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PREVENTING FALLS IN HOUSING CONSTRUCTION

DraftCode of Practice

PREVENTING FALLS IN HOUSING CONSTRUCTIONSAFE WORK AUSTRALIA MEMBERS’ MEETING

6SEPTEMBER 2011

DRAFT CODE OF PRACTICE30 SEPTEMBER 2010

Table of ContentsFOREWORD 3SCOPE AND APPLICATION 31. INTRODUCTION 5

1.1 Who has health and safety duties in relation to falls? 51.2 The meaning of key terms 61.3 What is required to manage the risk of falls?6

2. SAFE WORK METHODS FOR THE CONSTRUCTION SEQUENCE 82.1 The hierarchy of risk control 82.2 Uneven land (including, cliffs, banks, holes) 82.3 Excavations or trenches into which a person could fall 92.4 Elevated timber floor or concrete slab from which a person could fall 92.5 Standing/erecting the walls for the ground floors 92.6 Installing floor joists/beams for the first and second floors 92.7 Installing flooring sheets at the first and second floor levels 92.8 Standing/erecting the walls for the first or second floor levels 102.9 Loading the wall frame with trusses/roof framing 112.10 Placing, standing and fixing trusses/rafters to create a roof frame 122.11 Fixing roof battens to trusses / rafters 172.12 Fixing fascias and gutters 192.13 Installing roof membrane 19

3. TEMPORARY ACCESS AND EDGE PROTECTION 213.1 Guardrailing as edge protection 213.2 Catch platforms on scaffolds and hanging brackets 233.3 Bricklayer’s heavy duty trestles 243.4 Hanging brackets incorporating edge protection 243.5 Ladders 25

APPENDIX A – OTHER RELEVANT INFORMATION 27


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DRAFT CODE OF PRACTICE30 SEPTEMBER 2010 PAGE: 2 OF 27

1. FOREWORDThis Code of Practice on how to prevent the risks of falls in housing construction is an approved code of practice under section 274 of the Work Health and Safety Act.

An approved code of practice is a practical guide to achieving the standards of health, safety and welfare required under the Work Health and Safety Act (the WHS Act) and the Work Health and Safety Regulations (the Regulations).

A code of practice applies to anyone who has a duty of care in the circumstances described in the code. In most cases, following an approved code of practice would achieve compliance with the health and safety duties in the WHS Act, in relation to the subject matter of the code. Like regulations, codes of practice deal with particular issues and do not cover all hazards or risks which may arise. The health and safety duties require duty holders to consider all risks associated with work, not only those for which regulations and codes of practice exist.

Codes of practice are admissible in court proceedings under the WHS Act and Regulations. Courts may regard a code of practice as evidence of what is known about a hazard, risk or control and may rely on the code in determining what is reasonably practicable in the circumstances to which the code relates.

Compliance with the WHS Act and Regulations may be achieved by following another method, such as a technical or an industry standard, if it provides an equivalent or higher standard of work health and safety than the code.

An inspector may refer to an approved code of practice when issuing an improvement or prohibition notice.

This Code of Practice has been developed by Safe Work Australia as a model code of practice under the Council of Australian Governments’ Inter-Governmental Agreement for Regulatory and Operational Reform in Occupational Health and Safety for adoption by the Commonwealth, state and territory governments.

A draft of this Code of Practice was released for public consultation on 26 September 2011 and was endorsed by the Select Council on Workplace Relations on [to be completed].

SCOPE AND APPLICATIONThe Code provides practical guidance for persons conducting a business or undertaking who have duties under the WHS Act and the Regulations to eliminate and minimise the risk of falls in housing construction.

This Code will help to identify hazards and eliminate or minimise the risk of falls when working on the construction or extension of:

detached houses attached dwellings, separated from each other by a fire resisting wall, such as terrace, row

or town houses boarding and guest houses, hostels or similar with a floor area <300m², and ancillary buildings to the above, such as private garages, gazeboes and carports.

Note: The above points are based on Classes 1, 2 and 10 of the Building Code of Australia.This Code does not apply to multi-storey buildings (i.e. above two habitable storeys).

This Code should be read in conjunction with the Code of Practice: How to Prevent Falls at Workplaces and the Code of Practice: Managing Risks in Construction Work.


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How to use this CodeIn providing guidance, the word ‘should’ is used in this Code to indicate a recommended course of action, while ‘may’ is used to indicate an optional course of action.

This Code also includes various references to provisions of the WHS Act and regulations to provide context with legal requirements. These references are not exhaustive.

The words ‘must’, ‘requires’ or ‘mandatory’ indicate that these legal requirements exist, which must be complied with.


