Waterproofing system
Double-Layer SBS Basement Waterproofing
A double-layer SBS basement system installs two plies of SBS-modified bitumen membrane to provide redundancy under hydrostatic risk. Continuity at the raft, walls, and joints is mandatory. Petroseal uses PetroGrip SBS within designs that call for multi-layer below-grade protection.
System build-up
- Primer
- First SBS ply
- Second SBS ply (staggered laps)
- Protection board / screed before backfill or slabs
Substrate
- —Raft blinding and vertical walls per design
Critical details
- —Staggered overlaps
- —Raft-to-wall transition
- —Waterstops at pour joints
Limitations
- —Does not replace drainage design where specified
Installation sequence
- Design ply count
- Install base ply
- Install cap ply
- Protect
- Inspect
Related applications
- Basement Waterproofing Pakistan
Basement waterproofing in Pakistan typically requires a positive-side membrane system designed for hydrostatic pressure,…
- Raft Waterproofing Pakistan
Raft waterproofing places a designed horizontal membrane assembly under or around the raft according to the structural w…
- Foundation Waterproofing Pakistan
Foundation waterproofing protects structural concrete against ground moisture and hydrostatic pressure. Petroseal uses b…
Related products
- PetroGrip SBS
SBS-modified torch membrane—3mm and 4mm with plain, aluminum, or granular surfacing.
- PVC Waterstoppers
PVC water-stops for watertight concrete construction joints.
Related projects
- Emporium Mall
Johar Town, Lahore
Technical downloads
- PetroGrip SBS Waterproofing Membrane TDS
Polyester-reinforced SBS-modified torch-applied bitumen membrane — 3 mm nominal thickness, 60/70 bitumen base.
Technical guides
- Basement Waterproofing with Bitumen Membrane Systems
Design and install basement waterproofing with PetroGrip SBS torch membrane and PetroSelfGrip sheets—substrates, laps, protection boards, and Lahore-manufactured systems for nationwide projects.
FAQ
- When is double-layer required?
- When the waterproofing designer specifies redundancy for groundwater or project standards. Not every basement needs two plies.