Avoid unexpected, expensive surprises when you replace your worn out commercial roof. By knowing the variable costs in a commercial roofing system replacement, you can ask the right questions to get a more accurate idea of the project cost.

atlantacommercialroofingcontractors.com gathered information about commercial roof replacement, what aspects of the project are variable in cost, what you can expect to spend on a new roofing system, and some of the available commercial roofing types.

Commercial Roofing System Replacement

The replacement of a commercial roofing system is a rare event for building owners and managers. When a roof is installed and maintained correctly, it can last for decades before needing replacement.

The following information will help you reach an informed decision about how to project roof replacement cost variables, and which type of roofing system to install:

Commercial Roof Accessibility

When replacing your commercial roof, access to your property and the roof can impact project costs as much as the roof type. Consider the following:

Commercial Building Height – Roof replacement for a 2-story commercial building will be much less costly than a 10-story commercial building. This is due, in part, to the need for cranes to remove old roofing material and lift new material to the work area.

Access to Building Property – Property access also has an impact on the project. The ability to freely move equipment to the property near the building will influence the logistics and project cost.

Material Storage Areas – Material storage is also a determining factor. Large “lay down” areas near the building facilitate the logistics of the roofing project and can lower its cost.

Building Occupant Safety – Building occupancy can pose a series of challenges to the roofing project. The safety and productivity of the building’s occupants must be considered at all times. If this requires roof replacement activities to occur after regular business hours, additional costs will likely be added to the project.

The easier it is to access your roof, execute the removal of the old roof, and install the new commercial roofing system, the less costly the project will be.

Commercial Roof Substrate Condition

Roof replacement costs can be heavily influenced by the condition of the substrate material. A commercial roof substrate may be composed of:

• A concrete, wood, or metal deck
• Plywood or cover board
• Insulation

Damages to the substrate must be repaired before roof replacement. This cost is a variable, as even the most experienced roofers with the best detection technology may not identify substrate damages until the old roofing materials are removed.

Local, Regional, and State Commercial Roofing Code Requirements

The location of your commercial building may make your roofing system subject to code requirements, including more robust fasteners at more frequent intervals, insulation, substrate, ventilation, and/or slope requirements.

An example of this would be commercial structures along the coast of Florida. Codes in these areas require commercial roofing systems to be designed to withstand higher wind loads. For these roofing systems, more durable fasteners at closer intervals would be required, increasing the cost of the roof replacement project.

Commercial Roof Load-Bearing Capacity

Another crucial factor in determining the cost of replacing your commercial roofing system is the calculation of its dead, live, and transient load capacity.

Calculating your roof load capacity is one of, if not the most crucial aspect when determining the construct of the roof’s substrate and selection of a roofing system. Your roof must be able to support its projected dead load (HVAC units, ducts, vents, exhaust units, etc.), live load (installers, repairmen, and technicians), and transient load (rain, wind, and snow).

Read more about commercial roof loads at atlantacommercialroofingcontractors.com/what-is-commercial-roof-load-why-you-need-to-know/

Commercial Roofing Types

No two roofs are the same. Thus, there are several commercial roofing systems to choose from. The following are some of the more popular commercial roofing types, installation information, and typical price range:

TPO, PVC, and EPDM Single-Ply Membrane Systems Can Cost from $3.50 to $8 per square foot

TPO, PVC, and EPDM are all known as single-ply roofing systems, they require fewer installation steps and are installed with a straightforward process:

• The old roofing system is removed
• The substrate is cleared of anything that may damage the selected membrane
• The membrane is rolled out onto the roof
• The membrane is then adhered to the roof using tape, glue, or heat (for thermoplastic material)
• The membrane is also adhered to itself where its edges overlap
• Protrusions are sealed

The time it takes to install a membrane, or single-ply roofing system also depends on the width of the membrane. The wider it is, the fewer seams there are to seal in the roofing system, which also leaves fewer opportunities for leaks and eventual substrate damage.

A BUR/Asphalt System Can Cost from $5 to $9 per square foot

Built-up roofing systems are among the oldest in modern times. BUR systems are durable and effective at resisting leaks while repelling water. The installation process occurs in the following steps:

• The old roofing system is removed
• Base sheets are laid down and attached to the roofing deck
• Felt is then glued to the base sheets using an adhesive, concrete, asphalt, or tar
• Gravel or cap sheets are installed over the felt
• A top layer of asphalt completes the installation

A BUR system creates a robust roof, able to keep severe weather and the elements from entering the building it protects.

