The guide for Canterbury builders - Above-floor work

THE GUIDE FOR
CANTERBURY BUILDERS
ABOVE-FLOOR
WORK
[ Your new best friend]
About this booklet
loor Work,
This booklet, Above-Floor Work, and its companion booklet Below-F
for repairing
are for builders and others wanting an overview of requirements
the
and rebuilding houses in the Canterbury Green Zone. They outline
for working in
regulatory requirements for builders, and highlight special issues
the Canterbury Green Zone.
These booklets are an introduction to the more detailed guidance
published by
g and
the Ministry of Business, Innovation and Employment (MBIE): Repairin
Guidance).
rebuilding houses affected by the Canterbury earthquakes (MBIE
Links are provided to the MBIE Guidance, which should be referred
to for more
detailed information.
ABOVE–FLOOR
Work:
REPAIRING TIMBER
STRUCTURES
If you’re building in Canterbury...this is important!
Repairing a post-earthquake building is different from carrying out day-today repairs. Floor structures may have been twisted, wrenched, cracked or
tilted so much that their repair, relevelling or replacement must be
considered before any other repairs are done.
In most cases, decisions regarding any earthquake repairs on houses
in Canterbury will be made by a Project Management Office (PMO),
designer, or engineer.
They will engage builders on behalf of the building’s insurers or
owners to undertake those repairs – under usual building contract
terms and conditions.
BUILD IT RIGHT The groundwork
CANTERBURY
for good decisions.
Disclaimer: This document is a guide only. It should not be used as a substitute for legislation or legal advice. The Ministry of
Business, Innovation and Employment is not responsible for the results of any actions taken on the basis of information in
this document, or for any errors or omissions.
© Crown Copyright 2013
This booklet, Above-Floor Work, is an introduction
to MBIE’s guidance for repairs to the framework
above floor, including chimneys and retaining
walls, and gives links to more detailed information.
MBIE published the guidance Repairing and
rebuilding houses affected by the Canterbury
earthquakes to support a quality rebuild in
Canterbury. It is available at www.dbh.govt.nz/
guidance-on-repairs-after-earthquake
A BOV E-FLOOR WORK – A PRIL 2013
The MBIE
Guidance
can be
viewed o
nline
1
What this booklet covers
This booklet sets the scene for building in Canterbury’s Green Zone and
gives an overview of the ‘nuts and bolts’ of above-floor work.
It covers the repair and replacement of structural framing, bracing,
chimneys and fireplaces, and retaining walls for buildings in the Canterbury
Green Zone.
Refer to MBIE Guidance Introduction, and Part C, section 11 –
Introduction to TC3.
While it is mainly concerned with one or two storey timber-framed
dwellings (i.e. houses built to NZS 3604:2011 Timber framed buildings), it
also comments on other building types, covers garages and outbuildings,
and gives tips for installing new services.
Alert: The companion guide, BELOW-FLOOR WORK, COVERS
repairs to foundations. It is important that foundations
and ground floors are repaired or replaced, BEFORE
starting any above-floor repair or rebuilding.
Alert: Repairing or rebuilding earthquake-damaged
CONTENTS
SETTING THE SCENE
Building in the Canterbury Green Zone
5
NZ Regulations
9
THE NUTS AND BOLTS
Above-floor work
14
Structural frame connections and bracing
16
Wall framing
16
Roof framing
17
Bracing17
Repairs to plaster-board or plywood braced panels
19
Other construction types
21
Chimneys and fireplaces
22
Retaining walls
27
Preventing falls
30
Other useful information
32
houses may involve specific engineering design. There
is more information IN THIS BOOKLET under Specific
Engineering Design - when it is required, and THERE IS
more detail PROVIDED in the MBIE guidance.
2
A BOV E-FLOOR WORK – A PRIL 2013
3
SETTING
THE SCENE.
Building in
the Canterbury
Green Zone
Lessons learned from building performance in the Canterbury
earthquakes have led to some improvements in the way houses are
designed and constructed.
Generally, house framing and bracing performed well; especially for
housing sites on the flat. In most cases there was only minor structural
damage, along with damage to finishes, services, and site works.
However, the performance of some house foundations on flat sites was less
successful, mainly due to liquefaction, stretching over the building footprints
(lateral spreading), and tilting of floors (differential ground settlement). So,
more attention is being paid to ground conditions and foundation design.
