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How to repair a rubber roof – in Philadelphia.

The area that causes the leak must be identified. There are several videos on this page that will help you just do that.

In this video, I point out possible issues to look for on flashing against a chimney or brick wall.

Step 1:  Determine the type of flat roof you have.

There are basically three types of rubber membranes found on flat roofs:

  1. EPDM Rubber Membrane – This is the most common rubber membrane found on flat roofs. You can tell it buy the look and feel of it. It is smooth and looks like the rubber of an inner tube of a tire.
  2. TPO Vinyl Membrane – Stands for Thermoplastic polyolefin (TPO) single-ply roofing membrane. This is a white plastic or PVC type of roofing membrane
  3. Modified Bitumen Torch Down Rubber Membrane – This type of rubber membrane comes only in three feet wide rolls. When you see seams every three feet, then it is most likely a Modified Bitumen Torch Down Rubber Roof.
flat roof repair on EPDM, TPO Vinyl and MB Torch Down rubber roofs {zipcodes}

EPDM Rubber      TPO Vinyl Roof       Torch Down Rubber Roof

Step 2: Identify how old the roof is

An invoice or receipt will help or call the roofing contractor that did the installation. You can rough guestimate the age as well.

Advice from Flat Roof Doctor:

If the following conditions are met, then it becomes questionable to make extensive repairs on:

Life Expectancy of different Roof Membranes

  • Torch Down Rubber Roof  –  Life expectancy changes drastically if it goes unprotected
  • EPDM Rubber and TPO Vinyl Roof does not come with ultraviolet protection

Ultraviolet Rays cause roofs to fail. Depending on which part of the country and how much the roof was exposed to the sun, how long Roof Membranes will last.

Step 3: Identify where the area is that causes the problem to make the necessary Rubber Membrane Repairs.

Each Roofing System has there own issues that could cause leaks. Once you know what Roofing System you have and how old it is, then proceed to the section that applies.

Gucci Roofing
72 reviews
10212 Woburn Pl, Philadelphia, PA 19114

Reiter Roofing
26 reviews
759 S 5th St, Philadelphia, PA 19147

Loonstyn Roofing
18 reviews
2048 Fairmount Ave, Philadelphia, PA 19130

Castelli Roofing and General Contractors
15 reviews
2523 S 21st St, Philadelphia, PA 19145

How to repair an EPDM Rubber

These 3D animated videos show you where to look for leaks on an EPDM Rubber

Seams on an EPDM Rubber

The likeliest place for an EPDM Rubber to leak is at the seams. The number one reason for EPDM Rubber Roofs to start leaking is due to Adhesive failure that bonds the seams together and or where the rubber is attached to metal.

  • If you pull up on an overlapping seam, and the two surfaces separate easily, then you know the adhesives has failed. You should not be able to pull a seam apart with considerable force.
  • Look for voids under the membrane – this happens when the rubber shrinks over time and pulls away from the edging or flashing. This will cause stress on the seams and cause it to fail.
  • look for seam failure around skylights, air conditioner cubs, and vents

My Advice:

If you are a homeowner and there are only a few seams on the roof with a few skylights, then repairing the roof with seam tape is advisable. There is a list of tools and materials below that you can follow to make the necessary repairs.

If you have a commercial roof that’s over 3000 sq ft, then you should be careful spending the money repairing it. Normally a repair can start at 20% of the replacement cost of the roof and will escalate from there in the next few years. When EPDM seams start to fail, that means the roof was exposed to harmful ultraviolet and not only did the adhesive failed, but the rubber is getting brittle and is starting to shrink.

Never, but never ever install EPDM Rubber on a commercial roof – it is a waste of money

The first method of making flat roof repairs on an EPDM Rubber

  • Clean the area, seam from all debris with a rag and lacquer thinners
  • Remove old lap sealer (caulking)  from the seams
  • Apply a fresh beat of lap sealer (butyl caulking) not silicone, at the seams.
  • Smear the beat of butyl caulk with your finger to make sure the seam is properly covered.

The Second method of Making Flat Roof repairs on an EPDM Rubber

  • Buy a roll of cover tape and a gallon of primer at a roofing supply
  • Clean the surface thoroughly with a rag and lacquer thinners
  • Remove old caulking from the seams – this is important because the caulking cause a bump
  • Apply the primer an wait till touch dry
  • Cut the correct length of cover tape, peel the paper back off and apply it to the surface where the primer was applied
  • Take an edge hand roller, and roll over the cover tape with enough pressure to make it stick. Make sure all the trapped air bubbles are rolled out
  • When some air pockets persist, take the sharp point of the utility knife, and pop these bubbles by making a small insition hole into the cover tape where the bubble is

Below are the Tools and Materials needed to make an EPDM Rubber

Lacquer Thinners, Rags and gloves

Lacquer Thinners, Rags, Gloves for repairing an EPDM Rubber Roof
Hand Roller to be used on EPDM Rubber Roof repair seams