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2. INTRODUCTION

Falls are a major cause of death and serious injury in Australian workplaces. Fall hazards are found when carrying out common tasks in the construction of a typical one or two storey house (see Figure 1). Falls can also occur at ground level into holes, for example trenches or service pits.

Figure 1: Potential falls in the housing construction industry

1.1 Who has health and safety duties in relation to falls?A person conducting a business or undertaking has the primary duty under the WHS Act to ensure, so far as is reasonably practicable, that workers and other persons are not exposed to health and safety risks arising from the business or undertaking.

A person conducting a business or undertaking has more specific obligations under the WHS Regulations to manage the risk of a fall by a person from one level to another, including requirements to:

ensure, so far as is reasonably practicable, that any work involving the risk of a fall is carried out on the ground or on a solid construction

provide safe means of access to and exit from the workplace, and minimise the risk of falls so far as is reasonably practicable by providing a fall prevention

device, work positioning system or a fall arrest system.

The WHS Regulations classify a number of activities as ‘high risk construction work’ for which a safe work method statement (SWMS) must be prepared before the work starts. High risk construction work includes work that involves a risk of a person falling more than 2 metres. Further


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information on developing a SWMS can be found in the Code of Practice: Managing Risks in Construction Work.

Designers, manufacturers, suppliers, importers and installers of plant or structures that could be used for work must ensure, so far as is reasonably practicable, that the plant or structure is without risks to health and safety. Designers of plant or structures have an important role in eliminating or minimising the risks of falls in the design stage.

Officers, such as company directors, have a duty to exercise due diligence to ensure that the business or undertaking complies with the WHS Act and Regulations. This includes taking reasonable steps to ensure that the business or undertaking has and uses appropriate resources and processes to eliminate or minimise risks of falls from one level to another that are likely to cause injury.

Workers have a duty to take reasonable care for their own health and safety and that they do not adversely affect the health and safety of other persons. Workers must comply with any reasonable instruction given by the person conducting the business or undertaking.

1.2 The meaning of key terms Fall means a fall by a person from one level to another.

Risk of a fall means a circumstance that exposes a worker while at work, or other person while at or in the vicinity of a workplace, to a risk of a fall that is reasonably likely to cause injury to the worker or other person. This includes circumstances in which the worker or other person is:

in or on plant or a structure that is at an elevated level in or on plant that is being used to gain access to an elevated level in the vicinity of an opening through which a person could fall in the vicinity of an edge over which a person could fall on or in the vicinity of a surface through which a person could fall, or on or near the vicinity of a slippery, sloping or unstable surface.

Risk control means taking action to eliminate health and safety risks so far as is reasonably practicable, and if that is not possible, minimising the risks so far as is reasonably practicable. Eliminating a hazard will also eliminate any risks associated with that hazard.

Competent person means a person who has acquired through training, qualification or experience the knowledge and skills to carry out the task.

1.3 What is required to manage the risk of falls?

In order to manage risk under the WHS Regulations, a duty holder must:

a) identify reasonably foreseeable hazards that could give rise to the riskb) eliminate the risk so far as is reasonably practicablec) if it is not reasonably practicable to eliminate the risk – minimise the risk so far as is reasonably practicable by implementing control measures in accordance with the hierarchy of risk controld) maintain the implemented control measure so that it remains effective, ande) review, and if necessary revise all risk control measures so as to maintain, so far as is reasonably practicable, a work environment that is without risks to health and safety.

Managing risk is a systematic process that involves: identifying hazards that may cause injury if necessary, assessing the risks associated with these hazards implementing risk control measures, and reviewing risk control measures to ensure they are effective.


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This Code provides guidance on the type of control measures to prevent persons falling from one level to another on housing construction sites. Specific guidance on the risk management process for falls is available in the Code of Practice: How to Prevent Falls in the Workplace.

Consulting workers Consultation involves sharing of information, giving workers a reasonable opportunity to express views and taking those views into account before making decisions on health and safety matters.

The WHS Act requires that you consult, so far as is reasonably practicable, with workers who carry out work for you who are (or are likely to be) directly affected by a work health and safety matter.

If the workers are represented by a health and safety representative, the consultation must involve that representative.

Consulting, cooperating and coordinating activities with other duty holders

The WHS Act also requires that you consult, cooperate and coordinate activities with all other persons who have a work health or safety duty in relation to the same matter, so far as is reasonably practicable.

There are often multiple contractors involved in building a house, who may each have responsibility for the same health and safety matters because they are involved in the same activities or share the same workplace. In these situations, each duty holder should exchange information to find out who is doing what and work together in a co-operative and co-ordinated way so that all risks are eliminated or minimised as far as reasonably practicable.

