torch down roof repaired with spray foam

Torch Down Roof Repair – What Options Do You Have?

Greg PalyaSpray Polyurethane Foam Roofing

So, you have a torch down roof and you’re looking into repair options. You’re also probably wondering about cost, warranties, if you need to rip everything off, etc.

In this post, you’ll learn:

  • What’s the first thing a commercial roofing contractor will do?
  • What repair options you’ll have?
  • What are the costs and warranties?
  • What you should do now?

I wanted to point out that we only write articles based on true events and experiences. West Roofing Systems has been in spray foam roofing since 1979. Every piece of content written is produced in-house. And every article is reviewed and edited by a roofer/salesman with 30+ years of experience in the field.

Let’s get started!

What’s the first thing a commercial roofing contractor will do?

The first thing they will do is collect as much information from you as possible about your roof. Questions they might ask you are:

  • How old is the roof?
  • How many roofing systems are installed?
  • Is your torch down roof 2 or 3 plies?
  • How much leaking is happening?
  • Are the seams intact?

Then the contractor will want to schedule time with you to get onto the roof. They will be looking at seam integrity, how much of the insulation is wet, and if the membrane is eligible to be restored or not.

Once all data has been collected, a contractor can give you some repair recommendations.

What repair options will you have?

If you already have two or more roofing systems installed, you will need to remove at least one system before installing another. Building code states that the maximum number of roofing systems on a commercial building is two.

If your torch down roof is in good shape, meaning:

  • The seams and membrane are intact
  • Less than 25% of the roof’s insulation is wet
  • There’s been at least annual maintenance on the roof

You can install a roof coating system over your existing torch down roof and avoid the costly complete tear-off.

This is because roof coating systems are considered “maintenance” and not another “roofing system”. The cost for a coating system used to be $2 – $4 per square foot in the Summer of 2021, but with product and labor shortages, the cost can be much higher.

What happens if you only have one roofing system installed?

If you only have one roofing system installed, then you can install any roofing system you’d like. Just make sure you identify and remove all the wet insulation first.

One roofing system that might be cost-effective for you is a spray polyurethane foam roof.

This is because foam can be installed right over the torch down roof without a coverboard, any insulation, or any added materials to create slope.

spray foam roof at Tree Services in Elyria, Ohio

If the torched-down membrane is aged and has some loss of adhesion, a contractor can put screws and plates in those needed areas, then apply foam over the roof.

This can save a torched-down roofing owner the cost of removing the entire roof and transporting the materials to a landfill.

If you are new to spray polyurethane foam roofing, here’s a blog post that explains the basics:

“Blog post – What are the basics of Spray Polyurethane Foam (SPF) Roofing?

You can also consider installing a single-ply roof, such as TPO or EPDM.

These rolled-out sheets can be installed right over your existing torched-down roof. You might need to watch out for low areas where standing water can occur.

To eliminate standing water, you might need to install a tapered, polyiso system, which can be costly and labor-intensive.

You can also consider more “torch down plies”

This probably isn’t the greatest option. One, because most torched-down roofing companies have moved onto other systems, such as spray foam, single-plies, or roof coating systems.

Two, torched-down roofing is messy and it’s a fire hazard working with an open flame.

Cost of commercial roofing systems

If we were talking about the Summer of 2021, I could tell you that the prices for roofing systems could be “ballparked” as:

  • Roof coating systems – $2 – $4 per sq. ft.
  • Spray polyurethane foam – $4 – $6 per sq. ft.
  • Single-ply – $4 – $6 per sq. ft.
  • Torch down and modified bitumen – more than all the roofing systems above

NOTE: We don’t deal with (or compete against) torch down and modified bitumen that often, and therefore don’t have an accurate price a contractor would charge.

But since it’s not 2021, the prices for all roofing systems have increased. A general contractor told us that polyiso board isn’t available till the Fall of 2022. Another told us that fasteners and adhesives aren’t available till 2023.

Prices have increased dramatically for roof coating systems and spray polyurethane foam.

In short, the commercial roofing market is very volatile. Who knows, next month everything could be back to 2021 prices.

Warranties of commercial roofing systems

Because we’ve been in the spray foam and roof coating system industries since 1979, both spray foam and coating systems have similar warranties:

  • For a 10-year warranty, 20 mils of coating need to be installed
  • For a 15-year warranty, 25 mils of coating need to be installed
  • For a 20-year warranty, 30 mils of coating need to be installed

Warranties for single-ply and torch-down roofs vary between 10 and 20 years.

Since every roofing system can come with a similar warranty, the most important things to consider are:

  • Will the contractor be in business for the length of the warranty?
  • And if they disappear, who honors the warranty going forward?

Here’s a good article that goes more into depth on warranties, what’s covered, what’s the difference between contractor and manufacturer warranties, etc.

What should you do now?

The first thing you should do is find a few roofing contractors. Have them each come to your torch down roof and submit their recommendations.

You might find that some contractors are offering different solutions (or a completely different roofing system) that other contractors aren’t.

But having multiple opinions (and getting different cost numbers) will help you in making the right choice for your situation.

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About the Author

Greg Palya

Greg Palya is the Digital Content Manager of West Roofing Systems, Inc. He has a B.S. in Marketing from the University of Akron and an MBA in Marketing from Walsh University. When he's not trying to teach others about spray foam roofing and silicone roof coatings, you can find him on the basketball court or golf course.