Siplast SBS Membrane Installation Guidelines

Notice to the Reader: The instructions provided below are reprinted from the manufacturer's own materials which were submitted to the RoofStar Guarantee Program for inclusion in this Manual. The reader is urged to check these against current publications issued by the manufacturer, to ensure accuracy.

Manufacturer: SIPLAST / ICOPAL

Contact Address: See Membership List in Section 1.

Product Group: SBS MODIFIED BITUMINOUS MEMBRANES

Country of Origin: France

Country of Manufacture: France, USA, Germany, England, Poland, Denmark

Years First Installed:

B.C.: 1978
Canada: 1978
Foreign: 1967

DESCRIPTION

Siplast developed prefabricated sheet membranes in 1955 and introduced SBS Modified Bitumens in 1967, producing an elastomeric blend with exceptional elongation recovery characteristics. Reinforcing mats (consisting of polyester, fibreglass, or a combination thereof) are saturated and coated with varied thicknesses of elastomeric bitumen to produce roof membranes with specific physical properties.

Presently, Siplast manufacturers a wide variety of membranes, each designed to satisfy the demands of particular roof conditions. The “Paradiene”, “Parafor”, “Veral” and “Teranap” series are Siplast’s major membrane systems, with a number of speciality membranes designed to extend their range of applications. These membranes are available with ceramic granules, slate flakes, metal foil, polypropylene film, or sanded finishes and may be designed to be installed with hot asphalt, heat welding, adhesive or peel and stick self-adhesive in every type of roofing system.

PART 1 - GENERAL
The roofing assembly / material information published by the RCABC Roofing Practices Manual does NOT represent a complete set of the manufacturer's published data, nor does it represent a detailed specification. The preparation of a detailed specification is the responsibility of the design authority.
1. SYSTEM DESCRIPTION
  1. Two-ply roof membranes: the first ply consists of a base sheet; applied with hot asphalt, cold adhesive, fully heat welded, heat activated, spot adhered with adhesives and heat welded seams, self-adhered with self-stick products or loose laid with heat welded seams; the second ply consists of a cap sheet applied with hot asphalt, cold adhesive or heat welding.
  2. Single-ply roof membrane: install suitable membrane either loose-laid with seams heat welded in a ballasted system, spot adhered with adhesive, mechanically fastened and with heat welded seams, or fully heat welded to an approved substrate. Provided all of the seams are properly sealed, a single-ply system will function as well as a two-ply system. Since the workmanship factor can be variable, a two-ply system offers a safety factor when slopes are minimal.
2. COMPOSITION
  1. Binder: When a bitumen is modified by the addition of polymers, microscopic polymeric networks are created within the bitumen which markedly changes the characteristics of the materials. Only if the polymer has been thoroughly mixed with the bitumen and the elastomeric segments remain well dispersed at ambient temperatures, will the structure be continuous and rubbery and form entirely within the bitumen. In other words, these advantageous properties may be obtained only with a suitable degree of compatibility between bitumen and thermoplastic resin and by preparing the mixture with a certain type of bitumen.
  2. The binder in the roofing sheet is the critical component. It provides:
    - the waterproofing system
    - the elasticity
    - the aging characteristics
    - the flexibility at low temperatures
  3. Reinforcement: The characteristics of a quality binder can be enhanced by the proper choice of reinforcements. Reinforcement must counteract rupture in traction or compression, the limit of elasticity in traction or compression (undefined repeatable movements), or the limit of fatigue. To a lesser extent, reinforcements offer resistance to static puncture, stress induced by temperature variation, and wind effects. With few exceptions, however, it reduces the cold bending properties, the elasticity, and the elongation to rupture.
    While many types of reinforcements can be used, the most common are glass fibre, polyester and composite glass / polyester. Glass fibre reinforcement offers high tensile strength and excellent dimensional stability while polyester offers greater puncture resistance. The same type and weight of mat will give superior puncture resistance and tensile strength if saturated with elastomeric bitumen rather than an oxidized bitumen.
  4. Aging: Proper aging is contingent on the rate of modification, the compatibility of the bitumen with the polymer, and the blending being done correctly, with correctly blending the bitumen and SBS being the most important. Thick sheets display a much slower rate of aging than the thin sheets. Reinforcement does little to extend the aging process.
  5. Thickness: For heat welded application, where heat partially melts the binder, the reinforcement ensures the rigidity and the thickness ensures thermal inertia. Heat welded sheets should be no less than 3.0 mm (0.12"), measured without granules. Single ply membranes with heavy polyester / glass scrim reinforcement should have a minimum thickness of 4.0 mm (0.16"), measured without granules.
    Membranes applied with a mopping of hot bitumen or cold adhesive should have a minimum thickness of 2.3 mm. Extreme care should be taken when asphalt mopping membranes thicker than 2.3 mm since the heat capacity of the thicker membranes can drop the temperature of the mopping asphalt below required minimums before a satisfactory bond is achieved.
  6. Glaze Coat of Asphalt: Elastomeric membranes designed for torch welding should have additional mass for this purpose. Glazing the overlay and re-melting the glaze coat is a method designed to introduce additional mass to a system designed for asphalt application.
  7. Pour Coat and Gravel Surfacing: Pour coat and gravel surfacing can replace mineral granule cap sheets on roof systems with minimal slopes. This practice, however, can mask deficiencies and eliminates the possibility of refurbishing the system at a later date.
  8. Vapour Retarders: The function of a vapour retarder is a design consideration as it relates to climate and occupancy of the building.
  9. Cant Strips: Cants are not necessarily required where it is certain that no differential movement will occur at the joint; or in heat welded systems. However, they are considered standard practice in asphalt or adhesive applied assemblies. Whenever cant strips are used, do not adhere the membrane base sheet to them.
3. DELIVERY, STORAGE, AND HANDLING
  1. Deliver and store materials in original packages and containers with manufacturer's seals and labels intact.
  2. Store rolls on end; selvage end up; do not store in a leaning position.
  3. Elevate from contact with ground and moisture.
  4. Handle in such a manner to ensure membranes remain dry prior to and during installation.
4. SITE CONDITIONS
  1. Slope: when asphalt is used, slopes over 1:20 (5/8"in 12") require mechanical fixing of the top lap in the base sheet, using large-head galvanized roofing nails spaced at 150 mm (6") o/c staggered, and a fully torched cap sheet. Do not use asphalt on slopes over 1:12 (1" in 12").
    With torch applications, slopes over 1:3 (4" in 12") require mechanical fixing of the top lap. Run all plies parallel to the slope of the roof.
    
