Commercial Roof Replacement in Dallas: Planning the Project

What this page covers

This page is for owners and managers planning a full new roof on a business building. It explains the main choices and how to compare bids.

If you are deciding whether to tear off the old roof, see our recover versus tear-off guide. If you want to compare roof sheets, see our guide on TPO, EPDM, and PVC. For cost factors, see our commercial roof cost guide.

Start with your goals

Before you call anyone, write down what matters most to you. This makes bids easier to compare.

• How long do you plan to own the building?
• Do you want lower cooling bills?
• How long a warranty do you want?
• When can you spend the money?
• How much noise and disruption can the building handle?
• Are there tenants, customers, or patients inside every day?

Share this list with every bidder. Good roofers will shape their plan around it.

Test for hidden water first

Many old roofs hide water under the top sheet. Water soaks the foam boards below, which are called insulation.

A moisture survey finds these wet areas. It may use a meter, a heat camera at night, or small test cuts.

This step matters a lot. If the roof is mostly dry, you may have cheaper options, like adding a new roof over the old one. If it is wet in many places, the old roof likely needs to come off.

Tear-off or recover

A tear-off removes the old roof down to the deck. The deck is the hard floor of the roof.

A recover adds a new roof over the old one. It can save money and cut down on mess.

A recover may work when there is only one old roof layer, the foam is mostly dry, and the building can hold the extra weight. Building codes limit how many layers a roof can have. Roof makers also have their own rules.

Ask each bidder which one they suggest and why. Ask them to show the test results that support it.

Choosing the roof type

Many low-slope business roofs use one of a few roof types:

• TPO is a white sheet with seams melted together by heat.
• PVC is a sheet with heat-melted seams that handles grease and many chemicals.
• EPDM is a rubber sheet, often black but also white, with taped or glued seams.
• Modified bitumen, or mod-bit, comes in heavy rolls of asphalt mixed with rubber or plastic.
• Metal roofs use steel panels and are common on warehouses.

Carlisle, a maker of TPO, PVC, and EPDM, sells each in several ways to attach them. Ask for the product sheet for the exact roof that is being proposed.

How the roof is attached

There are three main ways to hold a roof sheet down:

• Fastened: screws and plates hold the sheet to the deck.
• Glued: the sheet is stuck down with glue.
• Weighted: gravel or pavers hold it in place.

Each way works differently in high wind. Each costs a different amount. Ask why the bidder picked one way for your building.

Fix drainage while you can

A new roof is the best time to fix water that sits on the roof. Water that sits for days is called ponding.

GAF, a large roofing maker, points to sloped foam boards, small ridges called crickets, more drains, and scuppers to move water off. Scuppers are holes in the low wall that let water out.

Tell bidders where water sits now. Ask how their plan will fix it.

Codes and the city

The City of Dallas lists its adopted building codes on its Know the Code page. As of the city's posting, these are the 2021 building codes with Dallas changes, in effect since May 12, 2023.

A new roof can trigger rules about foam board thickness and energy use. Ask your roofer or designer how the current code applies. If your building is outside Dallas, follow your own city's rules.

Working while the building stays open

Many businesses stay open during a new roof. That takes planning:

• Work in sections, so only part of the roof is open at a time.
• Seal each section at the end of every day.
• Plan where a crane or lift will go.
• Keep glue smells away from air intakes.
• Set quiet hours for offices, clinics, or hotels.
• Protect walkways and parking from falling debris.

Air intakes are vents that pull outside air into the building. Ask how the roofer will keep smells out.

How to compare bids

Ask every bidder to fill in the same items:

• Exact roof product and thickness
• How it is attached
• Foam board type, thickness, and slope plan
• Tear-off or recover, and why
• Price per square foot for wet foam that is found later
• Price per square foot for bad deck that is found later
• How the roof is sealed each night
• Who issues the warranty, how long it lasts, and what it covers

Hidden wet foam and bad deck are common surprises. Prices for them should be in writing before work starts.

