BMC SPE-AP

EPDM Membrane Protected Roofing System (Fully Bonded)


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Description:

This roofing assembly consist of EPDM (ethylene propylene diene terpolymer) single-ply rubber membrane fully bonded over the sand cement screed with bonding adhesives, covered by extruded polystyrene insulation board followed by separation layer and finishing layer of pre-cast concrete pavers or gravel.

Features and Benefits:

■    The membrane is maintained at a nearly constant temperature, close to the temperature of the building's interior; this minimizes the stresses on the membrane by reducing the harmful effects of thermal cycling and excessive heat.

■    The waterproofing membrane is protected from weathering, foot traffic and other types of physical abuse - both during and after construction.

■    Allow year-round construction since the roof is waterproofed first, then insulated.

■    Permit easily removal and re-installation of the ballast and insulation for making repairs or for constructing additional stories. In addition, a protected membrane roof provides an environmentally preferred option to reuse the insulation.

■    Allow for a range of ballast options - stones, precast paving slabs, green roof, interlocking stone or concrete - depending on use and aesthetic considerations.

■    Eliminate the need for a separate vapor retarder.

■    It offers exceptional durability to extend the life of the plaza or roof.

■    Characteristics that contribute to this superior overall system performance include;

-     Cyclical membrane fatigue resistance.

-     High resistance to ozone, weathering and abrasion.

-     Flexibility in low temperatures.

-     Superior resistance to extreme heat and fire.

-     Thermal shock durability.

-     Ultraviolet radiation resistance.

 

Installation Guidelines:

Sand cement screed laid to falls and cross falls (minimum 1% slope) trowel-applied smoothly finish.

Concrete upstands shall be dry, clean and smoothly finished; CMU (concrete Masonry Units) upstands must be properly plastered smoothly finished.

Membrane Placement and Bonding:

Unroll and position with stretching. Allow the membrane to relax for approximately hour before bonding. Fold the sheet back onto itself so half the underside of the membrane is exposed.

Apply the bonding adhesive to both the underside of the membrane and the substrate. Allow the adhesive to dry until it is tacky but will not string or stick to a dry finger touch.

Roll the coated membrane into the coated substrate while avoiding wrinkles. Brush down the bonded half of the membrane sheet with a soft bristle push broom to achieve maximum contact.

Fold back the unbonded half of the membrane sheet and repeat the bonding procedure.

Install adjoining membrane sheets in the same manner, overlapping edges approximately 4 inches. Do not apply bonding adhesive to the splice area.

Membrane Splicing:

Position membrane sheet to allow for required splice overlap. Mark the bottom sheets with an indelible marker approximately %” to f4” from the top sheet edge.

Apply EPDM primer to splice area and permit to flash off.

For end laps, apply sealing tape to the primed surface, remove the poly backing and roll the top sheet onto the mating surface.

Tape splices must be a minimum of 2-1/2” wide using 3” wide sealing tape extending 1/8” minimum to %” maximum beyond the splice edge.

Immediately roll the splice using positive pressure when using a 2” wide steel roller. Roll across the splice edge, not parallel to it.

This operation is repeated until the entire surface is covered/waterproofed.

Membrane Termination:

Upper ends of membrane shall be terminated above roof finishing level (minimum 150mm) using extruded aluminum termination pressure bar, mechanically fastened at 300 O.C., and completely sealed with mastic sealant.

Water Test:

The water test can be done with flood testing. Minimum water head level and duration of the water test as per project requirements and engineer's instruction must be followed.

Plug the drains and provide necessary barriers to contain flood water to avoid pressure and damage the membrane.

Removal of water and cleaning/drying of the tested area must be done after the water test is completed.

Thermal Insulation:

Apply extruded polystyrene rigid board thermal insulation, loose laid with rebated edges over the completed and water tested waterproofing membrane system.

Separation Layer:

Apply a layer of non-woven geotextile separation layer with minimum of 100mm wide overlaps, loosely laid, above the installed waterproofing membrane, minimum of 50mm wide overlaps to the adjacent sheets.

Finishing Items:

Application of finishing items above the separation layer (i.e.: Pre­cast Concrete Pavers / Gravel) shall be provided & installed as project specification requirements.

Storage Conditions:

Products must be stored in their original packaging under cool and dry conditions. They must be protected from direct sunlight & rain.

Adhesives, primers and sealants should be stored in a cool shaded storage or in air-conditioned containers.

 

Criteria

System Property

Membrane

Membrane Type

Single-Ply Synthetic Rubber

Application Type

Fully Bonded

Membrane Options

Reinforced / Non-Reinforced

Thickness Options

45mils / 60mils / 75mils / 90mils

Roll Size (W x L)

10-50ft x 200ft

Insulation

Insulation Type

Extruded Polystyrene Insulation Board

Density Options (kg/m3)

32-35/36 / 40 / 45 / 48

Thickness

Variable, As Per Project Requirements

Separation Layer

Separation Layer Options

Non-Woven Polyester or Polypropylene Geotextiles / Polyethylene Sheets

Separation Layer Density

Options

Variable, As per Project Requirements

Finishing

Finishing's Options

Pre-cast Concrete Pavers / Gravel