished Floor Level Sited Above Coastal Flood Level H-5
Table H1.B.3: Permitted Foundation Types in Coastal Zones H-6
Figure H1.B.8: Properties on Edge of Coastal Zone H-7
Figure H1.D.1: Water-Resistant Floor and Wall Materials in the Flood Risk Zone H-8
Table H2.A.1: Best Practices for Weathertight Construction for Buildings Less than 3 Storeys H-10
Figure H2.E.4: Example of Waterproof Membrane and Flashing for Door Stoop H-13
Figure H3.3: Example of Energy Efficient Design Techniques H-16
Table H.3.A.1: Required Evidence for Thermal Performance per Building Group H-17
Figure H3.C.3: Thermal Chimney in Exterior Wall H-21
Table H3.G.9: Energy Star Suggested Fan Sizes per Room Size H-23
Figure H6.A.1: Supplementary Roof H-39
Figure H6.B.2: Example of Waterproof Membrane and Flashing for a Window H-40
Table H7.1: Minimum Green Building Targets for Sustainable Building Materials H-43
Figure H7.1: Minimum Green Roof Components H-46
Figure H7.5: Examples of Extensive and Intensive Green Roofs H-47
Figure H7.A.8(b): Roof Edge Treatment on an Insulated Flat Green Roof and a Sloping Green Roof H-49
Figure H7.A.8(a): Roof Drain on a Flat Green Roof H-49
Figure H7.B.2: Green Roof Vegetation H-51
Figure H7.B.8: Growing Substrate Characteristics H-52
Section J Natural Disaster Resilience
Table J1: Section J - Overview of Applicable Sections in the NBC J-2
Table J1.3: Disaster Resilience Benchmarks for Building Groups J-5
Table J1.B.3: LHL (Low-High-Low) Pressure Sequence During a Cyclone J-6
Table J1.B.1: Cyclones and tropical Storms - Structure, Material and Construction Provisions J-7
Figure J1.B.4: Cyclone Resistant Foundations J-8
Figure J1.B.5: Cyclone Ties for Framing - Roof to Foundation J-8
Figure J1.B.6: Roof Types J-9
Table J1.C.1: Tsunamis - Structure, Material and Construction Provisions J-11
Table J1.D.1: Earthquakes - Structure, Material and Construction Provisions J-13
Table J1.E.1: Landslips - Structure, Material and Construction Provisions J-15
Table J1.F.4: Fire Retardant Treatment for Single Family Residential in Bushfire Areas J-16
Table J1.F.1: Bushfire - Structure, Material and Construction Provisions J-17
Section K Minor Structures / Major Infrastructure
Table K1: Section K - Overview of Applicable Sections in the NBC K-2
Figure K1.B.4: NZCMA Minimum Standards for Concrete Retaining Walls K-6
Figure K2.B.1: Marine Structures K-11
Figure K2.C.3: Seawall Types K-13
Appendix D
Table H.3.A.1 Required Evidence for Thermal Performance per Building Group Ap-D-1
Table AP-D-1 Required Evidence for Thermal Performance Ap-D-1
Table AP-D-2 R-Values for Various Building Materials Ap-D-3
Table AP-D-3 Required Evidence for Thermal Performance per Building Group Ap-D-4
Introduction
About the NBC
The National Building Code of Samoa (NBC) is a Finally, a list of acceptable solutions by approved agencies
performance based set of standards that provides such as from the Standards Association of Australia and
objectives and descriptions of how a building and site New Zealand, are provided that, if followed, will satisfy the
should be constructed to achieve a structurally-sound PERFORMANCE REQUIREMENTS.
and sustainable built environment. As a performance
based document, the NBC describes the outcome of a It must be recognised that a building code cannot cover every
DEVELOPMENT project rather than prescribing a step- issue concerned with the design and construction of buildings.
by-step method of how to construct. In the case of innovative, complex or unusually HAZARDOUS
building proposals, or other building work beyond the scope
The basic objective of the NBC is to ensure that of the NBC , legislation may provide for other suitable action.
acceptable standards of structural sufficiency, fire safety,
health, amenity and response to the impacts of climate
change are provided so that buildings, facilities and sites Layout of the NBC
are constructed, maintained and demolished in a safe The NBC begins with Section A - General Provisions that
and environmentally responsible manner. apply in all situations including definitions and building
classifications. It is then divided into nine sections:
The provisions in the NBC are intended to extend
no further than is necessary to safeguard the health Section B - Stability
and safety of people and the environment. They are Section C - Fire Protection
intended to be cost effective, not needlessly onerous in Section D - Access
their application, to promote design innovation, and be Section E - Hazardous Substances
easily understood. Section F - Interior
Section G - Site Servicing and Waste
Section H - Climate Change Adaptation
Update from the 1992 Building Code Section J - Natural Disaster Resilience
The NBC is an update from the previous Building Code Section K - Accessory Structures
that was enacted by the Government of Samoa in 1992
and replaces it in its entirety. The basic structure of the Enabling Legislation
1992 Building Code was used for the NBC, but many new The NBC is brought into effect by The Ministry of Works Act
sections are added to respond to current environmental 2002 (as amended), which empowers the Ministry of Works,
issues facing Samoa today. Where still valid, wording Transportation and Infrastructure to regulate certain aspects of
from the 1992 Building Code has been retained, but the building process including the creation and administration
much of it is updated to respond to current construction of the National Building Code, which has now been renamed
standards. as the National Building Code.
What is in the NBC? The legislation also outlines procedures, among other things,
The NBC provides a list of standards to be used for the for amendments to the NBC, compliance, offences and liability,
construction, maintenance and demolition of buildings, inspections, suspension or revocation of a BUILDING PERMIT,
site servicing and amenities on site. and requirements to comply.
