Direct Answer
A commercial re-roof proposal and scope of work should clearly define what is being replaced, how the work will be performed, what materials and systems will be used, what is excluded, how existing conditions will be handled, and what documentation and warranties the owner will receive at completion.
A strong proposal should allow the property owner, facility manager, developer, general contractor, or board to compare proposals on an equivalent scope rather than simply comparing the total price. The scope should be specific enough to identify the roof system, tear-off requirements, substrate preparation, insulation, membrane, flashing, drainage, penetrations, edge details, safety requirements, cleanup, warranty requirements, and closeout documentation.
For commercial projects, manufacturer submittal packages can include product data sheets, flashing details, specifications, certifications, system approvals, SDS documentation, and guarantee information. These documents should be coordinated with the actual project scope rather than relying on a generic proposal. Johns Manville Commercial Roofing Submittal Wizard provides an example of the type of technical documentation commonly assembled for a commercial roofing system.
Who This Applies To
- Commercial property owners
- Property and facility managers
- Commercial real estate investors
- Developers and asset managers
- General contractors
- Construction managers
- Condominium and HOA boards
- Owners’ representatives
- Procurement teams evaluating commercial roofing bids
Not for: This is general commercial roofing procurement guidance. Project-specific design, engineering, code compliance, wind-uplift requirements, product approvals, and warranty requirements should be confirmed by the appropriate design professional, manufacturer, authority having jurisdiction, and qualified roofing contractor.
1. Identify the Project and Existing Roof
The proposal should begin by clearly identifying the property and existing roof conditions.
Include:
- Property address
- Building or roof section
- Approximate roof area
- Existing roof system
- Existing membrane type, if known
- Existing insulation and cover board, if known
- Existing deck type, if known
- Number of roof levels
- Known rooftop equipment
- Known leaks or problem areas
- Whether the work covers the entire roof or specific sections
The proposal should make it clear what portion of the property is actually included in the contractor’s price.
2. Clearly Define the Re-Roof Scope
The scope should state exactly what work will be performed.
For example:
- Existing roof removal
- Partial or complete tear-off
- Existing membrane removal
- Insulation removal or replacement
- Cover-board installation
- Deck preparation
- New membrane installation
- Flashing replacement
- Edge-metal installation
- Drain and scupper work
- Curb and penetration detailing
- Walkway installation
- Roof-access improvements
A proposal should not simply state “install new commercial roof.” It should explain what the contractor is actually providing.
3. Specify the Roof System
The proposal should identify the proposed roofing assembly instead of naming only the membrane.
Depending on the project, identify:
- Roof membrane type
- Membrane thickness
- Insulation type and thickness
- Cover board
- Attachment method
- Adhesives or bonding materials
- Fasteners and plates
- Seaming method
- Base sheets or underlayments where applicable
- Flashing materials
- Edge-metal system
- Walkway materials
Manufacturer technical documentation should be coordinated with the specified system. Johns Manville, for example, provides commercial roofing submittal packages containing product data, flashing details, specifications, certifications, system approvals, SDS documentation, and guarantee information. View the Johns Manville commercial roofing submittal resources.
4. Define Tear-Off Requirements
One of the most important parts of a re-roof proposal is identifying exactly what happens to the existing roof.
The scope should state:
- What existing materials will be removed
- Whether removal is full or partial
- How many existing roof layers are included
- How removed materials will be handled
- Whether insulation will be removed
- How exposed areas will be temporarily protected
- How the contractor will respond to concealed conditions
If the contractor is pricing an overlay rather than a complete tear-off, that distinction should be explicit.
5. Explain Deck and Substrate Conditions
The proposal should explain how the contractor will handle deteriorated or damaged substrate discovered after the existing roof is removed.
Address:
- Deck inspection
- Wet insulation
- Damaged insulation
- Corroded metal deck
- Deteriorated wood deck
- Structural concerns
- Replacement-unit pricing
- Owner authorization requirements
It should be clear whether deck replacement is included in the base price or treated as additional work.
6. Define Insulation and Energy Requirements
If new insulation is part of the re-roof system, specify the type, thickness, number of layers, attachment method, and required thermal performance.
Where applicable, the proposal should also identify:
- Existing insulation to remain
- New insulation requirements
- Cover-board requirements
- Tapered insulation
- Crickets or saddles
- Drainage improvements
- Thermal-performance requirements
The final assembly should be coordinated with the applicable project specifications and code requirements rather than treating insulation as an unspecified allowance.
7. Address Flashings and Penetrations
Many commercial roof failures occur at transitions, penetrations, edges, and other details, so the proposal should clearly define the flashing scope.