The Technical Categories – or “TCs”
The main changes that affect repairing and rebuilding houses damaged in
the Canterbury earthquakes relate to the land’s Technical Category.
Flat areas of the Canterbury Green Zone are divided into three Technical
Categories, or TCs.
NOTE: These categories provide a guide to the level of
site investigation required and the appropriate foundations
for the house.
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Each property is listed in one of the following:
Specific Engineering Design – when it is required
• TC1 is where land damage from liquefaction is unlikely in future large
earthquakes. Standard residential foundation assessment and
construction is appropriate.
Specific engineering design is when the design or design method is
non-standard (i.e. outside the Acceptable Solution or Verification Method).
• TC2 is where liquefaction damage is possible in future large earthquakes.
Shallow ground investigations may be required when repairing or
replacing foundations. There are foundation repair and rebuild options in
the MBIE Guidance.
Specific engineering design will usually be done by a Chartered Professional
Engineer (CPEng).
• TC3 is where liquefaction damage is possible in future large earthquakes.
Geotechnical engineering assessment may be required to select the
appropriate foundation repair or rebuild.
For more about the TCs, see MBIE Guidance section 1.4.3 –
Technical scope, and Part C, section 12 – Future land performance
in TC3.
Confirming the TC is an important starting point before doing repairs,
especially for foundations. The TC will indicate which recommendations in
the MBIE Guidance are best suited for the site.
Helpful tip: Find out the Technical Category and other
land information for residential sites at the CERA website
www.landcheck.org.nz
See page 9 The Building Code and Building Consents.
NOTE: If a building needs extensive repairs – especially if
repairs are to its structure, roof, wall cladding, windows
or doors – a professional engineer, architect or designer
will generally be involved.
Alert: Repairing or rebuilding a timber-framed house
generally needs specific engineering design if:
• The building is more than two storeys high (i.e. more
than 10 metres above ground)
• The building work involves foundations for sites in
the TC3 zone.
It is important to repair or replace foundations and ground floors
before doing any above-floor repair or rebuilding. Check out the
companion guide to repairs Below-Floor Work.
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Some useful links:
• Concrete or concrete block construction: refer to NZS 4229 Concrete
masonry buildings not requiring specific engineering design, and to the
Cement and Concrete Association of New Zealand’s Code of Practice
CCANZ CP 01:2011, available at www.ccanz.org.nz
• Steel stud construction: refer to the National Association of Steelframed Housing Handbook – Best practice for design and construction of
residential and low-rise steel framing, available at www.nash.asn.au
NZ REGULATIONS
The Building Code and Building Consents
The Building Act 2004 (Building Act) contains provisions that are designed
to ensure buildings are safe and healthy to live in.
The Building Code (established under the Building Act) sets the performance
standards that all building work must meet.
The Building Code is divided into clauses (sections) covering each aspect of
a building, such as structure, fire and weathertightness.
Each clause of the Building Code has at least one Acceptable Solution or
Verification Method (see www.dbh.govt.nz/compliance-documents).
These are ‘ready-made’ design solutions that you can use to comply with
the Building Code. However, these solutions are not mandatory and
following them is only one way of complying with the Building Code.
ALL building work MUST comply with the Building Code, whether or
not it requires a building consent.
For more information on the regulatory context for Canterbury
earthquake repairs, refer MBIE Guidance Part B, section 8.2 –
Regulatory requirements.
Work that MUST HAVE a Building Consent
All new building work will need a building consent, except the minor work
covered by Schedule 1 of the Building Act (see next page).
Work that must have a Building Consent includes:
• Repairs or replacement of structural components (however, some minor
structural repairs may not need a building consent – check with the local
building consent authority)
• Repairs or replacement of fire safety parts of a building
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• Replacing materials that have failed to meet the durability requirements
of the Building Code, such as a leaking roof or wall cladding that is less
than 15 years old.
NOTE: repairs or maintenance of materials such as
claddings that have failed due to earthquake damage, do
not require a building consent.
Work that DOES NOT require a Building Consent
Some minor building work does not require a building consent – this is
known as ‘exempt building work’. A list of exempt work is contained in
Schedule 1 of the Building Act (for more details see below).
