The True Cost of a Commercial Roof

How much does it cost to replace or repair a commercial roof? It can be hard to get a clear answer from roofing companies, and this can be very frustrating. As a facilities manager or a building owner, roofing is an investment in your building, and you need to know the numbers and understand them. 

At GIDEON, our experts have been doing commercial roofing for the last 20 years, all across the United States - and we have pricing down to a science. 

In the next few paragraphs, we’ll show you the components that go into the price of a commercial roof and help you get an accurate estimate of your costs with an easy-to-use table.

How Do You Determine a Commercial Roof’s Price?

Seven factors determine the price of a commercial roof: 

1. The size and complexity of the roof
2. The type of roofing system
3. Insulation type
4. Roof location
5. Tear-off and disposal
6. Warranty length
7. Project Timeline

Roof Size & Complexity

As you’d expect, the larger the roof, the more material and work you need to complete it, and your final roof cost is usually quoted in price per square foot.  

The slope of the roof also comes into play, as steeper slopes are more dangerous and may demand higher-skill labor or special equipment. A flat roof (often called a “low-slope roof” because it does have a pitch for drainage, just not a noticeable one) is much easier to work on and may be less expensive than a steep-sloped roof the same size. Fortunately, the vast majority of commercial roofs are flat.

“Penetrations” are another significant factor. A penetration is anything that sticks up through the roof's surface, like an HVAC unit, skylight, or vent. Contractors have to install the roof around these components, which (in single-ply roofing) usually involves cutting the membrane to fit and then sealing the seams. 

If you have a unique roof shape or unusual architectural features, your job might need custom materials and installation methods, which will also raise the price. A complex roof design might also demand a more elaborate drainage system, with additional drains or scuppers (holes cut through parapet walls on flat roofs to allow water drainage).

Ease of roof access is also essential. If a roof requires additional equipment, like cranes or lifts, to access, your project will be more expensive. The area available for staging may also make a difference. Staging expenses in a dense downtown with limited adjacent space will be more expensive than staging in an industrial park with large parking lots.  

Roof Type

The type of roofing system you choose will make a big difference in the project's final cost, as every system varies in quality & performance, installation requirements, and manufacturing costs. 

Single-ply systems like TPO, PVC, and EPDM - the most popular roofing choices due to high performance and ease of installation - can range anywhere from $3-$15 per square foot, depending on whether you're doing a simple re-cover or a full tear-off. While all these systems are relatively easy to install, TPO is the least expensive regarding the membrane itself, which runs around 65 cents per square foot, while EPDM and PVC run about 90 cents per square foot and $1.10 per square foot, respectively. The installation method, however, is the most significant factor affecting the price of these systems, with “mechanically attached” being the least expensive and “fully adhered” being the most expensive. Check out our complete guide to TPO roofing to learn more about single-ply installation methods.

Roof foam and coatings, a popular choice for restoring and extending the life of an existing roof, often runs from $2-$8.50 per square foot. These can be an excellent way to save money and double the lifespan of an existing roof.

Metal roofs typically range from $3-$18 per square foot, also depending on whether you're coating, removing and replacing, or doing a "retrofit" where you install a new system on top of an existing one. Factors that affect the price include the type of finish, the panel type, and the gauge or thickness. Acrylic finishes are cheaper, while Kynar (a special thermoplastic coating) is more expensive. Regarding panels, standing seam panels are more expensive, and R-panels (also called “exposed fastener” panels) are less expensive. As expected, the thicker the metal gauge, the more expensive. Higher numbers are thinner, and lower numbers are thicker, so 24 gauge is thicker and more costly, and 29 gauge is thinner and cheaper. 

Built-Up roofing, an old system that was the go-to commercial roofing choice for over a century, generally costs between $3.50-$20 per square foot and is usually more expensive due to the labor involved in building up multiple layers of asphalt. 

Modified bitumen (a more advanced type of asphalt roof similar to single-ply) usually settles around $6-$20 per square foot. Granulated modified (a system with small rocks embedded in it to protect it from the sun, like a shingle) is the most common. Like single-ply systems, the installation method affects your price substantially, with "torch-down" the most expensive and "cold-applied" the least.

