A commercial roof tender should explain the work required, the conditions contractors will encounter and what needs to be included in each tender response.

For example, requesting a “commercial roof replacement” does not establish whether insulation is being replaced, gutters are included, existing flashings can remain or mechanical plant needs to be temporarily removed.

The following information gives tenderers a stronger basis for assessing the project.

Project and roof details 

Provide the property address, building type and the roof areas included in the tender. 

Where available, include current roof plans, drawings, photographs, maintenance records and previous inspection reports. If documents are old or  existing conditions have not been confirmed, make that clear. 

For existing metal roofs, useful information includes the roof profile, approximate age, insulation and previous repair history. 

Known defects 

Identify leaks, corrosion, damaged sheets, failed flashings, deteriorated sealants and drainage issues already known to the project team. 

Recent photographs can be particularly useful when theyshow both the defect and its location on the roof. 

Unknown conditions should be marked for site verification rather than left for each contractor to interpret independently. 

Roof access and site conditions 

Explain how the roof can be accessed and how materials may be moved to the work area. 

Include relevant loading areas, car parks, restricted zones and known limitations affecting cranes, scaffolding or elevated work platforms. 

Where access methodology has not been determined, contractors can be asked to propose an appropriate approach. 

Business operations 

Commercial roofing often takes place while the property remains operational. 

Warehouses may need loading areas available for dispatch. Retail buildings may require controls around customers and tenants. Industrial facilities can have production schedules, restricted areas and plant movements that affect the work sequence. 

Include these constraints in the tender so contractors can account for them when proposing staging and access. 

Roofing materials and drainage 

Where a roofing profile, finish, insulation system or product specification has already been selected, provide it to every tenderer. 

If the roofing system has not been finalised, ask contractors to identify what they are proposing. 

The drainage scope should also be defined. Depending on the project, this may include gutters, box gutters, sumps, outlets, overflows and downpipes. 

Roof drainage design and installation may involve requirements under AS/NZS 3500.3:2025 along with project specific design and regulatory requirements. 

Penetrations and roof mounted services 

Identify existing vents, skylight, ducts, pipework, mechanical equipment and solar equipment where known. 

The tender should  clarify whether the roofing contractor will flash around existing penetrations and who is responsible for removing, disconnecting or relocating plant. 

Clear responsibility between roofing, mechanical, electrical and other trades can prevent scope gaps during construction. 

Safety and contractor requirements 

Include site specific requirements such as inductions, exclusion zones, pedestrian controls, lifting operations and interaction with other trades. 

Queensland WHS requirements classify construction work involving a risk of a person falling more than two metres as high risk construction work. A Safe Work Method Statement is required before this work is carried out. 

Tender requirements may also include relevant QBCC licence information, insurance, SWMS, product documentation and project specific compliance information. 

Metal roof and wall cladding work may involve AS 1562.1:2018, along with applicable NCC requirements, engineering specifications and manufacturer installation requirements.