Liquid-applied versus sheet membrane
Sheet membranes—PetroGrip APP and SBS torch rolls—excel on large flat fields with trained torch crews. Liquid polyurethane chemical coatings from Petroseal form seamless, flexible films where geometry is irregular: multiple penetrations, curved curbs, stair landings, and tie-ins to metal flashings. PetroFlooring is a coating system, not thermal insulation; pair it with Green Insulation XPS or PUF when the specification includes insulated decks.
On terraces with many door thresholds and AC stands, a multi-coat polyurethane build-up can be faster to detail than cutting dozens of membrane patches—provided substrate preparation and primer compatibility are controlled.
System build-up and coverage
| Layer | Role |
|---|---|
| Surface prep | Clean, dry concrete; repair cracks and voids |
| Primer | Bonds coating to substrate; type per datasheet |
| Base / top coats | Build dry film thickness for water tightness |
| UV-stable topcoat | Required on fully exposed roofs |
Typical coverage rates appear on Petroseal submittals—often 1.5–2.0 kg/m² for multi-coat systems. Single-coat shortcuts on full UV exposure rarely match consultant performance requirements in Punjab and Sindh summers.
Terrace and balcony detailing
Positive fall to drains must exist before coating. Reinforce inside corners and pipe penetrations with fabric embedded in wet coat where the detail drawing requires. Allow full cure before tile beds or pedestrian finishes—premature trafficking causes pinholes and delamination at upturns.
At transitions to torch-applied main roof fields, show whether membrane laps over coating or coating ties into membrane with approved primer—mixed systems fail at undocumented handoff lines.
Industrial floors and light roof repair
Chemical-resistant polyurethane variants suit light industrial floors and service corridors where abrasion and cleaning chemicals matter. For large new exposed roofs, consultants still often prefer PetroGrip sheet cap sheets; coatings win on repair overlays and complex infill zones on existing buildings.
Petroseal supplies PetroFlooring nationwide from Lahore with technical support at 0321 8489737 and datasheets at petrosealenterprises.com.