So, you have a flat roof that’s leaking. What repair options do you have?
You could:
- Remove and install the same roofing system you already have
- Add coating over an existing roof
- Install spray polyurethane foam over your existing roof
The existing condition of your roof determines the best repair option. Roof is in good shape (not a lot of saturated insulation), then you likely can install something over top, such as spray foam or a coating system.
Roof in bad shape…you might have to tear it all off and start over.
Learn more about this below:
But first, we recommend getting a roofing contractor onto the roof.
Why?
Because once the current conditions of the roof are determined, then you’ll know the best repair option.
For one, maybe the roof isn’t in bad shape. Therefore, you can do a simple repair over a small area, and you’re done.
Or, maybe your flat roof has a small leak, but over 50% of the insulation is wet. In this case, tearing the roof off might be in your best interest.
If you’re somewhere in the middle, perhaps re-roofing is the most cost-effective roof repair option.
At West Roofing Systems, we’ve been inspecting all kinds of commercial roofs since 1979. We specialize in spray foam roofing and roof restoration with coating, but we’ll always give you the most cost-effective option based on the current conditions of your roof.
Let’s get into the three options you’ll have for re-roofing a flat roof.
Re-roofing option #1 – Install the same roofing system
If you have a single-ply, metal, built-up, or any commercial roofing system, you can always remove what you have and install the same system.
Maybe you’re a fan of single-ply roofing systems, so you’re going to stick with that.
Perhaps there have been improvements in single-plys since your last installation?
No matter which roof system you currently have, you can always remove it and install a new one.
NOTE: In some cases, completely removing a roof system on your flat roof is NOT a cost-effective way to make it watertight. Read more about cost-effective options below.
Re-roofing option #2 – restore your roof with an elastomeric coating
Let’s say you did have that single-ply roof with a few leaks.
After an inspection, it’s determined that 15% of the roof’s insulation is saturated.
A cost-effective option that some building owners don’t know about is a roof coating restoration.
This is done by installing high-quality, waterproof silicone over an existing roof.
How is this done? Checkout the video below:
To restore a roof (let’s say it’s an EPDM rubber roof), a roofing contractor would identify the wet insulation and remove only those areas.
They will replace the wet insulation with new, dry insulation and EPDM.
Now, they will prepare the existing roof by power washing it clean. They will also perform adhesion tests to ensure the coating adheres correctly.
Next, they will treat the seams (since these areas are prone to leaking).
Then, they will apply a certain coating thickness to the entire roof. A thicker application grants a longer warranty. For example:
- A 20-mil total thickness grants a 10-year-warranty
- A 25-mil total thickness grants a 15-year-warranty
- A 30-mil total thickness grants a 20-year-warranty
NOTE: A roof restoration saves money versus a complete replacement/tear-off because the contractor only removes the wet areas of the roof.
Re-roofing option #3 – Install a spray foam roofing system
If your flat roof is leaking, it could be due to several things, such as:
- There isn’t a proper slope to transport water to drains
- There are holes in the membrane
- Flashings around penetrations aren’t watertight
If any of these things are happening to your flat roof, an option to consider is a spray foam roof.
Why?
Because spray foam can eliminate all three of the issues above.
How so?
Spray foam can influence proper slope
With spray foam being fluid-applied, a contractor can add as much slope as needed in certain areas of the roof.
Some areas might be raised 1 inch, some only ½ of an inch.
Some areas with ponding or standing water might be 10 feet by 10 feet, and others might be 2 feet by 2 feet.
Regardless, because spray foam is spray-applied, a certified installer can customize the slope of an entire roofing system so that water is always headed toward the drains.
Spray foam fills in holes in the membrane
Did you know that spray foam expands 30x its size within a few seconds?
Because spray foam creates a monolithic (one-layer) roofing system, it can fill all the existing holes in a roof membrane.
Here’s a short video of spray foam being installed. Notice how there are no seams and no fasteners. Every microscopic opening is covered:
Spray foam can make flashings watertight again
Over time, flashings break down, lose adhesion, or become cracked, giving water an entry point into the insulation.
With foam being spray-applied, a contractor can spray over the top of the existing flashings and make it a part of the one-layer roofing system.
What are you supposed to do with your flat roof now?
The first step is to contact a roofing contractor. They will set up an appointment with you to walk the roof and perform a roof inspection.
Once they complete the inspection, they will give you possible solutions based on what they found on the roof.
You can then begin to weigh the pros and cons of each option and decide.
Want to learn more?
Please see the free downloadable guides below:
