815MEMBRANE WATERPROOFING

815.01 Description. This item shall consist of the application of

a membrane waterproofing, consisting of a membrane of the type designated, according to these specifications and i n conformity with the plans.

815.02 Types of Membranes. The membrane shall consist of

one of the following types: Type A. One asphalt primer coat, two layers of asph alt-treated cotton fabric, and three moppings of asphalt. 829 Type B. One asphalt primer coat, two layers of asph alt-treated felt, one middle layer of asphalt-treated cotton fa bric, and four moppings of asphalt. Type C. A 4 mil (0.10 mm) (minimum) polyethylene fi lm laminated to a rubberized asphalt mastic material ( total thickness of 50 mils [1.3 mm], minimum). A primer shall be used as specified by the manufacturer and a rubberized asphalt mastic shall be used for sealing seams and exposed edges. Type D. One-part, cold applied, asphalt modified, u rethane coating. Final cured thickness of this membrane sh all be approximately 50 mils (1.3 mm) (multiple applicatio ns may be required to obtain this final cured thickness). Th is material shall not be used with asphalt impregnated joint filler. Type E. Two layers of trowel applied, fiber-modifie d asphalt compound, either solvent based or a mineral colloid emulsion, and one layer of asphalt-treated cotton fabric placed b etween the layers of the modified asphalt. Other types of membrane may be used subject to the approval of the Engineer. When the type is not specified on the plans or in t he Special Provisions, the Contractor may select any of the ab ove types of membrane.

815.03 Materials. (a) Asphalt. Asphalt shall be mopped-on

material and shall be the same type of asphalt as t hat with which the felt or fabric is treated.

815.04 Construction Requirements. At the time of application,

surfaces to be membrane waterproofed shall be dry a nd clean and the temperature of the surface shall not be less th an 50°F (10°C). Projections shall be removed. There shall be no pu nctures, depressions, pockets, or folds in the horizontal su rfaces of the finished waterproofing. Concrete curing requirements shall be completed bef ore the waterproofing is applied. On vertical surfaces, the strips of fabric or felt may be laid vertically. On sloping surfaces, the strips shall be placed shingle fashion, beginning at the lowest part of the surfac e to be waterproofed. Sufficient fabric or felt shall be a llowed for a suitable lap or anchorage at the upper edge of the surface t o be waterproofed. Side laps shall not be less than 2" (50 mm) and end laps shall be staggered with laps not less than 12" (300 mm) or a s recommended by the manufacturer. Surfaces to be waterproofed with Types A or B membr anes shall be given one coat of asphalt primer before the firs t mopping. The 831 primer shall be applied to the surface to give a un iform coating. The prime coat shall be applied approximately 24 hours before applying the waterproofing membrane and shall be dry before the first mopping is applied. Surfaces to be waterproofed with Types A or B membr anes shall be mopped in sections. While the first mopping of asphalt is still hot, a strip of fabric or felt shall be placed on t he mopping and pressed into place. Each mopping thereafter shall be applied so that it will completely cover and seal the fabric or fel t. The amount of asphalt used for each mopping shall be not less tha n 4½ gallons per 100 square feet (1.8 L/sq m) of surface. Asphalt h eating kettles shall be equipped with armored or electronic sensin g, digital readout thermometers so placed that the temperature of the asphalt can be readily determined at any time. The temperature at the time of application shall be in the range recommended by the manufacturer. Patching shall not be accomplished without permissi on of the Engineer. Where patching is permitted for repair o f defective waterproofing, it shall extend at least 12" (300 mm ) beyond the outermost edge of the defective area. Each succeed ing ply of the patch shall extend at least 3" (75 mm) beyond the p receding ply. At construction joints, where specified, the primer (if required) shall be omitted for a width of 18" (500 mm) of the surface and a strip of insulating paper laid thereon before water proofing is applied.

815.05 Method of Measurement. Membrane Waterproofing

will be measured by the square foot (square meter). The area for measurement will be the entire finished surface are a actually covered but shall not exceed the limits shown on th e plans or authorized by the Engineer.

815.06 Basis of Payment. Work completed and accepted and

measured as provided above will be paid for at the contract unit price bid per square foot (square meter) for Membra ne Waterproofing of the type specified, which price sh all be full compensation for furnishing and applying materials; and for all labor, equipment, tools, and incidentals necessary to complete the work. 832 Payment will be made under: Pay Item Pay Unit Membrane Waterproofing (Type___) Square Foot (Square Meter)

MEMBRANE WATERPROOFING in other states

• Vermont 519 · MEMBRANE WATERPROOFING