For example an electrician working on a roof should consult with other tradespersons who are also working on the site to co-ordinate the provision of suitable fall prevention and co-operate with each other to ensure that each of their activities do not create risks for other workers on the site.

Further guidance is available in the Code of Practice: Work Health and Safety Consultation, Co-operation and Co-ordination.


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3. SAFE WORK METHODS FOR THE CONSTRUCTION SEQUENCE This section identifies safe work methods for common tasks in the construction of a typical house. Commonly these houses are constructed of timber or lightweight metal frames. More specifically, it describes methods that can be used to eliminate or reduce the risk of falls associated with building and cladding a house structure.

2.1 The hierarchy of risk controlIn managing the risks of falls, the WHS Regulations require the following specific control measures to be implemented where it is reasonably practicable to do so:

1. Can the need to work at height be avoided to eliminate the risk of a fall? Carry out any work that involves the risk of a fall on the ground

2. Can the fall be prevented by working on solid construction? A building or structure that is used as an existing place of work and includes safe access

and egress from which there is no risk of a fall from one level to another, for example properly constructed stairs with fixed handrails, flat roofs with a parapet or permanently installed guardrails around the edges.

3. Can the risk of a fall be minimised by providing and maintaining a safe system of work, including: providing a fall prevention device (for example, temporary work platforms, installing guard

rails) if it is reasonably practicable to do so, or providing a work positioning system (for example, an industrial rope access system) if it is

not reasonably practicable to provide a fall prevention device, or providing a fall arrest system so far as is reasonably practicable, if it is not reasonably

practicable to provide a fall prevention device or a work positioning system.

In some cases, a combination of control measures may be necessary, for example, using safety harnesses while working from an elevating work platform.

Control measures are needed where there is a risk of injury irrespective of fall height. For low falls, you should assess the risk and provide reasonably practicable measures that reflect the risk. Work of long duration and higher frequency will usually require control measures higher up the hierarchy to provide adequate protection, for example using a mobile scaffold instead of a ladder.

Further guidance on control measures for falls is available in the Code of Practice: How to Prevent Falls in the Workplace.

You should also ensure that the control measures you select do not create new hazards, for example, electrical risks from contact with overhead power lines or crushing and entanglement from plant, for example elevating work platforms.

2.2 Uneven land (including, cliffs, banks, holes)When first taking possession of a site and prior to beginning construction work, the person with management or control of the workplace (for example, the principal contractor) should conduct a risk assessment of the site. Examples include, where land has been levelled by the developer in preparation to selling the individual allotments, where construction takes place adjacent to an escarpment.

Sometimes where sites have been levelled retaining walls between these parcels/blocks of land can be as high as 4 to 5 metres. Although there is a duty of care on the developer to manage the risk of falling, this duty becomes the principal contractor’s duty of care once the principal contractor takes possession of the land.


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2.3 Excavations or trenches into which a person could fallPrior to beginning erection of a structure as well as during the construction phase, deep excavations may be created into which a person could fall. Control measures to eliminate or minimise the risks of workers falling into excavations include:

installing guard rails or covers on trench shields installing fencing around the excavation providing clearly defined pedestrian detours, and backfilling the excavation as work progresses.

2.4 Elevated timber floor or concrete slab from which a person could fall Occasionally concrete floor slabs and more commonly timber framed ground floors may be elevated and present a fall risk.

The risk of falling should be identified and appropriate controls used (for example, scaffolding, edge protection, etc).

2.5 Standing/erecting the walls for the ground floorsThis may only present a serious risk if the ground floor is elevated. Refer to section 2.8 of this Code for further information.

2.6 Installing floor joists/beams for the first and second floorsThe setting out, placing and fixing of floor joists should be done by working from access equipment set up on the floor below. Access equipment may include mobile scaffolds, trestle scaffolds, platforms with legs, stools and ladders.

Where a step ladder is used on the floor below to gain access, the ladder should be tall enough avoid standing on the top two treads.

Figure 2: Installing ceiling joists or upper level floor joists.

2.7 Installing flooring sheets at the first and second floor levelsLaying flooring is a task that potentially exposes workers to the risk of both internal and external falls and therefore the risk of falling between the floor joists or from the edge of the structure, should be identified and appropriate controls used (for example, scaffolding, edge protection, etc). Similarly, stairwells and voids should be protected prior to laying the floor.


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Access Safe access should also be provided to the area where the floor is being laid. Access should be restricted to only those workers who are laying the flooring.

Risk of falling through the floor frame It is good practice for the laying of floor sheets to begin adjacent to an internal or external access point. This provides some initial fall protection for workers.