For building repairs, exempt work generally includes:
• Repair or replacement of building components or building services using
materials that are the same, or comparable, to existing materials
• Construction, repair or replacement of walls with less than 1.5 metres of
retained ground, that are (1) back-filled no higher than the wall, and
(2) do not support loads other than the backfilling. See Retaining Walls
Alert: For a complete list of work that does not
require a building consent refer TO:
•www.legislation.govt.nz (BUILDING ACT SCHEDULE 1)
•www.dbh.govt.nz/bc-no-consent
•www.ccc.govt.nz/homeliving/buildingplanning/
buildingconsents/exemption.aspx
Remember that, even when a building consent is not
required, all building work must still comply with the
Building Act and the Building Code.
What you are legally responsible for
If you are carrying out residential building repairs or new building work under
a building contract, you are legally responsible for ensuring that the work:
• Is properly carried out and completed
• Complies with the agreed contract terms
• Is suitable for its intended purpose.
Alert: These are known as implied warranties for the
• Construction, repairs or replacement of a deck which is less than
1.5 metres from the ground at any point
quality of your work. You cannot contract out of
• Installation, replacement, or removal of a door or window
these (see sections 397 and 399 of the Building Act).
• Non-structural internal alterations and repairs (repairs to internal wall
lining used for bracing do not need a building consent)
• Any other building work which the territorial authority (local council)
considers to be exempt (these can be general or case-by-case
exemptions under Schedule 1(k) of the Building Act).
If you are designing or giving advice on building work, you are also legally
responsible for that advice. Builders who both design and carry out repairs
to buildings are therefore legally responsible for the work complying with
the Building Code.
NOTE: It is important for builders to be aware of their
legal responsibilities, especially if doing repairs without
a Building Consent. Refer to Work that DOES NOT require a
Building Consent.
GETTING A BUILDING CONSENT IS ONE WAY OF MAKING SURE THE
WORK COMPLIES WITH THE BUILDING CODE.
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Restricted Building Work is building work that MUST be carried out by a
Licensed Building Practitioner (LBP). It only applies to houses or apartment
buildings up to 10 metres in height and excludes mixed–use apartments.
If you are an LBP
You can do Restricted Building Work you are licensed for, relating to:
• The dwelling’s structure, such as work on foundations, framing and
bracing
• Its weathertightness, such as building work relating to windows, doors,
roofing, cladding
• Some fire safety design work.
Helpful tip: Go to www.dbh.govt.nz/builditright for more about
Restricted Building Work and Licensed Building Practitioners.
LBPs, once they have completed their part of the Restricted Building Work,
must provide a “Record of work” form, confirming which parts of the
Restricted Building Work they carried out or supervised. LBPs must give
this form to homeowners and the territorial authority (local council).
If you’re NOT an LBP
If you are not an LBP, you can carry out Restricted Building Work UNDER
THE SUPERVISION OF AN LBP licensed for the work.
You can also carry out:
• Work not considered Restricted Building Work
• Work that does not require a building consent
• Any work on buildings that are not used for living in, such as sheds,
stand-alone garages and carports.
12
The nuts
AND bolts.
AN INTRODUCTION TO GUIDANCE FOR REPAIRING AND REBUILDING HOUSES
Restricted Building Work and Licensed Building
Practitioners
ABOVE-floor WORK
If the house is not timber framed, these may be useful:
Buildings covered in the MBIE Guidance
• Steel stud construction – the NASH Handbook – Best practice for
design and construction of residential and low-rise steel framing, see
www.nash.asn.au.
This booklet, and the MBIE Guidance, is for repairing residential properties in
Canterbury’s Green Zone that are one or two storey, timber framed, dwellings
(i.e. houses built to NZS 3604).
• Concrete or concrete blocks – NZS 4229, and the Cement and Concrete
Association – Code of Practice for Weathertightness Design.
There are also some useful tips for repairing other building types (i.e. masonry
houses built to NZS 4229).
NOTE: most often, decisions for the repairs will be made by a
Project Management Office (PMO), designers, or engineers.
They will engage builders, under usual building contract
terms and conditions, to undertake the work on behalf of
insurers or owners.
Where extensive repairs are required, especially repairs to the structure, roof,
wall cladding, windows or doors, it is recommended that a professional
engineer, architect or designer is consulted.
Alert: Repairing or rebuilding THE ABOVE-FLOOR SECTION
OF a timber-framed house generally needs specific
engineering design if:
• The building is more than two storeys high OR more
than 10 metres above ground
• The building work involves foundations for sites in the
TC3 zone.
