1. How do I maintain my single-ply roof?
  2. Are sheet membranes available in colors?
  3. How do I cover my patio deck with a sheet membrane?
  4. What wind ratings are available for sheet membranes?
  5. How do I determine the exposure category or exposure zone (wind) for a building?
  6. Can I reuse the existing insulation on the roof when I re-cover/re-roof?
  7. Do you have installation specifications for sheet membrane systems?
  8. Can you recommend a roofing contractor in my area?
  9. How long will sheet membrane roofs last?
  10. Can I adhere Modified Bitumen membrane directly to a wood deck?
  11. Does an edge system need to be a complete system to meet the requirements of ES-1, or can an ES-1 designed/tested component (such as a cleat) be added to an untested component (such as a cover) to produce an ES-1 compliant system?
  12. Does the IBC code requirement that perimeter edge metal be tested per ANSI/SPRI ES-1 mean that I must use pre-engineered metal edge products?
  13. Is ES-1 only a design standard, meaning that any organization can manufacture an ES-1 compliant edge simply by using an ES-1 design? Or is ES-1 a manufacturing standard, meaning that the organization which manufactures the edge system needs to demonstrate that the system meets ES-1 as tested by an independent agency?
  14. Do all sizes and gauges of roof edge products need to be tested or can it be assumed that smaller sizes and heavier gauges of an identical product produced by the same fabricator will provide equal or better resistance ratings?
  15. Is SPF considered to be a membrane as the term is used in 1504.5 and does an edge system used with a SPF need to be tested according to ES-1?

  1. How do I maintain my single-ply roof?

  2. Answer: All low slope roofs should be inspected at least twice per year and after any major storm. Look at the perimeters to determine if there is any loose metal or fasteners, the roof should not have loose membrane or fasteners that form tents. Pay particular attention to flashings around penetrations. Make sure they are tight and undamaged. Remove debris and ensure that all drains should be open. Note any changes from the past inspection, and if questions arise, consult the contractor that installed the roof or a Registered Roof Consultant.

    For more information on roofing maintenance you can purchase the SPRI/NRCA document Manual of Roof Inspection, Maintenance, and Emergency Repair for Existing Single Ply Roofing Systems from the National Roofing Contractors Association at www.nrca.net.

  3. Are sheet membranes available in colors?

  4. Answer: Sheet membranes come in black and white and a large variety of standard or custom colors on request. You can find more detail on availability of colors by going to www.spri.org, clicking on "Our Members" and then clicking on a Member's web site.

  5. How do I cover my patio deck with a sheet membrane?

  6. Answer: Most SPRI Members provide a variety of materials utilized for and in waterproof deck systems. You can get more information by going to www.spri.org, clicking on "Our Members" and following the links to the members of SPRI that supply membranes.

  7. What wind ratings are available for sheet membranes?

  8. Answer: Sheet membranes are rated in pounds per square foot of uplift resistance. Factory Mutual is one of the more widely recognized agencies that measure uplift pressure. Factory Mutual uplift pressures are reported from 60 pounds per square foot to 999 pounds per square foot uplift resistance (FM 1-60 to FM 1-999). You can get more detail on a specific products uplift resistance s by going to www.spri.org, clicking on "Our Members" and then click on a member's web site.

  9. How do I determine the exposure category or exposure zone (wind) for a building?

  10. Answer: Exposure categories or wind zones are described in the SPRI publication Wind Load Design Guide for Low Sloped Flexible Membrane Systems under G Building Location. This document is available for purchase from SPRI. A publication form is available at www.spri.org. The more detailed exposure category information is available from ASCE 7-98 which is produced by The American Society of Civil Engineers, 1801 Alexander Bell Drive, Reston VA 20191-4400. The information is also available in the International Building Codes and many other Code documents.

    "Simple" descriptions have been prepared for exposure categories as follows are:

    1. Large city centers with at least 50% of the buildings having a height in excess of 70 ft.
    2. Urban and Suburban areas, wooded areas, or other terrain with closely spaced obstructions having the size of single-family dwellings or larger.
    3. Open terrain with scattered obstructions having a height generally less than 30 ft.
    4. Flat unobstructed areas such as the shore of a lake or ocean in a non-hurricane prone area.


  11. Can I reuse the existing insulation on the roof when I re-cover/re-roof?

  12. Answer: The re-use or re-cover of building products, including insulation, is typically an economic choice. Recent technology advances and product developments will not be present in previously installed products. The owner/owner's representative must compare these product "enhancements" to the economic advantages of re-using or re-covering the existing products. Individual manufacturers should be consulted regarding specific criteria for re-use and re-cover of existing building products.