The EPDM Rubber Seam roller

This is an important tool. Once the EPDM Cover tape is placed over the adhesive or primer, then this roller is used to roll the cover tape tight into the rubber membrane as to make a tight seal

EPDM Lap Sealer or Butyl Caulking

Flat Roof Repair - EPDM Lap Sealer or Butyl Caulking
Flat Roof repair - Professional Caulking Gun to be used on an EPDM Rubber Membrane

Professional Caulking Gun

EPDM Cover Tape Roll

Flat Roof repair - EPDM cover Tape to be used on an EPDM Rubber roof
Paint Brush to brush on the primer before placing the cover tape

Disposable Paint Brush to apply the primer

Milwaukee Utility Knife  – for slicing the cover tape

Milwaukee Utility Knife to slice EPDM Rubber cover tape

Important notice:

When using the EPDM Rubber primer, make sure you follow the instructions on the can. The contact cement has to be applied a certain way and there should enough time pass by from the time the primer was applied with a brush, to the time when the cover tape gets placed.

Flat Roof Repair - Primer for EPDM Rubber membranes to be used on seam tapes

EPDM Cover Tape Primer

How to repair a Torch Down Rubber Roof

Watch the video and towards the middle, you will notice that the technique in the video above was applied to the roof we did 6 years ago

Life expectancy For a Single Ply Torch Down Rubber Roof that was protected with Aluminum Coating or ceramic coating

Torch Down Rubber Roof

If you have a Torch Down Rubber roof and it was protected against ultraviolet rays with a silver coating or a ceramic surface, then it could last indefinitely. These roofs are tough and as long as there is a protection on it, they will not go bad.

If it was not protected, then you have to look for certain signs to determine if it’s repairable or not.

  1. Spider cracks in the surface – the entire surface will have these fine cracks, but it could be just in the beginning stages and you could still repair the roof
  2. Look for seam separation – if the installer didn’t know how to use a torch properly to fuse the seams together, then the repair will be costly.
  3. Look for shrinkage. If there is evidence that the rubber membrane is pulling away from the wall or flashing due to its age, then it could still be repaired but at a considerable cost.
  4. Deep spider cracks mean the roof is over 10 years old. This could mean that it was not protected and it becomes too costly to repair.

Spider Cracks in the surface of an unprotected Torch Down Rubber Roof. If you see cracks like these then the roof is approximately 10 to 12 years old

Spider Cracks on a Torch Down Roof - Repairing a Flat Roof

Torch Down Rubber Roof

There are many types of Modified Bitumen Rubber. From a Torch Down to a peel and Stick type

To make repairs on a Torch Down Rubber Roof is not always easy. It all depends on how well the seams were welded, and what type of protection did the membrane have over the years.

Don’ts for flat roof repair on a Torch Down Rubber Roof

  • Do not use silicone caulking
  • Do not use roofing cement or tar from Home Depot or a Hardware store
  • Do not paint the roof with Silver Coating in the hope that it will seal the leaky area
  • Do not smear tar all over every seam and likely place you thought it could leak from

I guarantee you that if you apply the above-mentioned methods for a flat roof repair on a Torch Down Rubber Roof, you very likely will have to do a new roof.

There are several ways on how to repair a Torch Down Rubber Roof

Flat Roof repair list of things to know before deciding what to do

  • Step 1 – Determine how old the roof is
  • Step 2 – How much the repairs will cost
  • Step 3 – What is the current life expectancy of the roof
  • Step 4 – What type of roofing membrane is on the roof
  • Step 5 – How much a replacement will cost
  • Step 6 – How many repairs are already there

Follow this list to make better decisions whether you should repair or replace the flat roof.

Method 1  – Karnak 81 Trowel Grade Adhesives

This is a Tar that comes in 5-gallon buckets that were specially designed for the Torch Down Rubber Roof materials. This tar can be used almost everywhere to make minor repairs. If a small puncture or seam separation is found, then this is the only Tar that will do the job.

How to use this Karak 81 Trowel Grade Tar

  • Clean the area from debris and moist by using lacquer thinners and a rag
  • Use a round nose trowel and scoop some of the tar and smear it over a small tear or visible opening that causes a leak
  • If the rubber membrane detached from a drip edge or metal flashing, then pull the membrane slightly back and smear The Karnak 81  covering all the metal surface about a 1/8″ inch thick. Then press the membrane back on the drip edge or flashing sticking it with tar.
  • If there is seam separation, then pull as much of the seam open and smear the Karnak 81 liberally into the seam. Then press the two materials together again to bond together

Method 2 – Using a Torch to make the necessary repairs

If the seams were not welded correctly, then it might be necessary to reweld them with a propane torch.