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STRUCTURAL FRAME
CONNECTIONS AND BRACING
Wall framing
Where wall frame damage has occurred because of the earthquakes, it is
possible that frame joints have pulled apart, structural fixings have become
loose, or that whole walls have become dislodged or moved out of plumb.
Because bottom plates may have lifted and resettled, floor coverings and
lower wall linings may need to be removed to allow proper inspection if
damage is suspected to ‘hold-down’ fixings.
Typical framing damage (and associated repairs) will include:
Roof framing
If house foundations and wall frames are damaged, it’s also possible that the
roof framing has been affected. Gable-end roofs may have been damaged
more than hip roofs, which are self-bracing.
Most likely roof framing damage (and associated repairs) will include:
• Broken roof framing – replace broken framing and fixings
• Broken bracing strap connections – replace broken straps and re-tighten
existing strapping with tensioning inserts.
If it’s difficult to access roof spaces, especially where top plate fixings need to
be inspected, it may be necessary to remove parts of the ceiling or soffit
linings to check the roof properly.
• Broken framing – replace broken framing and fixings
Bracing
• Framing joints that have separated – pull back into line and refix
Most timber-framed houses built before 1978 (the first publication of
NZS 3604) had their wall bracing provided by either flush timber braces or
solid timber braces.
• Bottom plates either separated from floors or with broken fixings – refix
bottom plates to floors and replace ‘shot’ fixings to concrete slabs with
bolt anchors
• Damaged brace connections (e.g. nail straps)– replace structural
connectors (these are especially important to the overall stiffness and
strength of the house).
Refer to MBIE Guidance Table 7.1 for recommended bracing repairs.
Houses built after 1978 generally used sheet bracing, sometimes in
combination with steel angle or strap bracing. This is usually paper-faced
plaster-board, fibre cement sheet, or plywood. Fibrous plaster sheets were
also commonly used for bracing in the 1980s and 1990s.
Houses generally have braced walls evenly placed across their width and length.
Not all walls in these homes are braced walls. However, it is safer to treat
all lining repairs as if they are bracing elements.
Refer to Below-Floor Work, when considering re-cladding options.
Refer also to MBIE Guidance section 7.9 and Table 7.2 for more on
cladding weights.
16
Ways to repair or replace paper-faced plaster-board and plywood braced panels
are set out in the Table – Repairs to plaster-board lined walls on page 19.
A BOV E-FLOOR WORK – A PRIL 2013
17
For information on the following structural systems, see the MBIE
Guidance section 7:
Repairs to plaster-board lined walls
• Fibrous plaster walls
For a more complete list of possible damage and recommended
repairs, refer to section 7.2 and Table 7.1 of the MBIE Guidance
• Buildings with concrete or concrete block walls
Refer also to BRANZ Bulletin 548 – www.branz.co.nz
• Older buildings with solid timber cut-between or cut-in bracing.
Bracing repairs to buildings with steel portal frame bracing or other proprietary
bracing systems will require specific engineering design.
Lathe and plaster interior wall linings don’t provide bracing, but are often the
first line of resistance during an earthquake and therefore are usually damaged.
See MBIE Guidance Part A, section 7.2 for common damage
and repairs.
Helpful tip: For further information on bracing and fixings, refer to
manufacturer and supplier information and websites.
Damage
Repairs
Minor damage
Re-stop cracking in plaster panels
Lining joint cracks less
than 0.5mm wide
Refix along stud lines where sheets sound or
feel ‘drummy’ or where existing fixings have
popped
No signs of wall movement
Moderate damage
Lining joint cracks more
than 0.5mm wide
Minor perimeter
movement at sheet edges
and skirting
Refix sheets adjacent to existing fixings (may
involve removal of skirtings and cornices)
Where sheet edges are too damaged –
replace sheets and fix as for bracing elements
Significant damage
Refix sheets if:
Lining separation from wall
• diagonal cracks at opening corners are less
than 50mm long and
Wall out of plumb by more
than 10mm over its height
Bottom plates out of
position
• there is only moderate damage (see above).
Otherwise, repair wall framing and fixings and
replace sheets as for bracing elements
Consult sheet manufacturer’s data for bracing sheet fixing information and the
bracing capacities (bracing units/metre) of each product type.
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Helpful tip: Fibrous plaster walls, if damaged, will show irregular
cracking along fixing lines rather than the ‘straight line’ cracking typical
of paper-faced plaster linings.