    Slopes over 1:3 (4" in 12") require nailers be incorporated into insulated systems.
    
    In all cases, contact the membrane manufacturer for slopes over 1:20 (5/8" in 12").
  2. Minimum ambient application temperature:
    - hot asphalt-applied - +5°C (+41°F) including wind chill
    - torch-applied - determined by worker's tolerance
    - adhesive-applied - contact membrane manufacturer
  3. Chemical incompatibility: SBS modified bitumen products are not compatible with coal tar pitch, and not resistant to oil and petroleum products. Contact Siplast / Icopal for specific requirements.
  4. Roof deck overlay: acceptable roof deck overlays include fibreboard, plywood, Dens Deck, asphalt recovery board or a minimum No. 40 glass-ply felt (CSA A123.2-M, Type CF).
  5. Insulations: modified bitumens can be used with most common insulations used for roofing and installed according to RGC Guarantee Standards.
  6. Minimum asphalt temperature: +205°C (+400°F) at the point of application.
  7. Adhesive application: the use of adhesive is intended to adhere the body of the membrane to the substrate, or to adhere membranes to themselves.
    Adhesives must never be used with membranes incorporating a metal foil.
    
    Base stripping plies can be heat welded, peel and stick or applied with cold adhesive.
    
    PA-828 adhesive is employed for fixing the membrane on vertical surfaces.
    
    In all cases, contact the membrane manufacturer.
5. STANDARDS AND APPROVALS (for specific membranes or assemblies consult manufacturer)
  1. Canadian General Standards Board: 37-GP-56M (Grade, Type, and Class vary with membrane)
  2. Underwriters Laboratories: Class A, B, C.
  3. Underwriters Laboratories of Canada: Referenced to _cUL_us
  4. Factory Mutual: Class 1 Fire and I-90 Windstorm or greater.
  5. Other: Avis Technique, Agreement, DIN, ASTM.
6. MANUFACTURER'S SERVICES
  1. Applicator training: Siplast membranes are applied by APPROVED APPLICATORS ONLY.
  2. Technical service: technical representatives are available for consultation and field training; owners, architects, and engineers are assisted in the selection and proper use of Siplast materials by technical representatives.
  3. Specification / Drawings: complete specifications and detail drawings are available upon request.
7. EQUIPMENT
  1. Torches: only torches with a trigger handle designed for the purpose of torching roofing material are acceptable.