Frequently Asked Questions – RoofKit EPDM

Below are a number of frequently asked questions (FAQs) regarding the installation and repair of RoofKit EPDM rubber roofing membrane.  We also encourage you to review both the Pocket Application Guide and Instructional Video for additional information.

Frequently asked questions for RoofKit White Reinforced Membrane will be available soon.  Please check back, or contact customer support at 1-800-225-4714, Ext. 7888

1. Can I use RoofKit EPDM membrane as a pond liner?
No, the RoofKit membrane is a roofing grade material. Use only certified fish- friendly membrane available by special order.

2. What are the sizes, thicknesses and roll weights of RoofKit EPDM membrane?

10’ x 20’
15’ x 25’
10’ x 50’
10’ x 100'
20’ x 50’
20’ x 100’
10’ x 50’  
10’ x 100’
20’ x 50’
20’ x 100’
.045 mils 
.045 mils 
.045 mils 
.045 mils 
.045 mils 
.045 mils 
.060 mils
.060 mils
.060 mils
.060 mils
60 lbs.
113 lbs.
155 lbs.
310 lbs.
310 lbs.
620 lbs.
200 lbs.
400 lbs.
400 lbs.
800 lbs.

3. Is RoofKit EPDM membrane available in different colors?
The membrane is available only in black, because this color provides the most UV resistance and the best long-term performance.

4. What slope is acceptable for application of RoofKit EPDM membrane?
Any slope is fine, but a slope exceeding a 2” in 12” pitch requires using our RoofKit Contact Adhesive or Multi-Purpose Adhesive.

5. Does RoofKit EPDM membrane break down under direct sunlight (UV light)?
No. It has excellent UV resistance and will provide many
years of service with no ill effects.

6. Can I put indoor/outdoor carpeting over the EPDM membrane?
Yes, you can adhere it using either the Multi-Purpose or Contact Adhesive. The only exception would be rubberbacked carpets which may lose adhesion over time.

7. Are any RoofKit products harmful or hazardous?
Safety Data Sheets are available for all RoofKit products.

8. Will the RoofKit EPDM membrane be damaged by asphalt-based products?
Yes. The membrane should not come in contact with roof cement, black jack, or other asphalt-based products.

9. What does the RoofKit warranty cover?
StaFast Roofing Systems warrants to you, the purchaser of its cured RoofKit EPDM membrane (“Product”), and to subsequent owners of the premises on which the Product is installed, that the Product is free from manufacturing defects and will not prematurely deteriorate due to weathering.

10. How long will the RoofKit EPDM membrane last?
Because this is the same quality material as our commercial grade membrane, under normal circumstances the RoofKit EPDM membrane has a limited ten-year warranty.

11. How hot does the RoofKit EPDM membrane get in the summer?
The membrane can get very hot in direct sunlight, but it is able to provide watertight integrity over a wide variety of temperatures.



12. What roof insulation board should I use as an underlayment for the membrane?
Use a commercial grade roof insulation board, OSB board, or plywood.

13. What do I do if I have a metal roof deck?
A minimum of one-inch roof insulation board must be installed directly over the metal deck. Then secure the insulation to the deck with RoofKit screws and plates, using 10 screws and plates per 4’ x 8’ board.

14. Can I install RoofKit EPDM membrane directly over felt paper?
No. A new commercial grade roof insulation board, OSB board, or plywood is recommended.

15. Can I install RoofKit EPDM membrane directly over an existing roof?
Yes, but a new commercial grade roof Insulation board, OSB board, or plywood is required.

16. How do I fasten the roof insulation board?
Use RoofKit plates and screws, installing a minimum of 10 plates per 4’ x 8’ board. (See Application Guide.)

17. Can I apply RoofKit EPDM membrane directly to a plywood surface?
Yes, making sure that the surface is clean, dry, even, with no sharp corners.

18. Can I install roof insulation board over an installed EPDM membrane system?
No, this is not recommended.


19. What adhesives can I use to adhere the membrane to the roof surface?

RoofKit Latex Bonding Adhesive, Contact Adhesive, or Multi-Purpose Adhesive.

20. What adhesive must be used for membrane-to-membrane applications?
Use only the RoofKit Multi-Purpose Adhesive.

21. How do I use the RoofKit Latex Bonding Adhesive?
Apply Latex Bonding Adhesive to the substrate using a large, thick-nap paint roller. Spread a sufficient layers of adhesive so the roof surface is completely covered. Roll the EPDM membrane into the wet adhesive. Then, using a stiff-bristled push broom, apply sweeping pressure to ensure a smooth application of the membrane. Do not use Latex Bonding Adhesive on metal surfaces.

22. At what temperature can I apply the RoofKit Latex Bonding Adhesive?
The temperature must be above 40 degrees F.

23. What happens if the RoofKit Latex Bonding Adhesive freezes?
This could damage the adhesive and affect its performance.

24. How do I use the RoofKit Multi-Purpose Bonding Adhesive?
The Multi-Purpose Bonding Adhesive can be used for any application on the roof: adhering the membrane to a substrate or membrane-to-membrane seaming. This adhesive must be applied to both the membrane and the substrate in a thin coat using a small-nap paint roller. Allow the adhesive to dry (tacky), then bring the membrane and substrate together in a contact fashion. All membrane-to-membrane applications require the cleaning of both surfaces with RoofKit Seam Primer, using a scrub pad.

Apply the adhesive to both surfaces with a 3” paintbrush. Allow the adhesive to dry, then bring both membranes together.

