JX260 Asphalt-based Pre-applied Waterproofing Membrane is a self-bonded modified rubber asphalt waterproofing material with polyester reinforcement as the core carrier. One side is coated with a self-adhesive layer that is surface-treated with an anti-stick or low-tack material, enabling chemical reaction and bonding with cast-in-place concrete.

Scope of Application

Suitable for bottom slab waterproofing of underground building structures and cut-and-cover metro projects, as well as basement side wall waterproofing with external/internal-facing installation method.

Product Specifications

Type PY: 4.0mm

Performance Standard

《Pre-applied Waterproofing Membranes》GB/T23457-2017 (Type PY)

Product Features

• High tensile strength, large elongation and strong puncture resistance, minimizing membrane damage on construction sites.

• Cold application, no open flame required. Low substrate requirements, convenient and fast installation.

• The membrane chemically reacts and fully bonds with cast-in-place concrete, completely preventing water migration between layers for more reliable waterproofing performance.

• After pre-applied membrane installation, rebar can be directly tied and concrete poured without a protective layer, shortening construction period and reducing costs.

Construction Workflow

Substrate Cleaning → Detail Reinforcement → Mark Reference Lines for Membrane Laying → Membrane Installation → Membrane Overlap → Detail Sealing → Self-Inspection & Acceptance → Handover of Working Surface

Construction Method

• The substrate surface ought to be solid, dense, flat and free of debris. The substrate may be damp but must have no standing water. Internal/external corners at horizontal-to-vertical transitions shall be formed into uniform arcs as required.

• Apply additional reinforcing layers at detail joints per relevant specifications or design requirements. General areas shall be fully bonded; stress-concentrated areas shall be loosely laid per specification requirements.

• Horizontal installation: On the approved substrate surface, reserve the lap width according to the membrane width and snap the reference lines. Position and loosely lay the membrane on the substrate, then adjust its alignment. The polyethylene film side faces the substrate, while the release film on the self-adhesive layer faces the workers. Roll the membrane while laying to expel air from beneath it. Lap joints are self-bonded.

• Vertical and inclined surface installation: Position the membrane on the vertical substrate along the snapped reference line, with the self-adhesive layer release film facing the vertical structure. Secure the membrane at lap positions using special concrete nails. Peel off the release film on lap edges and perform long-edge and short-edge laps with overlap width ≥80mm. Ensure all nail heads are covered by adjacent membrane. Immediately roll laps with a press roller for sealing, then seal all long and short edge laps with sealant.

• Vertical end termination can be fixed with termination bars and sealed with sealant. After all membrane installation, the release film on the upper surface of the waterproof layer can be removed.

• When the substrate is damp or ambient temperature is low, appropriate heating can be applied during membrane lapping.

Transportation & Storage

Products of different types and specifications shall be piled up separately without mixing. Avoid direct sunlight and rain, maintain good ventilation. Storage temperature shall not exceed 45℃. For horizontal storage, stack height shall not exceed 5 rolls; vertical storage shall be single layer. Prevent tilting or lateral pressure during transportation; cover with tarpaulin if necessary. Under normal transportation and storage conditions, shelf life is at least 1 year from the production date.