Identify treatment for:
- Parapet walls
- Roof-to-wall transitions
- Pipe penetrations
- HVAC curbs
- Equipment supports
- Skylights
- Expansion joints
- Drains
- Scuppers
- Roof edges
- Metal counterflashing
The contractor should reference the applicable manufacturer’s installation details and project specifications rather than leaving critical flashing details undefined. Johns Manville specifically provides installation guides and flashing details as part of its commercial roofing technical resources. View commercial roofing contractor resources.
8. Define Drainage Work
The proposal should explain whether existing drainage components will remain, be repaired, or be replaced.
Address:
- Roof drains
- Drain strainers
- Scuppers
- Gutters
- Downspouts
- Overflow or secondary drainage
- Drain flashing
- Tapered insulation
- Crickets and saddles
If the project includes drainage modifications, those modifications should be clearly identified rather than buried in a general “roof repairs” allowance.
9. Include Edge and Perimeter Details
The proposal should identify how roof edges and perimeter conditions will be addressed.
Include, where applicable:
- Metal coping
- Edge metal
- Fascia
- Drip edges
- Termination bars
- Parapet details
- Perimeter securement
- Wind-uplift requirements
Florida projects may have additional requirements depending on the property’s location, roof system, building characteristics, and applicable code or product approvals. The proposal should therefore identify the applicable approved assembly rather than simply stating a generic fastening pattern.
10. Identify Wind-Uplift and Product-Approval Requirements
For Florida commercial re-roofing, the proposal should address applicable wind-uplift design requirements and required product or assembly approvals.
Depending on the project, documentation may include:
- Approved roofing assembly
- Wind-uplift rating
- Fastener and plate requirements
- Attachment pattern
- Perimeter and corner enhancements
- Product approvals
- Manufacturer installation requirements
Manufacturer evaluation reports and Florida approval documents can specify the approved assembly, deck type, attachment method, and wind-uplift performance. For example, Florida roofing approval documentation identifies system components and maximum design pressures for approved assemblies. See an example of Florida roofing assembly approval documentation.
11. Define Rooftop Equipment Coordination
The proposal should identify how existing rooftop equipment will be handled during the re-roof.
Address:
- HVAC units
- Electrical equipment
- Exhaust fans
- Solar equipment
- Equipment curbs
- Pipes and conduits
- Equipment supports
- Temporary relocation
- Reinstallation
It should be clear which trade is responsible for disconnecting, moving, supporting, and reconnecting equipment.
12. Include Temporary Weather Protection
A commercial re-roof exposes the building to weather during construction. The scope should explain how the contractor will protect the building when the permanent roof is not yet complete.
Address:
- Daily dry-in procedures
- Temporary closures
- Weather monitoring
- Emergency protection
- Protection of occupied areas
- Protection of equipment and contents
- Responsibility for water intrusion caused during construction
13. Define Safety and Building-Operations Requirements
For occupied commercial buildings, the proposal should explain how roofing work will be coordinated with building operations.
Include requirements concerning:
- Roof access
- Fall protection
- Material staging
- Crane operations
- Noise
- Odors
- Tenant access
- Parking and loading areas
- Working hours
- Weekend or night work
- Emergency access
14. Identify Inclusions and Exclusions
This is essential for comparing competing proposals.
The proposal should explicitly identify what is included and excluded.
Potential exclusions include:
- Structural repairs
- Extensive deck replacement
- HVAC relocation
- Electrical work
- Asbestos or hazardous-material abatement
- Major masonry repairs
- Interior repairs
- Unexpected concealed conditions
- Permit fees, if excluded
- Engineering fees, if excluded
An exclusion should not be hidden in fine print when it could materially change the final project cost.
15. Explain Allowances and Unit Prices
If concealed conditions are expected, the proposal should establish how additional work will be priced.
Useful unit prices may include:
- Roof deck replacement per square foot
- Insulation replacement per square foot
- Additional membrane work per square foot
- Flashing replacement per linear foot
- Drain replacement per unit
- Equipment curb work per unit
- Structural repairs based on documented field conditions
This makes change-order pricing more transparent than simply stating that unforeseen work will be billed on a time-and-materials basis.
16. Include Schedule and Project Duration
The proposal should state the anticipated construction schedule.
Include:
- Estimated mobilization date
- Expected start date
- Estimated duration
- Work sequencing
- Daily working hours
- Weather-related assumptions
- Owner access requirements
- Major milestones
The schedule should also explain circumstances that could reasonably affect completion, such as severe weather, material availability, concealed conditions, or required inspections.
17. Define Quality-Control and Inspection Requirements
The proposal should identify how installation quality will be monitored and documented.
Depending on the project, this may include:
- Manufacturer inspections
- Independent roof observation
- Daily installation documentation
- Seam inspections
- Fastener verification
- Moisture testing
- Final inspection
- Punch-list correction
For systems requiring manufacturer review or inspection, the proposal should identify those requirements before work begins.
18. Specify Warranty and Guarantee Requirements
The proposal should clearly distinguish between the contractor’s workmanship warranty and the manufacturer’s system warranty or guarantee.
