APP and SBS are the two polymer families used to modify bitumen waterproofing membranes, and the choice between them is simpler than it looks: APP membranes excel in heat and UV, which makes them the default in Egypt and the Gulf; SBS membranes excel in elasticity and cold, which makes them the choice wherever the structure moves or temperatures drop.
What the letters actually mean
- APP (Atactic Polypropylene) turns bitumen plastomeric: a higher softening point, strong UV resistance and a firm, weather-facing surface. Applied by torch.
- SBS (Styrene-Butadiene-Styrene) turns bitumen elastomeric: rubber-like stretch and recovery, and flexibility that survives freezing temperatures.
Side by side
| Property | APP membranes | SBS membranes |
|---|---|---|
| Behaviour | Plastomeric (firm) | Elastomeric (rubbery) |
| Strength in | Heat, UV, sun-exposed roofs | Movement, fatigue, cold |
| Typical use | Exposed and covered roofs in hot climates | Bridges, joints, cold stores, moving structures |
| Insutech range | InsuGrand, InsuFort, InsuSol, InsuUltra | InsuPrene, InsuBend, InsuMeric |
| Self-adhesive option | — | InsuStick family (flame-free) |
Both families come on non-woven polyester (PES) or fiberglass (FG) carriers in thicknesses from 1.5 to 6 mm — carrier and thickness matter as much as the polymer for the membrane’s life.
Which one for your project?
- Exposed flat roof in a hot climate → mineral-finished APP: see the exposed roof system.
- Roof under screed, tiles or a garden → plain APP: see non-exposed roofs and green roofs.
- Bridge decks, expansion-prone structures → SBS: see the bridge deck system.
- No-flame sites, timber decks, details → self-adhesive SBS.
What actually drives the price
Between two membranes of the same family, cost differences come from thickness (a 5 mm roll carries more compound than a 3 mm one), carrier type and weight, surface finish (mineral and foil finishes cost more than plain film) and certification level. Comparing brands on price per roll without matching those four factors is comparing different products.
Buying membranes in Egypt or for export
Insutech manufactures both APP and SBS membranes in Egypt since 1987, with an annual capacity of 38,000,000 m² — among the largest bitumen membrane operations in Egypt and the region — CE-marked and exported to 105+ countries. Datasheets are on every product page and in the Download Center.
Not sure which family your project needs? Request a quote — send us the roof or structure details and our engineers will specify APP, SBS or a combination.