Glass wool–reinforced fiberglass polymer waterproofing membrane integrates an insulation layer (glass wool) with a waterproofing layer (fiberglass-reinforced polymer substrate). During installation, it is essential to ensure both waterproof sealing and the integrity of the insulation layer to prevent leakage and insulation failure caused by improper application. Given its “composite structure” characteristics, the following key considerations must be given particular attention during construction:

I. Pre-Construction: Foundation Preparation and Environmental Control

Surface preparation: Ensure the surface is smooth, dry, and clean.
Remove dust, oil stains, and other contaminants from the substrate; where necessary, apply a compatible primer (such as a cold-applied primer specifically formulated for polymer-modified sheet membranes) to enhance the bond strength between the membrane and the substrate.
Material and tool inspection: compatibility takes priority
Roll materials shall be stored in a cool, dry location, protected from direct sunlight and rain (as glass wool loses thermal insulation performance when it absorbs moisture, and polymer-based substrates are prone to deformation at high temperatures). Prior to installation, inspect the appearance of the rolls for any damage, wrinkles, or holes, and verify that the model and thickness comply with the design requirements.
   

II. During Construction: Core Processes and Quality Control
Follow the principle of “first apply to areas with lower drainage slopes and then to higher ones, and first at internal and external corners and then on large surfaces.” For roof applications, proceed from the eaves toward the ridge; for wall applications, extend from the floor upward. This approach helps prevent improper overlap of roofing membranes in areas prone to water accumulation.
Roof vent pipes and parapet bases: The roofing membrane shall be turned up to 100 mm below the parapet coping, or wrapped around the vent pipe to a height of at least 250 mm. The top shall be secured with a metal flashing strip and sealed with sealant to prevent rainwater from infiltrating through any gaps.
Construction joint treatment: For roll materials that are not fully laid on the same day, the ends shall be provided with an overlap length of ≥300 mm and temporarily secured with pressure strips. Prior to construction the following day, remove dust from the end portions, apply adhesive, and then perform the lap joint to prevent leakage due to gaps.

III. Post-Construction: Inspection and Finished-Product Protection

Real-time acceptance: Identifying leakage risks
Visual inspection: The membrane surface shall be free of damage, wrinkles, and blisters; lap joints shall be straight and tightly sealed; additional layers at details shall be firmly adhered; and the glass wool layer shall show no exposure or breakage.
Sealing performance testing: For roofs, a water-retention test may be conducted (with a water depth of 20–30 mm maintained for 24 hours, ensuring no leakage); for walls, a water-spraying test may be performed (using a spray nozzle to direct water along the wall surface for 30 minutes, with acceptance criteria being no water penetration on the interior side).