Identify:
- Manufacturer
- System warranty or guarantee type
- Warranty term
- Contractor workmanship warranty
- Inspection requirements
- Warranty exclusions
- Owner maintenance obligations
- Transferability
Manufacturer requirements should be reviewed before installation because certain guarantees may require specific inspections, approved contractors, installation procedures, or documentation.
19. Include Cleanup and Disposal
The scope should identify how the contractor will handle removed roofing materials and daily cleanup.
Include:
- Debris removal
- Dumpster requirements
- Material disposal
- Daily housekeeping
- Magnetic nail or fastener cleanup where applicable
- Protection of landscaping and property
- Final site cleanup
20. Define Closeout Documentation
A commercial re-roof proposal should state what the owner will receive at project completion.
A strong closeout package may include:
- Final inspection report
- Manufacturer warranty or guarantee
- Contractor workmanship warranty
- Product data
- As-built roof plan, where applicable
- Photographic documentation
- Permit documentation
- Final invoices
- Maintenance recommendations
- Roof-access information
- Emergency contact information
Keeping this documentation in the building’s permanent roof file makes future maintenance, insurance reviews, warranty claims, and capital planning easier.
21. Require a Clearly Defined Price
The proposal should show the total contract price and identify exactly what that price covers.
Where applicable, identify:
- Base contract amount
- Alternates
- Allowances
- Unit prices
- Taxes
- Permit costs
- Inspection costs
- Mobilization costs
- Potential change-order conditions
Owners should compare proposals based on equivalent scope, not simply the lowest initial number.
22. Include Payment and Change-Order Terms
The proposal should explain payment milestones and how changes will be authorized.
Define:
- Deposit requirements
- Progress payments
- Retainage, if applicable
- Final payment conditions
- Change-order authorization
- Documentation required for additional work
- Payment timing
Change orders should identify the additional work, cost, and schedule impact before the work is performed whenever reasonably possible.
23. Compare Proposals on Scope, Not Just Price
Before selecting a contractor, compare each proposal against the same checklist.
| Item | Proposal A | Proposal B | Proposal C |
|---|---|---|---|
| Roof system specified | Yes/No | Yes/No | Yes/No |
| Tear-off scope | Defined/Unclear | Defined/Unclear | Defined/Unclear |
| Insulation scope | Defined/Unclear | Defined/Unclear | Defined/Unclear |
| Flashing scope | Defined/Unclear | Defined/Unclear | Defined/Unclear |
| Drainage scope | Defined/Unclear | Defined/Unclear | Defined/Unclear |
| Deck repairs | Included/Excluded | Included/Excluded | Included/Excluded |
| Warranty | Defined/Unclear | Defined/Unclear | Defined/Unclear |
| Closeout documents | Defined/Unclear | Defined/Unclear | Defined/Unclear |
| Total price | — | — | — |
Bottom Line
A good commercial re-roof proposal should answer five questions clearly: What is being replaced? How will it be installed? What is included and excluded? What will it cost? What documentation and warranty will the owner receive?
The scope should specifically identify the roof assembly, tear-off, substrate preparation, insulation, membrane, flashing, drainage, edge details, rooftop equipment coordination, weather protection, safety requirements, quality control, cleanup, warranties, schedule, exclusions, allowances, change orders, and closeout documentation.
For Florida projects, the proposal should also be coordinated with applicable code requirements, approved roofing assemblies, manufacturer requirements, and project-specific wind-uplift requirements. Manufacturer technical documentation can be particularly important when verifying approved assemblies and installation details. Johns Manville’s commercial roofing submittal resources and Florida roofing approval documentation illustrate the type of technical information that may need to support a roofing system.
Related Questions
- What should a GC look for in a commercial roofing subcontractor bid in Florida?
- What roofing submittals should a GC expect from a commercial roofing subcontractor?
- How should a GC evaluate roofing value-engineering proposals without increasing water-intrusion risk?
- What is a pre-installation roofing conference, and why does it matter?
Sources
- Johns Manville — Commercial Roofing Submittal Wizard
- Johns Manville — Commercial Roofing Contractor Resources
- GAF — Florida Building Code Roofing Assembly Evaluation Report
- GAF — Florida Building Code Liquid-Applied Roofing Systems Documentation
Last reviewed: October 2026
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Need Commercial Roofing Help?
ShieldLine Roofing can help commercial property owners, developers, facility managers, and general contractors evaluate re-roof scopes, compare proposals, coordinate commercial roofing work, and plan documentation through project closeout.
Disclaimer: This information is provided for general educational purposes and is not legal, engineering, architectural, insurance, code-compliance, or construction-contract advice. Project-specific requirements should be confirmed with the appropriate design professional, authority having jurisdiction, manufacturer, and qualified commercial roofing contractor.
Commercial Roof Replacement & Re-Roofing
