Temporary Fencing Tender Considerations in New Zealand

Temporary fencing is commonly treated as a minor Preliminary and General item, often priced as either a rate per metre or a lump sum for the project duration.

That approach is acceptable only if the underlying scope has been properly considered.

The actual cost is influenced by installation, monthly hire, screening, bracing, signage, relocations, dismantling, damage, loss, programme changes and the extent to which the fence layout changes through construction.

A competent tender allowance should therefore treat temporary fencing as a temporary works and site establishment item rather than simply applying a metre rate to the site perimeter.

1. Establish the fencing scope before pricing it

The starting point should be a staged take-off.

The tenderer should identify:

• initial perimeter length
• maximum perimeter length
• changes in layout during construction
• internal exclusion zones
• temporary interfaces with public areas
• staged handovers
• gates and access points
• screened versus unscreened lengths
• likely relocation requirements

Temporary fencing is normally priced either as: a rate per metre or a lump sum for the required scope. For longer or more complex projects, the commercial build-up should still be understood internally even where the tender submission presents only a lump sum.

A practical cost build-up is:
Initial installation + monthly hire + scrim + bracing + signage + relocations + damage/loss risk + final dismantle

The purpose of this exercise is not necessarily to expose every component to the Principal. It is to ensure that the contractor understands what sits behind its tendered allowance.

2. Installation, monthly hire and final dismantle should be considered separately

For hired fencing, the commercial components are generally:

• delivery
• installation
• monthly hire
• dismantle
• collection

The initial installation usually includes distribution of panels, feet, clamps, braces and establishment of the required perimeter. Monthly hire then continues for the period the equipment remains allocated to the project. Final dismantle and collection are separate costs. This distinction matters because a contractor may tender the fencing as a lump sum while the supplier continues charging on a monthly basis. The tenderer therefore needs to understand the programme duration it is pricing against and carry an appropriate project risk allowance within its margin. 

Programme overruns are generally a contractor risk unless the contract provides entitlement to additional time and associated cost. Where an Extension of Time is granted for a qualifying event, temporary fencing may form part of a subsequent prolongation assessment. A tenderer pricing that prolongation should remember that the original tender may already have included contingency and margin for normal programme risk. Pricing a prolongation variation at pure net supplier cost can therefore understate the contractor’s true commercial position, depending on the contract terms and how the original risk was priced. The correct treatment will depend on the specific contract, causation and valuation provisions, but the tenderer should understand the distinction between:

ordinary programme risk carried in the tender

and

additional cost arising from an event giving contractual entitlement to an Extention of Time (EoT) and associated prolongation / cost.

3. Site moves are frequently underestimated

Temporary fencing rarely stays in one position for an entire civil or commercial project.

Common reasons for relocation include:

• earthworks staging
• services installation
• pavement construction
• temporary haul roads
• changing access arrangements
• landscaping
• partial handovers
• public interface changes
• establishment of new work fronts

Industry practice is generally to charge a site move as:

Callout + dismantle + install

even where both occur during the same visit.

This is because the supplier still has to:

• dismantle the existing fence
• remove or redistribute feet and braces
• relocate panels
• re-establish the new line
• re-brace the installation
• reposition gates
• restore the system to a usable condition

A tenderer should not assume that an original installation rate includes unlimited future moves. For staged projects, this should either be estimated within the lump sum or recognised as a project risk within the tender margin. There is also a commercial difference between a programmed site move and an unplanned callout. A planned relocation of a long fence line during normal site operations is different from asking a supplier to return specifically to move a small section because access is unexpectedly required.

4. Scrim selection should be based on site conditions

Scrim should not be specified simply as a default percentage across every project.

The required product should reflect:

• visual obscurity required
• public interface
• client presentation requirements
• dust-generating activities
• environmental exposure
• site wind conditions
• project location
• duration of installation

The cost impact of scrim is wider than the material itself. Higher blockout generally increases wind loading on the fence and can therefore increase:

• bracing frequency
• ballast requirements
• installation labour
• maintenance
• failure risk
• repair requirements

A low-blockout product may be suitable where the primary requirement is basic screening. A higher-blockout product may be appropriate where the Principal requires stronger visual separation from the public or where the site is highly visible. However, a highly exposed coastal, elevated or open site may require substantially more bracing than a sheltered urban site.

The correct tender question is therefore not:

What scrim rate should I allow?

It is:

What level of screening is actually required, and what temporary fencing system is required to support it?

Dust generation

Scrim can assist with general visual containment and reduce some movement of light debris, but it should not be relied upon as the principal dust-control measure.

Where the works generate significant dust, separate controls may still be required, including:

• water suppression
• misting
• sweeping
• local extraction
• work sequencing
• stockpile management
• wheel wash or road cleaning

The tenderer should therefore avoid paying for very high-blockout scrim solely on the assumption that it will remove the need for other dust controls.

5. Bracing should reflect what is attached to the fence

An unscreened mesh fence behaves very differently from a fence carrying scrim, banners, solid signage or sound barriers.

Attachments increase the effective wind area and therefore increase loading.