How to use a propane torch to weld the seams to make the necessary repairs

  • Clean the area with all  debris and make sure it is dry
  • Try to separate the seams that were not welded correctly by pulling back on the membrane. This could be a little tough to do.
  • Then with a glove and round nose trowel in one hand and a propane torch in the other, weld the seams again together
  • After running the torch the entire length of the seam, go back on top of the seam and apply pressure with the trowel to make sure the seams weld is tight. Watch the video that I have made to show how to make a seam weld.

Below are the Tools and Materials needed to make Roof Repairs on a Torch Down Rubber Roof

Round Nose Trowel

Round Nose Trowel to be used with Karnak 81 Trowel Grade Roofing cement to repair a flat roof
Modified Bitumen Torch Down Rubber Membrane for flat roof repairs

Modified Bitumen Torch Down Granular Rubber Membrane

Milwaukee Utility knife with hook blades

Milwaukee Utility Knife with hook blade for cutting the rubber membrane
Propane Tank and gloves to make a repair on a Torch Down Rubber Membrane

Propane Gas Tank and Gloves 

Propane Torch

Propane Torch to be used making repairs on a Torch Down Rubber Membrane
For repairing a Flat Roof - Karnak 81 Trowel Grade is the only Modified Bitumen Adhesive to use

Karnak 81 Trowel Grade Modified Bitumen Adhesive

How to repair a TPO Vinyl Roof

TPO Vinyl Roof

If you have a TPO Vinyl Roof, then, for the most part, it can be repaired. Depending on how much sun exposure the roof had, these roofs can last up to 20 years.

The seams are fused together and will not come apart as in an EPDM Rubber. Wipe your hand on the surface of the TPO Vinyl Roof and if your hand has white chalk on it, then it is too old to be repaired. The chalking means that ultraviolet rays have beaten too much on it and repairs will be just money down the drain.

Life expectancy For TPO Vinyl Roof

Below are the Tools and Materials needed to make Roof Repairs on a TPO Vinyl Roof

TPO Vinyl Roof membrane
  • Before making repairs, make sure the surface is clean – normally a rag and lacquer thinners will do the job
  • Buy a roof pick so you can check the seams to find any gaps
  • Buy a roll of seam tape and primer. The seam tape is unbelievable good. Follow the instructions on the can of primer
  • If you have to apply some caulking, only use urethane caulk and never silicone
TPO Cover Tape to make flat roof repairs

TPO Roll of seam Tape to make roof repairs

Scissors for TPO cover Tape roofing repair

Scissors for TPO Cover Tape Roofing Repair

Milwaukee Utility Knife to slice EPDM Rubber cover tape

Milwaukee utility Knife to be used for making TPO Roofing Repairs

Lacquer Thinners, Rags and gloves

Lacquer Thinners, Rags, Gloves for repairing an EPDM Rubber Roof

A special Heat Gun to fuse the seams together

Hand pick to probe the seam edges to find a lose seam and a roller to pressure seams together when fusing with a heat gun

Nylon Roller with a seam pick to probe seams for flat roof repairs


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Gucci Roofing
72 reviews
10212 Woburn Pl, Philadelphia, PA 19114

Reiter Roofing
26 reviews
759 S 5th St, Philadelphia, PA 19147

Loonstyn Roofing
18 reviews
2048 Fairmount Ave, Philadelphia, PA 19130

Interesting facts about Philadelphia. This is a page out of Wikipedia


Philadelphia (/ˌfɪləˈdɛlfiə/) is the largest city in the Commonwealth of Pennsylvania and the sixth-most populous city in the United States, with an estimated population of 1,567,872[7] and more than 6 million in the seventh-largest metropolitan statistical area, as of 2016[update].[5] Philadelphia is the economic and cultural anchor of the Delaware Valley, located along the lower Delaware and Schuylkill Rivers, within both the Mid-Atlantic region and the Northeast megalopolis. The Delaware Valley’s population of 7.2 million ranks it as the eighth-largest combined statistical area in the United States.[6]

William Penn, an English Quaker, founded the city in 1682 to serve as capital of the Pennsylvania Colony.[10] Philadelphia played an instrumental role in the American Revolution as a meeting place for the Founding Fathers of the United States, who signed the Declaration of Independence in 1776 at the Second Continental Congress, and the Constitution at the Philadelphia Convention of 1787. Several other key events occurred in Philadelphia during the Revolutionary War including the First Continental Congress, the preservation of the Liberty Bell, the Battle of Germantown, and the Siege of Fort Mifflin. Philadelphia was one of the nation’s capitals during the revolution, and served as temporary U.S. capital while Washington, D.C., was under construction. In the 19th century, Philadelphia became a major industrial center and a railroad hub. The city grew from an influx of European immigrants, most of whom came from Ireland, Italy and Germany—the three largest reported ancestry groups in the city as of 2015[update].[11] In the early 20th century, Philadelphia became a prime destination for African Americans during the Great Migration after the Civil War,[12] as well as Puerto Ricans.[13] The city’s population doubled from one million to two million people between 1890 and 1950.