Warranties

Commercial roofs often have two kinds of warranties. One comes from the roof maker. One comes from the roofing company.

Maker warranties often need an approved roofer and a final check by the maker. They may also require regular upkeep. Read the terms and keep a copy.

What drives the cost

We do not post prices. These are the main things that change the cost of a new commercial roof:

• Tear-off or recover
• Foam board and slope
• Roof type and thickness
• How it is attached
• Cranes, lifts, and access
• Working in phases or after hours
• Warranty level

Questions to ask a roofer

• What did the moisture test show?
• Why do you suggest tear-off or recover?
• What will you charge for hidden wet foam or bad deck?
• How will you keep the building dry each night?
• How will you fix where water sits now?
• Who issues the warranty, and what are its rules?

Good answers show the bidder has thought about your building, not just the roof.

Who should be on your team

A large new roof may need more than a roofer. Depending on the building, you may also want help from other experts.

A roof consultant can write the plan and check the work. An engineer can confirm the building can hold extra weight, which matters for a recover. Your air conditioning company may need to lift and reset units. A project manager can keep everyone on schedule.

For smaller buildings, the roofer may handle most of this. For larger ones, a team helps avoid costly mistakes.

Moving rooftop equipment

Air units, fans, and pipes often sit on the roof. During a new roof, many of them must be lifted so the new roof can go under them.

Plan this early. Ask who will disconnect and reconnect each unit. Ask whether the curbs, which are the raised boxes under units, will be raised or replaced. Taller curbs can make room for thicker foam boards.

This is a common place for problems later. Make sure the roofer seals each curb the right way after units go back.

Weather and scheduling

The National Weather Service says spring is the peak severe storm season in North Texas, and summers are hot. Both can affect a roof schedule.

Many glues and coatings need dry weather and certain temperatures. Ask how the roofer plans around rain. Ask what happens if a storm hits while part of the roof is open.

Good roofers watch the forecast every day and only open as much roof as they can seal before dark.

After the new roof

When the job is done, get the closeout papers. These should include the warranty, a roof map of what was built, and the upkeep rules.

Many warranties need regular checks to stay active. Put those dates on your calendar. Our maintenance program page explains what those visits usually cover.

Planning the timing

A new commercial roof often takes months to plan. You may need a moisture survey, a design, bids, permits, and a crane date before work starts.

Start early if you can. If your roof is leaking more each year, you have time to plan now, but that window will not stay open forever. A planned project lets you pick the season, line up money, and compare bids calmly.

If the roof fails suddenly, you lose that choice. Repairs may buy a few months while you plan, but they are not a long-term answer for a worn-out roof.

Telling tenants and staff

Give people inside the building plenty of notice. Share the schedule, the parts of the building affected each week, and who to contact with problems.

Let them know about noise, smells, and parking changes. A clear note before work starts heads off many complaints.

What you find and what it usually means

Common questions

How long does a new commercial roof take?

It depends on size, weather, and phasing. Ask each bidder for a schedule and how weather delays are handled.

Can we stay open during the work?

Many do. Working in sections and sealing the roof each night is key.

Is a white roof better in Dallas?

White roofs reflect more sun, which can lower roof heat. Savings depend on the building, so ask for real estimates, not promises.

Do we need a permit?

New roofs usually need permits. Check with your city, and put who pulls it in the contract.

Can we replace only part of the roof?

Sometimes. If one section is worn out and the rest is still dry and sound, a partial replacement can make sense. Ask how the new and old sections will be joined, and how that joint will be sealed and kept under watch, since tie-in spots are common places for future leaks.

What is a cricket on a roof?

A cricket is a small raised ridge built on the roof to steer water around something, like an air unit or a wall corner. It keeps water from sitting behind that object and moves it toward a drain instead.

Do we need to move out during the work?

Many do. Some rooms under the work area may need to close for a day or two, especially if the deck is being repaired. Your roofer should tell you which areas are affected and when.