A Metal Roofing System Can Cost from $5 to $14 per square foot

One of the most long-lived roofing options (forty + years), metal roofing is also one of the more expensive options. The following details how a metal roofing system is installed:

• The existing roof is removed
• The roof deck is built/prepped (framework and insulation installation)
• The flashing and eaves are installed
• Metal panels are laid out and fastened to the roof deck (fastening depends on which material the panels are composed of; aluminum, copper, steel, etc.)

Metal roofing comes in panels or steel shingles. Steel shingles are installed in the same manner as slate, clay, or concrete shingles.

A Modified Bitumen System Can Cost from $4 to $8 per square foot

Modified bitumen is a result of the evolution of asphalt roofing. It is a form of membrane flat roofing. The system is durable and can sustain substantial foot traffic without wear. The following is the installation processes of a “torch-down” modified bitumen roofing system:

• The existing roof is removed
• The substrate is cleared of any debris
• Heavy roofing felt is rolled out and nailed down
• Flashings and primer are installed
• The first sheet is rolled out along the edge of the roof for trimming and fitting
• The sheet is then rolled back up
• A torch is used to slightly melt the bitumen as the first sheet is rolled back out
• Overlapping sheets are then applied in the same manner until the roof is covered and sealed

Before selecting modified bitumen, verify that the existing substrate is compatible. Improper adhesion can lead to leaks and likely failure of the new modified bitumen system.

Disclaimer: The preceding price ranges are for comparative purposes only and should not be considered a part of any bid or quote for roofing installation, repair, or replacement.

Replacing Your Commercial Roofing System

In this article, you discovered information about replacing a commercial roofing system, the variables involved in calculating the cost, and commercial roofing types with their price ranges.

By knowing what to look for in a commercial roofing replacement estimate, you can avoid surprises by asking informed questions about installation variables.

When you choose to rely solely on a contractor’s bid or estimate, you may be in for a surprise when unforeseen damages and difficulties cause your roofing project to go quickly over budget.

Sources:
asphaltroofing.org/bur-multi-ply-built-up-roofing/
roofcalc.org/metal-roofing-prices/
nrc.gov/docs/ML1214/ML12146A122.pdf

See Commercial Roof Replacement for the first version of this content.

Don’t let the wrong roofing system or a poorly installed one cripple your business. Knowing what goes into installing or replacing a commercial roof will help you make informed decisions when it is time to act.

atlantacommercialroofingcontractors.com gathered information about commercial roof installation, replacement, and answers some common commercial roofing FAQs.

Commercial Roofing System Installation

Installing a roof on a new commercial building or replacing an old one may seem procedurally simple enough. However, some roofing system installation differences should be addressed.

TPO, PVC, and EPDM Membrane System Installation

Also known as single-ply roofing systems, these systems require fewer steps and are installed with a relatively straightforward process:

1. The roof is cleared of any material that may damage the membrane
2. The membrane is rolled out onto the roof (single-ply roofing material typically comes in rolls)
3. The membrane is then adhered to the roof using tape, glue, or heat (for thermoplastic material)
4. The membrane is also adhered to itself where its edges overlap
5. Protrusions are sealed

The time it takes to install a membrane or single-ply roofing system will also depend on the width of the material. The wider the material is, the fewer seams in the roofing system, which also translates to fewer opportunities for leaks and roof failure.

Elastomeric Coatings and Spray Polyurethane Foam (SPF) System Installation

Both Mesh Reinforced Elastomeric Coatings (MREC) and SPF coatng systems are intended to extend the life (up to 20 years) of an existing roofing system. Their installation includes:

Mesh Reinforced Elastomeric Coatings (MREC) – Composed of acrylic, elastomeric, and polyester reinforcing mats, MREC mats are applied in multiple layers until the desired thickness is reached.

Sprayed Polyurethane Foam (SPF) – SPF coatings may be acrylic, polyurethane, silicone, aggregate, or mineral granules. SPF coatings are sprayed onto a roof and should be applied by skilled workers.

