How to brief a commercial roof refurbishment tender

Give every bidder the same description of the building, evidence of the roof condition and rules for working on site. Ask for a common base price with options and exclusions shown separately. That makes it easier to tell whether a cheaper tender reflects a different roof specification, a different access plan or a cost that has been left out.

Open the printable roof tender checklist and use it to record what you already know and what needs confirming before you issue the brief.

Give bidders the same starting information

Identify the site, roof areas, approximate sizes, building use and the problem you need the project to solve. Mark where leaks appear and include dates, conditions and past repairs if available.
Share roof plans, available surveys, existing build-up, warranties and details of gutters, outlets, rooflights, plant and existing or proposed Solar PV. Mark any areas the survey could not access. See what to ask for in a commercial roof condition survey.
Provide relevant asbestos information and agree what further investigation is needed before work disturbs the building fabric. See the HSE guidance on asbestos surveys.

Set out which parts of the building need to stay in use

State where vehicles load, where staff and visitors enter, which areas contain sensitive stock or equipment and when a shutdown is possible. Ask each bidder to explain its proposed sequence, temporary weather protection and the access and site protection included in the price. Give tenderers the same assumptions for any areas that cannot be opened up before award. The HSE roof work guidance covers the need to plan safe access and manage fragile surfaces.

Ask for a price you can compare

Commercial roof tender comparison
Item	What to ask for
Roof system	Which layers and details are included, what stays, and who designs the junctions and interfaces.
Access and protection	What is allowed for, where the bidder expects clear working zones, and any costs associated with shutdowns or out-of-hours work.
Unknown conditions	Which sums are provisional, what triggers a variation and how additional work will be priced and approved.
Handover	Which inspections, drawings, warranties and maintenance information are included and who will issue them.

If you want to compare an overlay with a full replacement, ask for the same access, protection, rooflight and drainage assumptions in both prices. See our roof repair, overlay and replacement guide for the differences in scope.

Check the details that affect other trades

Roof-to-wall junctions, existing rooflights, drainage and PV can all change the scope. At Arcadia House in Southampton, the project photos show how slates, solar panels and an upper wall meet on a single roof slope. Ask the tenderer to identify who owns comparable interfaces on your building and where a drawing or site check is still needed.