Once an initial platform has been established by the first sheet, it is recommended that the laying of sheets proceed from this point in a systematic manner and in compliance with the applicable Safe Work Method Statement (SWMS). This effectively extends the platform until the full floor is in place.

Where strip flooring is to be installed, temporary sheet flooring (or example plywood sheeting) may be laid and secured as a temporary work platform that provides fall through protection.

Figure 3: Laying sheet flooring at upper level

Fall from edge of the structure Where the potential fall is reasonably likely to cause injury, adequate protection, such as edge protection, must be provided. This may be achieved using external scaffolding or guardrailing.

2.8 Standing/erecting the walls for the first or second floor levels

Provision of a work platform As working from open floor joists is an unacceptable work practice a solid platform should be constructed and used as a work area for the construction and/or erection of wall frames. In order to construct this platform flooring should be laid to avoid the joists being used for access.

Once sheet flooring or strip flooring has been laid and openings in the floor have been guarded, work on wall framing may commence.

Access to the floor should be restricted to those workers erecting the wall frames.

Edge protection


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Where the potential fall is reasonably likely to cause injury for persons constructing or erecting wall frames, edge protection should be installed prior to the construction and standing of exterior walls.

For window penetrations and balconies, ensure all open gaps and penetrations from which a person can fall are protected using methods such as:

specialized floor edge protection system timber railings installed at point of manufacture or on site guard railing system platform system, or full perimeter scaffold.

External wall frames used as edge protectionThis approach, where external walls are to be used as edge protection, may be appropriate where wall frames are built elsewhere and craned onto the floor in prefabricated form.

Prior to standing the frame, window and door openings in those external wall frames should be fitted with guardrails. Similarly, all braces and fixings must be prepared prior to raising the frames.

Figure 4: Erecting upper level wall frames

2.9 Loading the wall frame with trusses/roof framingThis section provides guidance on the installation of prefabricated timber roof trusses. Parts of this guidance may also apply to the installation of metal roof trusses.

Preparing for the lifting of roof trussesWhere practicable, roof trusses should be placed by crane on the wall top plates at the time of delivery. The truss erector, supplier and transporter should liaise to confirm the order in which the trusses are to be loaded onto the truck. Where possible, the trusses should be able to be unloaded at the site in the order that minimises the amount of handling by the truss erectors. When working at height, the erectors should be able to access the next required truss from the top of the truss


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stack.

It is important that relevant workers are consulted to ensure that any locations designated for the landing of trusses will not overload the wall frames. The manufacturer/supplier should provide the necessary detail and instructions for the installation of prefabricated timber roof trusses. Where trusses have not been landed directly onto the top plates, a safe system of lifting the trusses to the upper level needs to be developed. At no time should any worker stand on the top plate to receive roof trusses passed up from below.

The person erecting trusses should ensure that all wall frames are adequately braced to withstand loads during construction.

Lifting roof trusses If the size, weight and positioning of the roof trusses pose a risk to the health and safety of the person/s lifting trusses, then a crane with a certificated operator can be used to help undertake this task.

When cranage is required where erection height is too great or trusses are too large for manual handling the trusses can be craned into position, laid flat and suitably supported prior to erection. Where trusses cannot be self-supporting, use temporary props or internal walls for support (see Figure 5).

Figure 5: Method of supporting long trusses

2.10 Placing, standing and fixing trusses/rafters to create a roof frame

Preparation for the standing and fixing of roof trusses onto wall frame top plates At no time is any person to stand on or work from an external wall top plate without suitable fall protection.

The work required to place a truss into the correct location, stand it into the vertical position and then fix it into that position, can potentially create the risk of a fall either, into the structure or over the edge of structure. This process of placing, standing and fixing roof trusses may be undertaken from a platform such as scaffold planks supported on timber cleats, trestle ladders or a mobile platform providing that:

structural support for the planks complies with the appropriate good carpentry practice and any applicable standards


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where work platforms are used, they are a minimum of 450mm wide where there is no edge protection or other fall prevention device in place, a person should

not work closer than 1.5 metres from an external wall, including gable end walls, and no person is exposed to the additional risk of a fall into a stairwell or other void (i.e. a void

protection system should be installed).

Where trusses are used to support a person’s weight Truss bottom chords are considered a safe working area for a competent person if the conditions below are met. If the person erecting trusses is to walk or work from the bottom chords of the trusses, the following conditions should be applied:

trusses are adequately braced to stabilize the structure – bracing should be at a maximum of 3000mm apart if the bottom chord is used to support the person erecting trusses (see Figure 6)

Figure 6: ‘No go’ zone for persons erecting trusses

only a competent person is to work at heights footwear that provides good grip and support are worn a competent person or the truss manufacturer/supplier has provided the necessary detail

and instructions, including advice in regard to installers standing on the bottom chord, and the bottom chord is visually checked by a nominated competent person for defects that may

compromise the material's structural integrity (i.e. knots, splits, cracks and rotting timber) before walking on it. If a defect is found, rectification details should be obtained from the truss manufacturer and the person with control should be notified.