• SPF can be applied directly to the roof deck or existing roofing system
• An SPF membrane is created by spraying a two-part liquid material onto the substrate
• The mixture expands and solidifies creating a waterproof polyurethane foam

Besides the protective nature of SPF coatings, the thickness and slope of the roof can be controlled during application.

BUR/Asphalt System Installation

Built-up roofing systems are among the oldest roofing processes in modern times. BUR systems are durable, they look nice, and are effective at resisting leaks and repelling water. The installation process occurs in four steps:

1. Base sheets are laid down and attached to the roofing deck
2. Felt is glued to the base sheets using adhesive, concrete, asphalt, or tar
3. Gravel or cap sheets are then installed over the felt
4. A final layer of asphalt completes the installation process

A properly installed BUR system creates a virtually impenetrable roof, able to keep severe weather and the elements from getting into the building it protects.

Modified Bitumen System Installation

Modified bitumen is an evolution of asphalt roofing that is a form of membrane flat roofing. The roofing system can sustain substantial foot traffic without wear. The following are the installation processes of torch-down and peel-and-stick modified bitumen roofing systems:

Torch-Down Modified Bitumen

1. The roof is cleared of debris
2. Heavy roofing felt is installed and nailed down
3. Flashing and primer are installed
4. The first sheet is rolled out along the edge of the roof (trimmed and fitted)
5. The sheet is rolled back up
6. A torch is used to slightly melt the bitumen as the sheet is rolled back out
7. Overlapping sheets are applied in the same manner until the roof is covered and sealed

Peel-and-Stick

1. The roof is cleared of debris
2. Heavy roofing felt is installed and nailed down
3. Flashing and primer are installed
4. The first sheet is rolled out along the edge of the roof (trimmed and fitted)
5. The sheet is rolled back up
6. The protective film is removed to expose the adhesive and rolled into place
7. Sheets are overlapped by about six inches until covering the entire roof
8. The system is pressed into place using a weighted roller
9. The roof edges are sealed with roofing cement and rolled again to seal the layers together

Before installing modified bitumen, verify that the existing material on the roof is compatible (previous systems using rubber can be eaten away, causing weaknesses and potential failure of the new modified bitumen system).

Metal Panel Roofing System Installation

One of the most durable roofing options (up to forty years), metal roofing is also one of the more expensive options. The following detail how a metal roofing system is installed:

1. The existing roof may need to be removed (depending on municipal codes and/or roof load capacity)
2. The roof deck is prepared (framework and insulation installation)
3. Flashing and eaves are installed
4. Metal panels are laid out and fastened to the roof (how they are fastened depends on which material the panels are composed of; aluminum, copper, steel, etc.)

Metal roofing can be installed using panels or steel shingles. Steel shingles are installed the same way as slate, clay, or concrete shingles.

New Commercial Building Roofing System Installation

A commercial building’s roof is its primary defense against damaging weather and natural hazards. Architects, builders, and building owners decide early in the designing stages which roofing system will be installed. Some of the factors that lead to a decision are:

• What equipment will be installed on the roof
• What is the needed roof load
• What type and how many protrusions will be needed (vents, exhaust pipes, skylights, drains, etc.)
• How and where will the roof shed water
• What is the expected foot traffic on the roof (walkways and reinforcements may be required)
• What is the anticipated lifespan of the roofing system
• Which commercial roofing system offers the best performance for future building activities (the roof used for an office building may not serve that used for a restaurant)
• Regional weather patterns (wind, rain, snow, hail, ice, and heat)
• Natural disasters (tornadoes, hurricanes, wildfires, earthquakes, etc.)

Many regions across the country experience one sort or another of natural disasters or recurring weather events. In many cases, these regions have developed laws or ordinances that require specific materials to be used when installing a new commercial roofing system.

Read more about what a commercial roof load is at atlantacommercialroofingcontractors.com/what-is-commercial-roof-load-why-you-need-to-know/

Replacing A Commercial Roofing System

For building managers, replacing a commercial roofing system is a rare event to see in one’s career. A well-installed and maintained roofing system can last decades before needing replacement.

When it comes time to replace the roof on your commercial building, the following steps will help you hire the right contractor to install the right roof for your building’s needs.