Insulation

Insulation is a huge factor in roofing costs that contractors and customers often overlook when estimating a job. Insulation is the X-factor between a cheap bid and an expensive one; It dramatically affects the price. There are six types of insulation commonly used in commercial roofing:

 

Material	What It Is	Average Price Per Sq. Ft.
Fiberglass Batts	Fine-glass fibers, typically used to insulate walls, floors, and ceilings in residential construction.	$0.30
Expanded Polystyrene (EPS)	Rigid foam board made from polystyrene.	$0.30
Extruded Polystyrene (XPS)	Rigid foam board made from polystyrene.	$0.40
Polyisocyanurate (polyiso)	Rigid foam board made from isocyanate and polyol (like spray foam but a hard board)	$0.70
Spray Foam Roofing	Fluid-applied isocyanate and polyol	$1.20

Insulation is an essential factor, as the kind you choose can substantially impact your HVAC costs. Spray foam roofing, for instance, can help you save substantially compared to foam boards. Ultimately, which insulation you choose depends on your application, budget, and investment goals.

Roof Location

Location can impact price in multiple ways, from differences in regional labor costs to material availability, to weather conditions, to building codes and permitting fees. 

Your climate, for example, might influence the selection of materials and installation methods. If you live in an area with temperature extremes, you may want to invest in more energy-efficient roofing materials and insulation to keep the building temperate and your bills low. Weather can also make working conditions more challenging for contractors, leading to higher labor costs.

Local building codes can also determine the type of roofing material and installation techniques used. Some municipalities may mandate that your roof meet certain fire resistance, wind resistance, or energy efficiency criteria, which could require specialized materials or extra components. Permitting and inspection fees also vary by local jurisdiction.
 
Local market conditions may also substantially affect your price. Labor may be more expensive in populated areas with a high cost of living. In rural areas, labor is usually cheaper, but the cost of materials and transportation may be higher. 

Tear-Off and Disposal

Do you need to tear off your roof? Hopefully not. Legally, you can have two roof systems on the same building, so you can simply build on top of your existing roof. Another excellent option is a roof coating system, which can restore and extend the life of your current roof for a substantially lower price than a new single-ply system. But suppose neither of these options is feasible. In that case, you will incur the additional cost of tear-off and disposal, which usually includes additional labor costs, disposal fees, and a container rental. 

Tear-off and disposal will add $2-$4 per square foot on average, depending on how many layers you have to remove and the type of your existing roof system. Asphalt roofs are generally more expensive, while single-ply systems are less expensive.

Warranty Length & Type

The length of the roof warranty chosen will also influence the cost of your roof. Longer warranties have a higher upfront cost but can give peace of mind and protection against future roof concerns. Shorter warranties may save money upfront, but they may not provide the same degree of protection. You should choose warranty length based on the use of the building and your investment timeline. If, for example, you only plan on occupying a building for another ten years, a cheaper system with a shorter warranty may make more sense. 

To learn about warranties in detail, check out our Guide to Commercial Roof Warranties.

Generally, a 10-year warranty will add 6-10 cents per square foot to your price, a 15-year warranty will add 15-25 cents per square foot, and a 20-year warranty will add 17-30 cents per square foot.

Project Timeline

How quickly do you need to complete your project? If you need it within a tight window, you may pay a premium for the additional labor needed to meet your deadline. A much longer timeline, however, may also mean higher costs, as it typically indicates a more labor-intensive project.

Calculate Your Roofing Price

How much can you expect a roof solution to cost from GIDEON? We’ve put together a helpful table below to give you an idea of what your roof solution might cost. We’ve broken it down by roof system and job type. 

 

	Repair (Total Job Cost)	Restore (Per Square Foot)	Re-Cover (Per Square Foot)	Re-Roof (Per Square Foot)
Roof Coating	$650-$3.5K	$2-$5	$5.5-$12	$3.5-$8.5
Spray Foam Roofing	$650-$5K	$2.5-$6	N/A	$8-$18
TPO	$650-$4K	$3-$5.50	$5.5-$12	$6.5-$18
PVC
EPDM
Metal	$650-$2.5K	$2.75-$5.50	$6.5-$12.5	$6.5-$18
Modified Bitumen	$650-$7K	$3.5-$6	$5.5-$12	$12-20
Built-Up Roofing
Built-Up Roofing with Gravel	$650-$8,500	$6.50-12.00	$6-$12	$12-$22
Solar Roof	$1K-$20K+	$3-$6.50	$8-$17	$10-$25