If the apex or other high bracing points cannot be reached, subject to a risk assessment and work method statement the following method can be used:

fix waling plates for standing or supporting temporary work platforms at the appropriate height to reach the apex or high points

the waling plate should be fixed to the face of the truss according to manufacturer's recommendations to ensure the load is transferred to the bottom chord

the waling plate can be used by the person erecting trusses to support temporary working platforms

the waling plate should be timber of 70 x 35mm F5, or equivalent, to a maximum of 1500mm long, fixed at each end by a minimum of two 65mm x 3.15mm nails (see Figure 7)


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Figure 7: Suggested method of fixing temporary waling plate

the web strut to support the waling plate should be a minimum 70 x 35mm F5, or equivalent, fixed at each end by a minimum of two 65mm x 3.15mm nails, and

waling plates should be erected in pairs every fourth truss, or as required, to enable adequate access to fixing points for bracing (see Figure 8).

Figure 8: Showing the positions for pairs of waling plates

Erecting first and second standard trussesThe person conducting a business or undertaking responsible for standing and fixing trusses should assess the team’s capability to handle the roof trusses.

Erect the first truss at the location specified by the roof manufacturer/supplier. This may be repeated a number of times for each common span series of trusses, depending on the roof layout design. Once the first and second trusses are fixed and temporarily braced, the bottom chord may be used for the person erecting trusses to stand on or to support temporary working platforms.

The person conducting a business or undertaking responsible for truss erection should consider the following:


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smaller trusses for single storey roofs can be separated from the pack and lifted individually into position along the top plates, or

if the truss needs to be repositioned, the person erecting the trusses should do this from below to avoid working at heights.

The person conducting a business or undertaking responsible for truss erection should place, stand, fix and brace the first and second truss in the following manner:

set up an appropriate working platform with a platform height not greater than 2 metres from the floor level at each end where the truss is to be fixed to the top plate

if a perimeter scaffold system is installed this work can be done from the outside rather than using internal working platforms or ladders

fix temporary braces to solid fixing points ready for connection to the truss. The braces can be timber of adequate size and length fixed by nails

fix skid blocks to top plate at first truss position to prevent the truss from slipping during standing

use a minimum of two people, one at each end, to stand the first truss; a third person may be required at mid-span to assist in stabilising a long span truss with a ‘v’ end push stick (see Figure 9)

Figure 9: Recommended method of manually standing trusses with a high apex

after standing the first truss to the vertical position, secure it to temporary braces. At this point, the first truss should be in a stable condition

erect the second truss using procedure above, and temporarily brace the second truss to the first truss.

The person conducting a business or undertaking responsible for truss erection should inspect the temporary bracing materials for obvious defects that may compromise the material's structural integrity (i.e. knots, splits, cracks and rotting timber).

Erecting subsequent roof trussesAdditional roof trusses should not be erected unless the prescribed fixing, bracing and any additional support requirements have been undertaken for the first and second truss.

Each subsequent roof truss should be placed with each end of the truss controlled by a person on the working platform or ladder. A third person at the apex may be required to assist.

Each subsequent roof truss should be fixed and braced according to the manufacturer’s/suppliers’ specifications using safe methods for working at heights.


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Fixing of top and bottom chord temporary bracingTemporary ties/bracing for roof truss erection should be fixed according to AS 4440 Installation of nailplated timber roof trusses. This standard requires that temporary ties be used on the top chords at spacings no greater than 3000mm and at spacing no greater than 4000mm on the bottom chord.

If the person erecting trusses is to be supported by the bottom cords of the roof trusses, the ties/bracing should be at spacings no greater than 3000mm.

All bracing and fixing should take into consideration all imposed loads during the course of construction. As such, flat strapping or an equivalent, or trimmers nailed to the face of trusses where the nailing is from the outer face of the truss, should not be used (see Figure 10).

Figure 10: Temporary bracing/ties to bottom chord of trusses. Note: Bracing to top chord similar

Erection of gable roof assembly and verge truss assembly This section covers the erection of gable roof assembly and verge truss assembly which includes diminishing trusses, verge trusses, verge trimmers and gable studs/droppers.

The erection should be done using appropriate safe work methods.

