When evaluating commercial roofing proposals, the total contract price is important, but it does not tell the entire story. Roofing projects often encounter unexpected conditions, repairs, design changes, or scope adjustments after work begins.
One of the best ways for commercial property owners to control costs is to request unit prices as part of every roofing bid.
Unit prices establish agreed-upon costs for specific items of work before those items are needed. They help reduce disputes, simplify change orders, and provide transparency when conditions differ from the original scope.
What Are Unit Prices in a Roofing Bid?
A unit price is a predetermined cost for a specific quantity of work or material.
Instead of negotiating pricing after a problem is discovered, the contractor provides a fixed rate for potential additional work.
Examples:
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Cost per square foot of roof replacement
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Cost per linear foot of flashing replacement
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Cost per sheet of damaged decking replacement
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Cost per drain replacement
Unit prices allow owners and contractors to quickly calculate additional costs if conditions change.
Why Should Commercial Roofing Bids Include Unit Prices?
Roofing projects frequently involve hidden conditions that cannot always be identified before demolition begins.
Examples include:
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Wet insulation
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Damaged roof decking
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Deteriorated flashing
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Hidden leaks
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Structural repairs
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Additional penetrations
Without unit prices, unexpected work can lead to:
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Delayed negotiations
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Higher costs
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Project disputes
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Unclear change order pricing
Including unit prices creates a more predictable process.
Essential Unit Prices to Request in Every Roofing Bid
The exact unit prices depend on the roofing system and project scope, but commercial property owners should consider requesting the following items.
1. Roof Membrane Replacement Cost
Request pricing for additional roof membrane installation.
Include:
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Cost per square foot
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Material type
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Thickness
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Installation method
Examples:
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Additional TPO membrane
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Additional PVC membrane
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Additional modified bitumen
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Additional coating system
This helps if the project area expands.
2. Roof Insulation Replacement Cost
Insulation damage is common when existing roofing systems are removed.
Request unit prices for:
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Insulation removal
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New insulation installation
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Different insulation thicknesses
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Wet insulation replacement
Important details include:
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Insulation type
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R-value
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Board thickness
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Disposal requirements
3. Roof Deck Replacement Cost
Roof decking repairs are one of the most common unexpected expenses.
Request pricing for:
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Plywood replacement
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Metal deck replacement
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Concrete deck repairs
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Structural deck repairs
Unit pricing should identify:
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Material type
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Thickness
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Labor included
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Disposal included
4. Flashing Replacement Cost
Flashing failures are a major source of commercial roof leaks.
Request unit prices for:
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Base flashing
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Counterflashing
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Wall flashing
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Curb flashing
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Penetration flashing
Pricing may be provided:
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Per linear foot
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Per penetration
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Per detail
5. Drain and Drainage Repairs
Proper drainage is critical for commercial roofs.
Request pricing for:
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New roof drains
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Drain replacements
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Scupper repairs
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Overflow drains
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Drain extensions
Poor drainage can significantly reduce roof life.
6. Penetration Repairs and Flashing
Commercial roofs often contain:
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HVAC units
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Pipes
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Electrical conduits
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Exhaust fans
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Equipment curbs
Request unit pricing for:
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Small penetrations
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Large penetrations
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Equipment curb flashing
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Pipe boots
7. Roof Coating Application
For restoration projects, request coating unit prices.
Include:
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Cost per square foot
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Coating thickness
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Primer requirements
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Surface preparation
Examples:
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Additional silicone coating
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Additional acrylic coating
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Additional elastomeric coating
8. Sheet Metal Work
Metal components often require replacement during roofing projects.
Request unit prices for:
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Coping metal
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Fascia metal
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Gravel stops
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Drip edges
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Expansion joints
Pricing may be provided per linear foot.
9. Temporary Repairs and Emergency Work
For active leak situations, request pricing for:
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Temporary roof repairs
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Emergency leak response
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Protective coverings
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Water intrusion mitigation
This helps owners respond quickly without renegotiating costs.
10. Labor Rates for Additional Work
In addition to material unit prices, request hourly rates for unforeseen work.
Include:
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Roofing labor rate
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Foreman rate
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Sheet metal worker rate
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Equipment operator rate
This provides clarity for work that cannot be priced by unit.
How Unit Prices Should Be Presented
A good roofing bid should clearly identify:
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Unit description
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Measurement method
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Material specification
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Labor included
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Equipment included
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Disposal included
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Warranty impact
Example:
Replace damaged insulation: $___ per square foot, including removal, disposal, new insulation installation, and manufacturer-approved materials.
Clear descriptions prevent disagreements later.
Unit Prices and Change Orders
Unit prices make change orders easier because the cost basis has already been established.
For example:
During roof replacement, the contractor discovers 2,000 additional square feet of damaged insulation.
If the bid includes:
“Replace damaged insulation: $3.50 per square foot”
The additional cost can be calculated immediately:
2,000 sq. ft. × $3.50 = $7,000
This reduces delays and eliminates unnecessary price negotiations.
Should the Lowest Unit Prices Always Be Selected?
No.
The lowest unit price is not always the best value.
Owners should evaluate:
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Material quality
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Contractor experience
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Warranty impact
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Installation standards
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Long-term performance
A very low unit price may indicate excluded work or lower-quality materials.
Frequently Asked Question
Which unit prices should be requested in every roofing bid?
Every commercial roofing bid should include unit prices for common unknown conditions and potential changes, including roof membrane replacement, insulation replacement, deck repairs, flashing replacement, drainage repairs, penetration flashing, roof coatings, sheet metal work, temporary repairs, and additional labor rates. Requesting unit prices helps commercial property owners compare proposals accurately, manage change orders, and avoid unexpected costs during construction.
For commercial roofing projects, detailed unit pricing creates transparency, improves budget control, and helps ensure a smoother project from bidding through completion.
Related Questions
- How do you price unforeseen deck replacement fairly?
- What documentation should accompany every change order request?
- What allowances are typical for deck replacement in a bid?
- What is the difference between a time-and-materials and lump-sum change order?
- What are bid alternates and how should they be structured?
- How do I evaluate a bid that is dramatically lower than the others?
- Should I always choose the lowest bid for a commercial roofing project?
- What does “scope of work” mean in a roofing quote?