When reading the NBC, all blue-coloured words
represent different BUILDING FUNCTIONS as defined in Authority of the NBC
Section A1, while all capitalised words are included in the According to the Ministry of Works Act, 2002, as amended,
definitions in Section A3. provisions in the NBC apply to all proposed DEVELOPMENT
projects that are under consideration for a BUILDING PERMIT
Section A is different from the rest in that it provides from the date that the NBC is enacted. Requirements in the
definitions and other classifications that apply to all NBC will extend throughout the LIFESPAN of the project, for
other sections in the document. SPECIFIED SYSTEMS, maintenance, alteration and demolition.
Sections B through K list provisions that must be The NBC may be used as a guideline or reference document by
satisfied in order for a BUILDING PERMIT to be granted other government ministries and agencies for Government of
and/or for a DEVELOPMENT project to be endorsed Samoa approvals such as a Development Consent application
by the Government of Samoa. Each Section has a list (required by PUMA), but the provisions in the NBC are only
of objectives followed by a list of PERFORMANCE enforceable for the BUILDING PERMIT approval process,
REQUIREMENTS describing the outcome that must be maintenance, alterations and demolition via the Ministry of
achieved. A list of DEEMED-TO-SATISFY PROVISIONS Works Act, 2002, as amended. The ability of a proposed
are associated with all PERFORMANCE REQUIREMENTS DEVELOPMENT to meet the requirements in the NBC does
that describe methods, outcomes, materials and not override any decision on Development Consent or
measurements that if followed will be deemed to satisfy other approvals of the Government of Samoa.
some or all of the PERFORMANCE REQUIREMENTS.
i
Building Regulations The Acceptable Solutions contain standards approved by
The Ministry of Works Act 2002 (as amended) provides for REGISTERED TESTING AUTHORITIES, Approval Boards and
the creation and administration of BUILDING REGULATIONS Regulatory Agencies acceptable to Government of Samoa.
which are administered by the Ministry of Works,
Transportation and Infrastructure (MWTI). All references to an Acceptable Solution, Standard, plan
or document refers to the latest edition or issue, together
They set out procedures for the BUILDING PERMIT approval with any amendment and only so much as is relevant in the
process, including: context in which the document is quoted.
• submission and approval procedures In some cases, Acceptable Solutions, standards and
references developed in other countries have provisions that
• issue of BUILDING PERMITS are more appropriate for the foreign context. To ensure that
Acceptable Solutions, rules, specifications and provisions
• inspections during and after construction from other countries are not in conflict with the standards
in Samoa, the following exclusions apply to documents /
• provision of evidentiary certificates standards written in foreign countries:
• issue of certificates of occupancy or compliance (a) the respective rights, responsibilities or obligations
between the foreign body and any manufacturer, supplier
• a ccreditation or approval of materials or components or purchaser are not applicable
• review and enforcement of standards (b) the responsibilities of any tradesman or other building
operative, architect, engineer, authority, or other person
• fees and charges or body to the foreign country will not be required
The Submission Requirements listed at the end of each (c) required submission for approval of any material building
subsection in Sections B to K provide a general description component, form or method of construction, to any
of the information required to satisfy that particular section person, authority or other body will not be enforced
of the NBC, and should not be thought of as a complete list unless specifically requested in the NBC
of requirements.
(d) submittal of a material, building component, form or
method of construction for review by the Standards
Mandatory Provisions in the NBC Association of Australia, Standards Association of
The following provisions of the NBC are mandatory: New Zealand or other body in a foreign country is not
applicable
(a) Section A: General Provisions
(e) permitting a departure from the Acceptable Solution
(b) O bjectives listed at the beginning of each section rule, specification or provision at the sole discretion of
the manufacturer or purchaser, or by arrangement or
(c) PERFORMANCE REQUIREMENTS listed at the agreement between the manufacturer and purchaser is
beginning of each subsection in Sections B to K not permitted, unless approved by the Government of
Samoa as part of the BUILDING PERMIT approval process
Deemed to Satisfy Provisions Objectives, Performance Standards and Deemed-To-Satisfy
Provisions in the NBC take precedence regarding any
For every section in the NBC, a list of Deemed to Satisfy
difference between it and any Acceptable Solution, rule,
Provisions follows the PERFORMANCE REQUIREMENTS.
specification or provision listed in this document.
The DEEMED-TO-SATISFY PROVISIONS list techniques and
standards that, if followed, will satisfy one, some or all of the
Further, references in the NBC to any Standard or Code of
PERFORMANCE REQUIREMENTS for the subsection. The
Practice issued by the Standards Association of Australia or
applicant must list the DEEMED-TO-SATISFY PROVISIONS
New Zealand, or such other body, exclude the need for:
that apply, and demonstrate how they are fulfilled to
demonstrate compliance with the PERFORMANCE
(a) compliance with NZS 1900 wherever it is quoted in
REQUIREMENTS.
any standard
(b) compliance with any laws and legislation that are not
Acceptable Solutions, Standards and other
Samoan
References
For every subsection, the Deemed to Satisfy Provisions
are followed by a list of Acceptable Solutions that, if
Alternations to Non-Conforming Existing Buildings
followed, are sufficient to satisfy the PERFORMANCE
Buildings, Facilities, Siteworks, Site Servicing and Sites that
REQUIREMENTS of the NBC. The ACCEPTABLE SOLUTIONS
exist prior to the enactment of the NBC that do not comply
and/or the DEEMED-TO-SATISFY PROVISIONS may be
with the provisions in the NBC are not required to comply
used by the applicant to demonstrate compliance with the
with the NBC. However, if an application is made to alter,
PERFORMANCE REQUIREMENTS and the Objectives.
renovate, add-on, change or demolish the structure or site
ii