When repairing masonry veneer walls, check for bracing panels (e.g.
behind underlays) and refix as required.
OTHER CONSTRUCTION TYPES
Masonry walls
Repairs to damaged concrete block and brick masonry walls will depend on
whether / how the walls are reinforced and the amount of grouting used
(some block walls may be only partially filled and double skin brick masonry
is usually unfilled).
Specific engineering advice is required for assessing damage to unreinforced
brick or block masonry walls. Minor cracking in reinforced (two-way reinforced)
concrete block walls, that are well attached to the surrounding structure, can
usually be repaired by grout or epoxy injection and repointing without specific
engineering design.
More extensive cracking in reinforced and unreinforced walls usually means
repairs are not practical and replacement is probably the only option.
Refer to the MBIE Guidance for more about:
• Unreinforced brick masonry walls (Part A section 7.7)
• Concrete block masonry walls (section 7.8).
Light gauge steel framing
For light gauge steel wall and roof framing, damaged lining sheets should be
removed and bent structural members replaced. Re-fix torn or detached rivet/
screw connections, or replace framing assemblies.
Refer MBIE Guidance Part A, section 7.5
Pole frame structures
Pole frame houses generally rely on cross-bracing to stiffen pole structures.
Refer MBIE Guidance Part A, section 7.6 for more on where to check
for damage.
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Chimneys and Fireplaces
Following the Canterbury earthquakes, masonry chimney flues and fire boxes
should be inspected by a bricklayer or engineer and any repairs carried out
BEFORE they are reused.
Alert: MASONRY CHIMNEYS ARE OFTEN THE FIRST THINGS TO BE
Clean Air Requirements
Alert: ENVIRONMENT CANTERBURY HAS RULES ABOUT THE
TYPE AND USE OF FIRES FOR HOME HEATING. THESE COVER
CHRISTCHURCH, KAIAPOI, RANGIORA, AND ASHBURTON. SEARCH
“CHRISTCHURCH HOME HEATING RULES” AND GO TO THE ECAN
WEBSITE WWW.ECAN.GOVT.NZ FOR MAPS AND ADVICE.
DAMAGED IN AN EARTHQUAKE.
The requirements for repairing chimneys and fireplaces apply to:
• Open fires
Alert: IF REPAIRS OR REPLACEMENTS ARE REQUIRED TO FIRE
BOXES, ESPECIALLY FOR OLDER FIREPLACES, THE ENERGY
EFFICIENCY AND CONSERVATION AUTHORITY (EECA) RECOMMENDS
• Enclosed solid fuel burners
ENERGY EFFICIENT WOOD, PELLET OR GAS BURNERS ARE
• Flued gas fires.
INSTALLED, OR HEAT PUMPS CONSIDERED. See www.eeca.govt.nz
Most fireplaces have:
• Chimneys constructed of masonry, metal or a combination of both
• Fire boxes, made of either masonry or steel, and are either (1) enclosed
(with timber framing or masonry surrounds) or (2) free-standing (generally
steel fire boxes only).
Refer MBIE Guidance Part A, section 7.1, and Appendix A3.
NOTE: MBIE GUIDANCE APPENDIX A3 EXPLAINS HOW TO RECOGNISE
CHIMNEY CONSTRUCTION TYPES BY THE NATURE OF ANY DAMAGE,
ESPECIALLY CRACKING, SEEN ON THE OUTSIDE.
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Inspecting flues for damage
Parts of the wall linings around flues and fireboxes may need to be removed
for proper inspection – especially if flues and fireboxes are constructed from
masonry and appear unstable.
If the flue or firebox is out of alignment or ‘tilting’ from vertical, it is a sign of
significant damage and should be replaced.
MBIE Guidance Appendix A3, Figures A3.3, A3.4, and A3.5 give suggested
options for either:
• Repairing brick chimneys, or
• Inserting lightweight stainless steel flues within brick chimneys (for use with
solid fuel burners).
Figure 2 shows the suggested replacement of an internal masonry chimney
with a steel flue and framing assembly. This can be used where the
appearance of a ‘chimney stack’ above the roof is preferred.