Bidding Process: Request bids from at least 3 contractors. By doing so, you can compare their prices, suggestions, more importantly, their work history, quality, and online reviews.

Roofing System Selection: The roofing system you select should accommodate the structure and purpose of your commercial building. An honest, professional roofer will help you determine which roofing system will serve your building best and advise you whether or not replacement is necessary.

Selecting a roofing system for your commercial building will require you to determine the best fit for your building, which system fits within your budget, which one offers the best protection and durability, and which maintenance program makes the most sense.

Roofing System Tear Off: If your current roof has reached the end of its life, it must be removed before installing a new one. This process exposes any flaws or defects in the roofing deck, which must be addressed before installing a new roof.

Roofing System Installation: Since every roofing installation is unique, a definitive installation timeline is difficult to project. The following should be taken into consideration when determining how long your installation will take:

• Roof deck repair (if required)
• The type of commercial roofing system
• The size of the roof (the larger the roof, the longer it will take)
• Unexpected weather events

Sometimes, when a permit is required to replace your roof, there may be stipulations that affect how and when the work can be done. To avoid delays, fines, and further punitive measures, permit requirements must be adhered to at all times.

Roofing System Guarantees, Warranties, and Maintenance Programs: Once your roofing system installation is complete, you should receive a:

• Guarantee covering the installation of your roof
• Warranty covering parts and materials
• Maintenance program proposal from your roofer to periodically perform inspections and minor repairs

Read more about what goes into a commercial roofing maintenance program at atlantacommercialroofingcontractors.com/maintenance-programs-services/

Commercial Roofing System FAQs

The following are answers to common FAQs based on general roofing information. Since no two commercial roofing systems are exactly alike, your specific situation may require further investigation for a more accurate response.

Question: How long will a commercial roofing system last?

Answer: A well-installed and maintained commercial roofing system can last from 30 years to the life of the structure it protects. The longevity of a roof depends mostly on the quality of its materials, installation, and maintenance program.

Question: My roof is leaking, what should I do?

Answer: Immediately contact your roofer. Whether you have a maintenance program or not, leaks must be addressed immediately to prevent structural damage to the roofing system and building.

Question: What is the difference between a commercial and residential roof?

Answer: Similar roofing systems can be applied to both commercial and residential structures. However, most commercial roofs will require a higher roof load to support HVAC and other equipment. They may appear very similar but are structurally different.

Read more about why you need to know your commercial roof load at atlantacommercialroofingcontractors.com/what-is-commercial-roof-load-why-you-need-to-know/

Commercial Roofing System Installation Process

In this article, you discovered information about new commercial building roof installation, commercial roofing replacement, and answers to common roofing questions.

By knowing what is involved in the commercial roofing installation or replacement process, you can make informed decisions when it’s time to select a roofing contractor and the best roofing system for your commercial building.

Not knowing what to do when you need a new roof can lead to the wrong roof installed, possible municipal code violations, expensive fines, and continuous roofing maintenance problems.

Sources:
wbdg.org/guides-specifications/building-envelope-design-guide/roofing-systems
buildings.com/article-details/articleid/4937/title/the-basics-of-roof-maintenance
asphaltroofing.org/bur-multi-ply-built-up-roofing/
whysprayfoam.org/spray-foam/roofing-systems/
amtrustfinancial.com/getmedia/7d774cf7-d8f4-455f-8b0d-a0d03a1c23fb/IBHS-Commercial-Roof-Best-Practices-Guide.pdf

See Commercial Roof Installation for the first version of this content.

Don’t let wet spots on your ceiling or streaks down your wall make your property look ugly and worth less money. Your leaky roof is often times the result of a failure in the roofing system’s flashing.

Without sufficient flashing, a roofing system cannot repel the elements, will ultimately fail and begin to leak. When installing a new roof or repairing a current one, it is essential that the flashing be compatible with the roofing system and be installed properly.

atlantacommercialroofingcontractors.com examines the purpose, types, and application of flashing used in commercial roofing systems.

What Is Flashing?

Flashing is a layer of waterproof material that keeps water from penetrating your roofing system at joints, vents, exhausts or appliance connection points. While caulk is used to fill small gaps around doors and windows, it has an entirely different purpose, and shouldn’t be confused with flashing.