25. How do I use the RoofKit Contact Adhesive?
RoofKit Contact Adhesive is used to adhere EPDM membrane to a substrate using a small-nap paint roller. Apply the adhesive to both the membrane and the substrate, allow to dry tacky to the touch, then bring together the membrane and the substrate in a contact fashion.

26. How long does it take for the adhesive to set up or dry to a tacky touch?
For RoofKit Multi-Purpose and Contact Adhesives, drying time is usually 15 to 30 minutes depending on temperature and humidity. For RoofKit Latex Adhesive, the membrane must be installed while the adhesive is still wet.

27. How do I adhere RoofKit EPDM membrane to a wall?
Apply RoofKit Multi-Purpose or Contact Adhesive on the wall and the membrane using a small-nap paint roller. Allow the adhesive to dry to a tacky touch. Then place the membrane on the wall in a contact fashion. Do not use RoofKit Latex Bonding Adhesive on any vertical surface.

28. What are the container sizes and coverage rates for the RoofKit adhesives?
Latex Bonding Adhesive: 1 gallon and 3.5 gallons, 100 sq. ft. per gallon.
Multi-Purpose Bonding Adhesive: 1 gallon, 60 sq. ft. per gallon
Contact Adhesive: 5 gallons, 60 sq. ft. per gallon

29. Can I use wood glue to install RoofKit EPDM membrane?
No, use only RoofKit adhesives to ensure a quality installation.


30. How do I best complete the seaming of RoofKit EPDM membrane?
Detailed instructions are available on the carton of the RoofKit Seam Kit.

31. What are the differences between RoofKit tape products? How are each used?
RoofKit Seam Tape (3” x 50’) is used as the adhesive for the overlap of two pieces of membrane that are to be seamed together. (See Application Guide.) RoofKit Tape Flashing (12” x 25’) is used to seal corners at skylights, chimneys, or at the junction of walls, and to protect any irregular surface. RoofKit Seam Primer and a scrub pad must be used to clean all membrane surfaces before using the Tape Flashing.

RoofKit Cover Strip (5” x 50’) covers the RoofKit Fastening Termination Bar or the flange of the edge metal detail on a flat roof surface. RoofKit Seam Primer and a scrub pad must be used to clean the edge metal flange and 4” of the adjacent membrane before using the Cover Strip. (See Application Guide.)


32. What installation aids are available to help me install RoofKit EPDM membrane?
Both a printed installation guide and an instructional video are available to assist you.

33. How many people are needed to install a RoofKit EPDM system?
This would depend on the size of the project, but for many reasons it is recommended to have at least two people.

34. How is the RoofKit Fastening Termination Bar used?
The Fastening Termination Bar is used for the attachment of the membrane at wall and edge details. It is attached with RoofKit screws (or masonry fasteners, if required).

35. What do I use to seal the perimeter of my roof?
Use either the RoofKit Fastening Termination Bar or a prefabricated edge metal. (Refer to the Application Guide.)

36. How do I install the edge metal detail at the perimeter of my roof?
After the membrane has been rolled over the edge a minimum of 2”, install the edge metal using RoofKit screws, securing the flange to the roof deck every 4”to 6”. Use RoofKit Seam Primer and a scrub pad to clean the edge metal and 4” of the adjacent membrane, then cover with RoofKit Cover Strip. Assure good contact by rolling with a seam roller. Suggested edge metal: 155-1134, 155-1105.

37. Where do I use the RoofKit Rubber Caulk?
Caulk is used for sealing the edge of a membrane seam, at the edges of flashing details and patches, and at the top edge of Fastening Termination Bar details.

38. What should I do about a pipe vent on my roof?
Use the RoofKit Rubber Pipe Boot with Steel Clamp. Use Seam Primer and a scrub pad to clean the membrane surface around the pipe a minimum of 4” larger than the Pipe Boot. Place the Boot over the pipe and cut to the correct size (1” to 6”). Position the Boot onto the roof surface and remove the release paper. Secure the Boot with a seam roller, clamp the top of the Boot with the steel clamp, and seal all edges with RoofKit Rubber Caulk.

39. How do I repair a tear or rip in the RoofKit EPDM membrane?
Cut a patch out of RoofKit Cover Strip to extend 3” past the tear, making sure to round all corners on the patch. Clean the torn area with RoofKit Seam Primer and ascrub pad about 2” wider than the size of the patch. Wait for the Primer to dry, then pull off the release paperon the Cover Strip and place the patch over the primedarea. Assure good contact by rolling with a seam roller,then apply RoofKit Rubber Caulk around the edge ofthe patch.

40. Can I walk on the RoofKit EPDM membrane after I install it?
Yes, but be careful not to rip or puncture the membrane with sharp objects.

41. What should I do if a wrinkle gets in the membrane during installation?
Although a wrinkle is not very attractive, it will not affect the performance of the roof. There is one exception: if it is within 3” of a seam, it must be cut out and patched with Cover Strip or a piece of membrane.

42. How do I patch a hole larger than the 5” RoofKit Cover Strip?
Cut a patch out of an extra piece of EPDM membrane larger than the hole, and round the edges of the patch. With Seam Primer and a scrub pad, clean the mating surface of the patch and the installed membrane a minimum of 4” larger than the hole. Apply RoofKit Multi-Purpose Adhesive to the patch and the area surrounding the hole with a small-nap paint roller. After drying to a tacky touch, place the patch over the hole, roll the edge of the patch with a seam roller, and seal the edges with RoofKit Rubber Caulk.

43. What maintenance is required for my new RoofKit EPDM membrane system?
Inspect your roof twice a year to keep all gutters, drains and the roof surface free of debris.