FI G U R E : 2
ST E E L F L U E D E TA I L
S U G G E ST E D M A S O N R Y
C H I M N EY R E PLA C E M E NT
W I TH ST E E L F L U E A N D
TI M B E R F R A M I N G
COWL
600mm
MINIMUM
TOP FLASHING
F IGU R E : 1
CE ME NT-BASED
HEAT SHIE LD
C L EA R ANCE S F O R MA S ON R Y F I R EP L ACE S
GUTTE R AND ROOF
FLASHINGS
CLADDING ON
TIMBE R FRAMING
25mm MIN.
ROOF FLASHING
MINIMUM
25mm CLEARANCE
FLUE
INNE R CASING
OUTE R CASING
MASONRY FIRE PLACE
MINIMUM
25mm CLEARANCE
MINIMUM 25mm CLEARANCE ALL
ROUND FOR CONCRETE CHIMNEY
AND FIREPLACE
WALL FRAMING
24
CEILING PLATE
A BOV E-FLOOR WORK – A PRIL 2013
AIR GAP
25
RETAINING WALLS
Chimney and fireplace repairs
Damage
Repair
Damage to:
• Roof flashings around the flue
•Cowls
• External ‘anti-sway’ ties
Replace damaged units and fixings,
including any associated damage to
flues or surrounding roofing.
Dislodged chimney pots
Replace with lightweight metal
cowls.
Blocked clearways between flue
and surrounding timber or other
combustible material
Important: Maintain a minimum of
25 mm clear space between a
masonry flue or fire box and
combustible materials such as
timber framing (See Figure 1).
For clear spaces around metal flues
or fireboxes, consult manufacturer’s
installation recommendations or see
Acceptable Solution C/AS1.
Broken or missing structural ties
supporting masonry flues or outer
casing to frames
Replace broken ties and tie fixings.
For masonry flue repair options, see
Figure 1 Clearances for masonry
fireplaces, Figure 2 Steel flue detail,
and MBIE Guidance Figure
A3.3-A3.5.
Cracked plaster around masonry
flues or missing mortar from flue
joints
If the inspection report indicates
damage, consider replacement
of masonry flue with a stainless
steel flue.
Dislodged masonry units.
Cracking to flue, especially where
flue joins the breastwork
Recommend replacement of
masonry flue with a stainless steel
flue.
26
Retaining walls on hillside properties involve a range of problems and can be
difficult to repair. If a retaining wall has been damaged and the surrounding ground
and landscape appears unstable, it’s important that the site is assessed by a
professional engineer as being safe to work on before any repair work goes ahead.
Specialist engineering advice
In most cases, specialist engineering advice will be required before
undertaking any substantial repairs or replacements to retaining walls. Damage
to retaining walls caused by the earthquakes can be difficult to assess and
may be invisible if below ground or behind the wall.
Obvious signs of damage include:
• Loss of ground support or undermining
• Forward tilting or ‘rotation’
• Broken wall units
• Dislodged wall units.
For a detailed description of possible damage and repair options for
retaining walls, refer MBIE Guidance Part A, section 6.2 and Table 6.1.
Walls less than 1.5 metres high
Walls retaining less than 1.5 metres* of ground may not require a building
consent (refer to Work that does not require a building consent).
* NOTE: In rural areas, this limit is extended to 3 metres
where walls are designed by CPEng qualified engineers.
Alert: Remember that even when a building consent is not
required, all building work must still comply with the
Building Act and the Building Code.
A BOV E-FLOOR WORK – A PRIL 2013
27
Before doing repairs:
• Check the site’s Project Information Memorandum (PIM) for records of
underground services
FI G U R E : 3B
SURCHARG E GROUND
• Make sure there are no indications of ground slip or ground movement in the
area of the wall (see MBIE Guidance, section 6.1)
• Test that there is ‘good ground’ beneath the footing (see MBIE Guidance
section 3.4 for ways to determine ‘good ground’).
Surcharge loadings
O
45 IF ROCK BACK FILLING
Before repairing or rebuilding a retaining wall, get specific engineering advice if
the wall has surcharge loadings (see Figures 3A, 3B, and 3C) such as:
O
SURCHARG E
ANGLE
• Retained ground higher than the wall, or
27 IF CLAY BACK FILLING
O
19 IF SAND BACK FILLING
• Roadways, buildings, other retaining walls, swimming pools or other
structures above the wall.
F IGU R E : 3 A
SURCHARGE FREE ZONE
F IGU R E : 3 C
S U R CHA R GE :
• ROADWAY
• BUILDING
O
• SWIMMING POOL
O
• OTHER RETAINING WALL E.T.C.