    Insulation looses very little R-value after the first five years; therefore, older dry insulation is likely to maintain a significant portion of its original R-value. SPRI research has shown that damp insulation can dry to the interior of buildings if there are no barriers between the insulation and the building. (Typically, wet roofs on metal decks with no vapor barrier will dry, whereas insulation over concrete decks has no opportunity to dry to the interior.) Before re-covering over existing insulation, it is advisable to make core cuts to determine the characteristics of the existing system, primarily to determine if there is a vapor barrier in the system that would prevent drying. It is advisable to conduct moisture surveys to determine if wet insulation exists and where it is located. Most roofs will not be entirely wet. The wet insulation can be removed from areas where the system will not be able to dry, and be replaced with new insulation. Again, consult the individual manufacturer regarding specific criteria for reuse and re-cover of existing building products.

  13. Do you have installation specifications for sheet membrane systems?

  14. Answer: SPRI offers generic guide specifications for installation of membranes on its CD-ROM, Flexible Membrane Roofing: A Professionals Guide to Specifications, which can be purchased from SPRI. A publication order form is available on our web site www.spri.org. Many of the SPRI membrane manufacturer members also have guide specifications for their products available on-line. You can connect with the manufacturers at www.spri.org and going to "Our Members" section. Click on the links to the manufacturers.

  15. Can you recommend a roofing contractor in my area?

  16. Answer: There are several ways to find a contractor in your area. The first is the yellow pages of your telephone directory. You can check out the contractor with the Better Business Bureau. Many manufacturers have lists of contractors by area of the country. You can find the SPRI Member manufacturers lists by going to www.spri.org, clicking on "Our Members" and following the links to their web sites. You can also contact the National Roofing Contractors Association at www.nrca.net. Clicking on "Find a Contractor" will provide a list of contractors in your area that participate in the national organization.

  17. How long will sheet membrane roofs last?

  18. Answer: Due to the variety of conditions and circumstances that exist, no guarantee of length of life of any roofing product can be made. However, SPRI has represented successful sheet membrane manufacturer's for over 20 years. Quality roof membranes, properly installed and maintained are still performing today.

  19. Can I adhere Modified Bitumen membrane directly to a wood deck?

  20. Answer: Most suppliers of Modified Bitumen sheet membrane recommend the use of a mechanically attached base sheet over a wood deck. Consult the membrane supplier by going to www.spri.org and clicking on "Our Members" and following the links to the individual suppliers of modified bitumen membranes.

  21. Does an edge system need to be a complete system to meet the requirements of ES-1, or can an ES-1 designed/tested component (such as a cleat) be added to an untested component (such as a cover) to produce an ES-1 compliant system?

  22. Answer: ES-1 requires that fascia and copings be tested to RE-2 and RE-3 respectively. In both tests the load is applied to the metal that provides the surface to the wind. Therefore, these systems need to be tested as a complete assembly.

  23. Does the IBC code requirement that perimeter edge metal be tested per ANSI/SPRI ES-1 mean that I must use pre-engineered metal edge products?

  24. Answer: The NRCA has had some specific coping and fascia products ES-1 tested, and NRCA members that are sub-listed with the NRCA can fabricate those ES-1 tested products. However, simply copying the NRCA products does not mean you have produced an ES-1 tested product. The sub-listed contractors are provided detailed fabrication information and they are audited by the NRCA’s testing agency to assure that the products they produce are equal to those that have been tested.

  25. Is ES-1 only a design standard, meaning that any organization can manufacture an ES-1 compliant edge simply by using an ES-1 design? Or is ES-1 a manufacturing standard, meaning that the organization which manufactures the edge system needs to demonstrate that the system meets ES-1 as tested by an independent agency?

  26. Answer: Section 6.0 of the ES-1 standard states, "Edge details may be selected from manufacturers who certify certain minimum performance to meet design requirements, based upon testing. Other designs may be used, provided they are tested and certified by an independent testing laboratory to meet the wind and pullout resistance design standards in the ES-1 definition." It is the opinion of SPRI that a critical element in meeting a design standard is a fabricator's manufacturing capabilities. Therefore, ANSI/SPRI ES-1 testing should be performed on systems as manufactured by a given fabricator.

  27. Do all sizes and gauges of roof edge products need to be tested or can it be assumed that smaller sizes and heavier gauges of an identical product produced by the same fabricator will provide equal or better resistance ratings?

  28. Answer: All sizes and gauges do not need to be tested. The generally accepted position of those doing ES-1 testing is that a product has an equal resistance to that of a tested product if it is (all 5 must be met):
    • the same design and configuration
    • produced by the same fabricator
    • manufactured from the same material
    • an equal or heavier gauge
    • an equal or smaller size


  29. Is SPF considered to be a membrane as the term is used in 1504.5 and does an edge system used with a SPF need to be tested according to ES-1?

  30. Answer: It is SPRI’s opinion that because SPF is not a ballasted or mechanically attached system there is no need for a RE-1 test to be performed on edges used with SPF. However tests RE-2 and RE-3 are to determine the edge metal’s resistance to the calculated wind load regardless of the roof system. Therefore it is SPRI’s opinion that in order to meet ES-1 all perimeter edge metal for low slope roofs need to be tested according to either RE-2 or RE-3.




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