Note that where reasonably practicable, elements of the roof structure, such as a verge sprocket and outriggers, should be pre-assembled on the ground as a complete unit and lifted onto the supporting structure.

Erection of ancillary itemsGirder boots, hangers and the like should be installed to the manufacturer’s/suppliers’ specifications prior to working in the truss space.

Using a crane to lift and position domestic trusses (rare)The person conducting a business or undertaking responsible for truss erection should place, stand, fix and brace the first and second truss in the following manner:

set up an appropriate working platform with a platform height not greater than 2 metres from the floor level at each end where the truss is to be fixed to the top plate

if a perimeter scaffold system is installed this work can be done from the outside rather than using internal working platforms or ladders


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fix temporary braces to solid fixing points ready for connection to the truss. The braces can be timber of adequate size and length fixed by nails

guide the first truss into position while supported by the crane use a minimum of two people, one at each end, to fix the truss to top plates and to the

temporary braces. At this point, the first truss should be in a stable condition erect the second truss using the same procedure as above, and temporarily brace the second truss to the first truss.

Truss spacings of up to 600mm centres When trusses are erected at up to 600mm centres, persons working between the trusses to fix or brace them can use the erected trusses as a form of fall protection under controlled conditions.

Truss spacings of greater than 600mm centres In certain situations, the spacing of the truss may exceed 600mm centres, in which case other fall protection should be provided when working at heights to fix and brace the trusses. Such fall protection may include:

mobile scaffolding system complying with AS/NZS 1576 Scaffolding series and AS/NZS 4576 Guidelines for scaffolding

mesh or netting installed to the manufacturer's specifications fencing and handrails within adjacent trusses installed to the designer’s or manufacturer’s

specifications working platforms, elevating platforms, including motorised single person lift platforms

complying with AS 1418.10 Cranes, Hoists and Winches - Elevating work platforms, or planks placed across internal and external top plates and across the bottom chords of the

truss.

Constructing conventional or stick roof Once the ceiling frame has been securely fixed, the ceiling frame may act as a base to install a platform. Planks or sheet flooring plywood can then be used as a platform to pitch the roof. Where additional height is required above the platform on the ceiling frame, an additional platform may be erected.

When constructing a conventional roof, ceiling joists and hanging beams can be passed up internally through a stair opening or externally through the upper level wall frame when it does not expose the receiver to further risk.

Where ceiling joists are erected prior to pitching the rafters, the placement of the ridge beam, and the fixing of rafters to it, may be done from planks or a working deck placed on the ceiling joists. Where ceiling joists are not erected, a work platform will need to be provided for framers to work from.

The practice of roof carpenters balancing on a ceiling hanger while nailing ceiling joists to the hanger is to be avoided.

Framers working at the external wall should work internally from either scaffolding or ladders or from an external perimeter scaffold. A person can work from an external top-plate if fall protection measures are in place. An external working platform will also provide a work platform for tasks such as trimming rafters and installing eaves.

Where a bracket scaffold system is used, the wall frames should be braced as necessary to ensure adequate strength and to prevent excessive deflection. Scaffold planks may be used from waling plates or across bottom chords or top plates where necessary.

Where practicable, roofing members should be pre-cut at ground level.


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2.11 Fixing roof battens to trusses / raftersThe process for installation of the roof battens will depend on the types of roofing material that is to be installed. Although there are similarities in the methods used to install metal and tile roofing, there are also differences. Guidelines for the installation of roof battens for each type of roofing material are outlined below. For all roof work physical fall protection at the perimeter of the roof is required.

Roof battens need to be capable of supporting the expected loadings from installers.

In addition to the external fall prevention, batten and truss spacing should be reduced to minimise the risk of internal falls:

Batten where trusses are installed at 600mm centres or lessWhere roof trusses are installed and secured at spacings not exceeding 600mm centres the batten spacings should not exceeding 900mm centres.

If the trusses are installed at 600mm centres or less, a person may position the body so that the feet are on adjacent trusses at all times and walk to the apex of the roof in order to mark out measurements.

Batten where trusses are installed at 600mm to 900mm centresWhere roof trusses are installed and secured at spacings greater than 600mm but not exceeding 900mm centres, batten spacing should not exceed 450mm centres.

Batten where trusses are installed at greater than 900mm centres Where roof truss spacing exceeds 900mm centres and manufacturers/suppliers instructions permit, battens should not exceed 450mm centres.

Battens should also be installed sequentially and in a manner that controls the risk to installers, otherwise other fall protection should be used.