45 IF ROCK BACK FILLING
SURCHARGE
ANGLE
27 IF CLAY BACK FILLING
O
19 IF SAND BACK FILLING
O
45 IF ROCK BACK FILLING
O
SURCHARGE
ANGLE
28
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27 IF CLAY BACK FILLING
O
19 IF SAND BACK FILLING
29
A serious fall from
height could cost
you your life.
you can’t put a
price on that.
PLUS if something goes wrong and a worker has an accident:
• You lose productivity
• You risk your reputation, and
• You risk a serious fine.
How to make your site safer
A safe site starts with safe attitudes to work. At the end of the day, everyone
has the right to return home safely from work.
Three ways you can make a difference are:
1 Look out for yourself, your workers, and your mates. If you see unsafe
working conditions, speak up.
Dangerous activities such as walking the top plate are not ‘part of the job’. It
recently cost an apprentice his legs, and changed his life forever.
2 Check out the site before work starts. Think about the tasks you might be
If current construction industry injury rates continue during the Canterbury
rebuild, we estimate one to two people will die each year on Canterbury
work sites.
3 Make sure you and your workers have the right training to complete the job.
If you run a construction business, using height safety
equipment makes good financial sense.
Some businesses report a lift in productivity and a reduction in build time
through the use of height safety equipment.
doing – identify and address any hazards.
Helpful tip:
Visit www.dol.govt.nz/prevent-falls to find out more about:
• Preventing falls from height and keeping your site safe
AND
• Identifying site hazards.
“Walking around scaffolding is quicker for the
guys, rather than having to walk around the
top plate and stepping over trusses every five
seconds to get to the other side.”
STEVE TITMUSS, HAWKINS PROJECT MANAGER
30
A BOV E-FLOOR WORK – A PRIL 2013
31
Other useful information
MBIE’s guidance, Repairing and rebuilding houses affected by the Canterbury
earthquakes, contains detailed information about the topics discussed in this
booklet and also repair and rebuilding work to the house’s foundations. See
www.dbh.govt.nz/guidance-on-repairs-after-earthquake
Other useful information in the MBIE Guidance
includes:
• “Insurance and Regulatory requirements”
– MBIE Guidance section 8
• “Assessment and repair options for chimneys”
– MBIE Guidance Appendix A3
TH E GU IDE
FOR
CA NT ER BU RY
BU ILDER S
BELOW-FLOO
R
WORK
[ Your new
best friend]
• “Basis for confirming compliance with the
Building Code” – MBIE Guidance Appendix C1
The companion to this booklet, Below-Floor Work,
is also based on the MBIE Guidance.
Other relevant publications and links include:
• “Disaster Recovery – Asbestos Management”
– www.dol.govt.nz/quake/asbestos-management.pdf
• “Canterbury Home heating rules”
– www.ecan.govt.nz/advice/your-home/home-heating/pages/Default.aspx
• “Repair approaches” – BRANZ Bulletin 548 – www.branz.co.nz
• “Guidance on garage classification” – www.dbh.govt.nz/codewords-35-1
• “Updates to guidance on foundation repairs in TC3 zone”
– www.dbh.govt.nz/guidance-on-repairs-after-earthquakes
• Building consent exemptions –
www.ccc.govt.nz/homeliving/buildingplanning/buildingconsents/
exemption.aspx
32
Ministry of Business, Innovation and Employment (MBIE) – Hikina Whakatutuki
MBIE develops and delivers policy, services, advice and regulation to support economic
growth and the prosperity and wellbeing of New Zealanders.
MBIE combines the former Ministries of Economic Development and Science +
Innovation, and the Departments of Labour and Building and Housing.
A BOV E-FLOOR WORK – A PRIL 2013
33
Published in April 2013
by Ministry of Business, Innovation and Employment, PO Box 10-729,
Wellington, New Zealand.
This document is issued as guidance under section 175 of the Building Act
2004. While the Ministry has taken care in preparing the document, it should
not be relied upon as establishing compliance with all relevant clauses of
the Building Act or Building Code in all cases that may arise. The document
may be updated from time to time and the latest version is available from
the Ministry’s website at www.dbh.govt.nz.
ISBN [978-0-478-39940-0] (Print)
ISBN 978-0-478-39941-7 (Online)
Download PDF