Water naturally runs downhill to the lowest point of gravity. For flashing to work correctly, all seams must be installed facing downhill. Properly installed, the upper edge of flashing should be covered or protected by tarpaper, TPO, or whichever membrane or material is used in the roofing system.

Flashing Material

Numerous materials can be applied as flashing. The two criteria commonly used when determining which material to use are:

1 – The material won’t degrade from being in contact with other incompatible material.

2 – The material is impermeable to water.

The following materials are commonly used as flashing in both commercial and residential roofing systems:

Plastic and Rubber – While primarily used as caulk, plastic and rubber are excellent water-repellants when applied as flashing.

PVC and TPO – Both PVC and TPO are popular types of roofing systems, and the same material can be used as incredibly effective and durable flashing.

Roofing Felt – Asphalt-saturated roofing felt can be used as flashing, but is not as durable as other options.

Aluminum – Durable, easy to form, and somewhat inexpensive. When left in contact with alkaline material like concrete, or treated lumber, aluminum flashing will corrode.

Galvanized Steel – Not as durable as other options, but it is very inexpensive.

Copper and Lead-Coated Copper – More difficult to bend and form than aluminum, but much more durable. Copper flashing is typically used during the installation of solar panel piping, wiring and sensor connections.

Lead – Because of its super-flexibility and durability, lead is a popular choice in the roofing industry (a favorite of masons for chimney flashing). There are potential health risks, but the use of lead flashing continues, and when properly installed can last for up to 200 years.

While most flashing is sold in rolls that vary in thicknesses and can be cut, bent, and shaped at the job site. Pre-molded flashings are also available for standard-sized exhaust pipes, vents, and fittings.

Flashing Types for Roofing Systems

The following are the names and descriptions of different types of flashing used in commercial and residential roofing systems:

Ridge Flashing – This flashing is applied at the “peak” of a dually sloped roof.

Bargeboard – This is the flashing along sloped roof edges.

Wall Abutment – This is where roof edges meet walls.

Corner Flashing – This flashing is used where walls meet, and it runs from roof to floor.

Inverted Corner Flashing – This flashing is used when the corner of a structure meets a wall. Instead of wrapping around the corner as in “corner flashing,” it is applied to the structure and the wall in an “inverted corner” from roof to floor.

Eaves Flashing – This flashing runs along the length of flat edges of a roofing system.

Drip Cill Flashing – This is the flashing which runs along the lower perimeter (at the foundation).

Valley Flashing – The point where two downward slopes meet is where valley flashing is applied.

Step Flashing – Commonly used in place of wall abutments or chimney and skylight flashing (on slopes), step flashing is the downward overlapping alternate layering of roofing and flashing material.

Metal Edge Flashing – Also known as “drip edge flashing,” this is installed around the perimeter of a roofing system to direct the flow of water off of it without entering the structure . To learn more about commercial edge flashing and coping visit disastersafety.org/ibhs/commercial-roofs-flashing-coping/

Saddle Flashing – This is the flashing used where joists meet walls or other support structures, wrapping around connection points to form a water-tight seal.

Vent Pipe/Exhaust Flashing – This flashing provides a water-tight seal at the point where vent or exhaust pipes protrude through a roof.

Cap Flashing – This flashing is usually composed of metal and is used to shield the upper edges of membrane base flashing along the top of a wall or column.

As you can see, flashing is a critical element in a roofing system. There are a few more essential components that comprise a complete roofing system. To learn these, and for more commercial roofing information and tips, visit atlantacommercialroofingcontractors.com/info/

Roof Flashing Weatherproofs Your Structure

Don’t let your building unnecessarily look run-down and develop water damage from preventable water infiltration and leaks. Keeping the elements outside is what a successful roofing system does, and it dramatically relies on properly applied flashing.

In this article, you discovered what roofing system flashing is, what it is used for, the different types, and its application.

The use of the wrong flashing material on a roofing system may lead to leaks and its ultimate failure. Save money and avoid unexpected interruptions of your business by having the appropriate flashing material properly installed in your commercial roofing system.

Sources:
http://web.mit.edu/parmstr/Public/NRCan/CanBldgDigests/cbd069_e.html
https://www.nachi.org/flashing-part1-12.htm

See Types and Purpose of Commercial Roof Flashing for the first version of this content.