Trusses installed at greater than 600mm centres If trusses are at greater than 600mm centres, a person should not walk on the top chord of unbattened trusses unless internal fall protection is in place. Marking/setting out should be done sequentially throughout the batten installation process or by working from a ladder or work platform. If this is not a viable solution, internal fall prevention options such as internal catch platforms, or the use of planks across waling plates, internal top plates and bottom chords should be used.

Installation of battens Working off a ladder or a working platform, place the battens to be used on top of the trusses or pass/pull them up from the ground. Then secure the lower battens working from a ladder or internal or external work platform prior to roof access being required.

Secure remaining battens sequentially up to the apex of the roof by positioning the body over the truss (see Figure 11) making sure that there is at least one secured batten at waist level or above to minimise the risk of a fall.


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Figure 11: Fixing roof battens to trusses

Installation of Perimeter Battens – Metal Roofing Fastening of the perimeter battens to the hips and valleys may be done by affixing those parts of the perimeter battens which can be easily reached from a position on ladders or from inside the trusses. During the sequential battening of the body of the roof, the remaining length of the perimeter battens can then be secured.

2.12 Fixing fascias and gutters On houses with no eaves that have adequate fall-through protection in place, fascias and gutters may be installed by working from trestle scaffolds or ladders from inside the house frame.

Where the design involves eaves, an external platform should be provided for fascia and gutter installation work. Guardrailing should be fitted where the potential fall is reasonably likely to cause injury. If a gutter is not present, then the 100mm maximum distance of the platform from the roof face is measured from the fascia board.

2.13 Installing roof membrane

Roofing tasksRoofing work involves several tasks which potentially expose persons to the risk of falls both through and from the edge of the roof structure. Physical edge protection should be provided for work on a roof surface.

This section gives basic advice on the provision of fall protection for roofing construction work. This Code is not intended as complete guidance where the roofing work involves dismantling or demolition work.

Steep roofs where slope exceeds 35 degreesWhere the slope of a roof exceeds 35 degrees the roof is an inappropriate surface to stand on, even with guardrailing or a catch platform. In these circumstances, roof workers need a system to prevent sliding and to prevent falls from the perimeter, comprising two or more of the following:

a work positioning system a roof ladder, or a scaffold platform, located at the roof edge.


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Critical Angle The pitch of the roof is one of the key risk factors to be considered when determining the type of risk control measures to be put in place for roofing work.

The critical angle is the roof pitch below which is considered that roof workers may reasonably be able to work and walk across the roof. The critical angle can be taken as greater than

26 degrees, or 10 degrees where there is a likelihood of surface moisture, oil or other conditions makes

the roof slippery. Also give consideration to the fact that the critical angle may be reduced in the presence of fully glazed and wet tiles.

Persons conducting a business or undertaking should determine the critical angle as part of their risk assessment and use appropriate fall prevention measures to control the risk.


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4. TEMPORARY ACCESS AND EDGE PROTECTION Prior to commencing work ensure that all work areas have safe means of access and are free of obstructions.

Safe access systems must be provided for workers to access the upper floors and the roof to undertake work at those levels, for example, stairs incorporated into scaffolding or used as a part of a guard rail or platform system.

3.1 Guardrailing as edge protectionGuardrail systems should include top, mid and bottom rails or toeboards. Where toeboards are used in place of bottom rails they should be able to withstand the likely impact loads.

The design and testing should comply with the relevant Australian Standards and include the following:

toeboards or mesh infill to prevent tools, materials or debris falling from the roof, unless a 2 metre ‘no go’ zone has been established to prevent persons entering the area below

a clear gap between rails not exceeding 450mm the gap between the roof edge, including the gutter, and a guardrail located outside the roof

line shall not exceeding 100mm a clear distance between the roof cladding and the bottom rail of not less than 150mm and

not greater than 275mm an effective guardrail height above the roof surface of not less than 900mm (for roofs with a

pitch over 10 degrees the effective height should be measured from a point 300mm inside the roof edge)

infill panels where the pitch of the roof exceeds 26 degrees.

Floor edge protectionPersons should be able to access the roof through the roof edge protection without having to climb over the top rail or midrail or between the rails

Figure 12: Examples of upper floor edge protection


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Figure 13: Examples of upper floor edge protection

Edge protection around any holes or voids in the floor Regardless of the fall distance, where persons have to access upper level floor platforms, all holes such as stairwells, atriums and voids should be either—

sheeted over with a properly designed cover and a “Danger: Void below” sign, or guarded using guardrailing that is compliant with applicable standards.

The edge of these holes must be guarded as soon as the hole is created, as illustrated in Figure 14.

Figure 14: Void at upper level guarded


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Any coverings or temporary floors and their supports should be of robust construction capable of withstanding impact loads from any potential falls.