The tender should consider:

• scrim blockout percentage
• sign size
• sign spacing
• banners
• branded mesh
• acoustic barriers
• fence height
• exposed corners
• open ends
• topography
• surrounding buildings
• prevailing wind exposure
• associated risk level based on expected pedestrian and vehicular traffic

A common estimating error is to price fencing first and then add scrim and signage later without increasing the bracing allowance.

The more appropriate sequence is:

screening/signage requirement -> exposure -> bracing requirement -> installed cost

Large solid signs deserve particular consideration because they can introduce concentrated wind loads into individual panels.

Where significant signage is required, additional bracing or independent sign support may be more appropriate than relying on the temporary fence alone.

6. Signage requirements should be identified during tender

Temporary fencing commonly becomes the mounting surface for site signage.

Tenderers should establish whether the project requires:

• site identification boards
• Principal branding
• contractor branding
• emergency information
• hazard boards
• PPE signage
• traffic or pedestrian directions
• environmental notices
• restricted-access signage
• stakeholder information
• specific project signage

These requirements can create costs for:

• sign manufacture
• installation
• replacement
• relocation
• additional bracing
• ongoing maintenance

The project specification, Principal’s Requirements, SSSP, CMP and CTMP should be reviewed together.

Signage should not be treated as an isolated branding item where it affects temporary works loading or site access arrangements.

7. Damage and theft should be treated as a normal project risk

Damage to temporary fencing is common.

Panels are installed around active construction operations and are frequently exposed to:

• excavators
• trucks
• loaders
• cranes
• deliveries
• demolition works
• earthworks
• repeated relocations
• public interaction
• third-party subcontractors

Typical damage includes:

• bent panels
• broken welds
• damaged feet
• missing clamps
• damaged gates
• broken braces
• cut scrim
• damaged signage

Theft also requires a realistic allowance.

Temporary fencing is particularly exposed because it sits around the site perimeter, is generally easier to access than materials stored within the site, is portable and can be readily resold or reused. These characteristics make it a more attractive target than equipment requiring specialist removal or identification.

Theft risk is generally higher where:

• the site is isolated
• vehicle access is easy after hours
• perimeter lighting is poor
• neighbouring passive surveillance is limited
• the site is unattended
• sections of the perimeter are obscured
• there are no cameras

The contractor should therefore consider the expected exposure of the particular site rather than applying the same loss assumption to every project.

Under many construction contracts, particularly government and infrastructure contracts, responsibility for the Site and Temporary Works generally sits with the contractor during the period from Site possession through to Practical Completion, subject to the specific contract conditions.

Accordingly, theft or damage should not automatically be assumed to be recoverable from the Principal.

Unless there is a specific contractual entitlement, prior agreement or demonstrable Principal risk event, reimbursement may be difficult. The hire industry also allocates this risk to the contractor, and stolen gear will require reimbursement to the hire company.

The tenderer should therefore include an appropriate risk allowance in its margin rather than relying on recovery later.

8. Hire versus purchase should be assessed commercially

Hiring should not automatically be assumed to be the cheapest option.

The tenderer should compare hire and purchase based on:

• project duration
• total quantity
• number of relocations
• internal labour availability
• future project pipeline
• storage
• transport
• expected damage
• maintenance
• residual value

Hire provides lower upfront capital exposure and removes the need to store equipment after completion.

Purchase may become more attractive where:

• the programme is long
• the contractor expects repeated site moves
• internal labour can complete relocations
• the equipment can be reused on future projects
• there is a strong resale market
• the contractor has the excess cash on establishment to procure these items and claim against the schedule over the project duration

Purchase also allows the contractor to recover residual value by selling the fencing at completion, if not move these to the next project.

That residual value should form part of the commercial comparison.

9. Light-duty versus heavy-duty fencing when purchasing

Purchase decisions should not be based on panel price alone.

A typical light-duty panel may weigh around 10 kg.

A heavier commercial panel may weigh around 20 kg or more.

The heavier product generally contains:

• more steel
• stronger frame sections
• heavier welds
• greater resistance to repeated handling
• a more substantial galvanised coating

Galvanising thickness is particularly important.

The zinc coating protects the underlying steel and is progressively consumed over time.

A thinner galvanised coating generally provides a shorter corrosion life, particularly in:

• coastal environments
• high-moisture areas
• sites where panels are repeatedly scratched
• yards where panels remain outdoors
• projects involving repeated transport and handling

In practical fleet terms, a light-duty approximately 10 kg panel may provide around 2 to 3 years of commercial service under regular construction use.

A well-manufactured heavy-duty approximately 20 kg panel with a materially heavier galvanised coating may remain commercially serviceable for 10 years or more.

The relevant tender comparison is therefore whole-of-life cost, not simply initial purchase price.

10. Tenderers should review temporary fencing as a complete package

A competent temporary fencing allowance should consider:

The metre rate itself is rarely the main commercial risk.

The larger risks usually sit in:

duration, relocations, screening, bracing, damage, theft and programme performance.

A tenderer who understands those items can price temporary fencing properly even where the final submission shows only a single lump sum.

A tenderer who simply multiplies the perimeter by a monthly rate is relying heavily on the programme and site conditions remaining exactly as assumed.