Roof edge protectionPersons should be able to access the roof through the roof edge protection without having to climb over the top rail or midrail

Figure 15: Guardrail systems for roofing work

3.2 Catch platforms on scaffolds and hanging bracketsCatch platforms may be constructed on scaffolding or hanging bracket systems (see Figure 16) and may be used to control the risk of a fall where the following applies:

the roof pitch is not greater than 26 degrees, the catch platform should be positioned as close as feasible to the underside of the roof, and in no case greater than 1 metre below the roof edge

the pitch of the roof is greater than 26 degrees, the catch platform should be positioned as close as feasible to the underside of the roof and in no case more than 500mm below the roof edge


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catch platforms must be fitted with a guardrail, the top rail should be located at an effective height of not less than 900mm above the point where the roofline projection intersects the guardrailing, with midrails installed at 450mm spacings

where there is an increased risk of falling due to slippery roofing materials (such as fully glazed tiles), the platform should be positioned not more than 500mm below the roof edge, regardless of roof pitch

where a platform is located more than 500mm below the roof edge, then additional means of access to the roof should be provided

platforms below the eaves should be extended to finish not more than 225mm from the building face or be fitted with edge protection on the platform’s inner edge, and

platforms should be kept clear of equipment, materials and debris.

For further information about the protection components refer to AS/NZS 4994 Temporary edge protection series.

Figure 16: Catch platforms for roofing work

3.3 Bricklayer’s heavy duty trestles For low level brick work, a bricklayer’s heavy duty trestle may be used with ladder access. Edge protection is not required if a risk assessment indicates that injury due to a fall is unlikely and the surrounding area is clear earth.

3.4 Hanging brackets incorporating edge protection A bracket scaffold with at least two planks and guardrailing is suitable for fascia/gutter installation work (see Figure 17) or suitable as edge protection if the requirements of catch platforms is complied with.

The scaffold should be erected from within the structure, so that the upper level wall frame provides fall protection for the erectors.

Other controls for fixing fascia and gutters may include perimeter scaffolds (for two storey construction) and elevated work platforms.


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Figure 17: Fixing gutters using a typical bracket scaffold

3.5 Ladders Ladders are primarily a means of access and egress. Many falls take place when people are working from ladders. In addition, when using a ladder:

the working width and movement is limited the time involved in moving and setting up ladders is often underestimated when planning

work the working position on ladders is often uncomfortable (the need to stretch sideways, work

above shoulder height and stand on narrow rungs for a long time) and may cause musculoskeletal disorders.

For these reasons, you should consider whether an elevating work platform or scaffolding would be safer and more efficient.When a ladder is used, check that:

the ladder is in good condition—the ladder should be inspected for faults, such as broken rungs, stiles and footing before it is used

damaged ladders are removed from service the ladder is on firm, stable and level ground the ladder is the correct height for the task to avoid reaching or stretching the ladder is not too close or too far from the support structure—the distance between the

ladder base and the supporting structure should be about one metre for every four metres of working ladder height (4:1 ratio)

the ladder is secured against displacement (i.e. slipping or sliding) and/or there is another person holding the base of the ladder

the ladder is not placed so that the weight of the ladder and any person using the ladder is supported by the rungs

all the locking devices on the ladder are secure materials or tools are not carried while climbing the ladder—use a tool belt or side pouch only light duty work is undertaken while on the ladder, where three points of contact can be

maintained and tools can be operated safely with one hand slip resistant base, rungs or steps are provided slip resistant shoes are worn


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ladders are not used without additional appropriate precautions:o in access areas or next to doorso on scaffolding or an elevating work platform to get extra heighto next to power lines unless the worker is trained and authorised and the appropriate

ladder is being usedo in very wet or windy conditionso next to traffic areas unless the working area is barricaded.

Further guidance on the safe use of ladders is available in the Code of Practice: How to Prevent Falls in the Workplace.


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APPENDIX A – OTHER RELEVANT INFORMATION

Codes of Practice Code of Practice: How to Prevent Falls in the Workplace Code of Practice: Managing Risks in Construction Work

Australian Standards (At the time of publication, the Australian Standards referenced in this appendix are current. Users of this document should ensure that the referenced standard has not been updated or replaced.)

AS 1418.10(Int) Cranes, hoists and winches - Elevating work platforms AS/NZS 1576 series Scaffolding AS 4440 Installation of nailplated timber roof trusses AS/NZS 4576 Guidelines for scaffolding AS/NZS 4994.1 series Temporary edge protection

Other relevant documents National Construction Code of Australia, published by the Australian Building Codes Board


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preventing falls in housing construction - safe … · web viewwhere roof trusses are installed and...

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