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REINFORCES TURNUPS, CORNERS, FLASHINGS AND OUTLETS

StretchSeal HF Waterproofing System


The flat field of a waterproofed roof rarely leaks. It's the details that give way — the corner where the slab meets the parapet wall, the flashing that was never properly sealed, the outlet where the membrane terminates. The StretchSeal HF System reinforces exactly those points on concrete and cement surfaces before they have a chance to fail.

REINFORCEMENT WATERPROOFING SYSTEM

COMPOSITION OF THE STRETCHSEAL HF SYSTEM

The system is used on concrete and cement surfaces only. Penetrar primes the substrate. Where applicable, a 45° cement flashing is installed at the base of the parapet wall first. HydroSeal HF is then applied, the membrane embedded and a second coat applied to encapsulate, reinforcing every corner, turnup, flashing and outlet before the full waterproof topcoat goes over the whole surface.

StretchSeal HF Waterproofing System

Application Steps

1/ Concrete or Cement Substrate

PREPARE - The surface must be clean, dry and structurally sound. Remove all loose material, dust and debris. The StretchSeal HF System is used on concrete and cement surfaces only. It's not designed for metal.

45° CEMENT FLASHING - At all parapet wall bases and right-angle wall-to-slab junctions, a 45° cement fillet is installed. It replaces the sharp 90° corner with a sloped transition — giving the StretchSeal Membrane a surface it can conform to without bridging a hard angle under tension.

PRIME - PENETRAR - Applied to the full concrete or cement surface before the detail work starts. Penetrar binds the substrate and keeps the polymer content of the HydroSeal HF in the top layer where it's most effective. Don't skip it on porous or dusty concrete.

2/ HydroSeal HF

FIRST COAT — WET BED - Applied over the detail area — the corner, flashing, outlet casing or turnup. This is the wet bed the membrane is pressed into. Work in manageable sections and don't let the coat skin over before the membrane goes on.

3/ STRETCHSEAL MEMBRANE

EMBED MEMBRANE - Laid into the wet HydroSeal HF and pressed firmly to remove all air pockets. It needs full contact — any section sitting on the surface rather than embedded in the product is a weak point. Cut to size for each detail. Overlap adjacent pieces by at least 5cm.

4/ HydroSeal HF — 2 X Topcoat

OVERCOAT — ENCAPSULATE - A second coat of HydroSeal HF is applied over the embedded membrane to fully encapsulate it. Allow to dry completely. The detail is now reinforced and ready for the full-surface topcoat system above it.

FULL SURFACE TOPCOAT - Two coats of HydroSeal HF are applied over the full waterproofed surface as the final seamless membrane. The first coat once touch dry and walkable. The final topcoat once the first is completely dry.

HOW IT WORKS

REINFORCE THE DETAILS. THEN COAT THE SURFACE.

A waterproof coating applied directly over a sharp 90° corner or around an outlet casing isn't properly sealed. It's bridging the geometry under tension. That tension leads to cracking, and cracking leads to water finding its way through at exactly the point where you least want it. The StretchSeal HF System solves this before the topcoat goes on.

All the detail work happens first. Every corner, turnup, flashing and outlet is individually reinforced with StretchSeal Membrane embedded in HydroSeal HF before the two full-surface topcoats are applied. By the time the topcoat goes on, every weak point in the system is already a reinforced zone — not a liability.

StretchSeal Waterproofing System v1

Where StretchSeal HF Is Used

STRETCHSEAL HF SYSTEM AT WORK

Three concrete and cement installations where the StretchSeal HF System reinforced the critical detail points before the full waterproof membrane was applied.

Parapet Corners and Outlets Reinforced — New Concrete Roo

A new flat concrete roof slab on a residential home in Pretoria was waterproofed using the full ArmTec HyperFlex system. Before the mesh went down, the StretchSeal HF System was used on all four parapet corners, both wall turnups and the three full bore drainage outlets. Penetrar was applied first, 45° cement flashings installed at the parapet bases, and every corner and outlet reinforced with StretchSeal Membrane embedded in HydroSeal HF. The ArmTec mesh and two topcoats of HydroSeal HF followed above. Every detail point on that roof is properly sealed.

Flashings and Turnups Sealed — Commercial Flat Roof

A commercial building in Johannesburg had a flat cement roof with multiple plant rooms, a lift motor room and several wall protrusions that created a complex pattern of flashings and vertical turnups. Every one of these was a potential water entry point. The StretchSeal HF System reinforced all flashings and turnups with membrane embedded in HydroSeal HF before the two-coat HydroSeal HF topcoat was applied over the full surface. The building hasn't had a water call since the installation.

Full Bore Outlets Sealed on Waterproofed Balcony

A waterproofed balcony in Centurion had been leaking around both drainage outlets for over a year despite two previous attempts to seal them with coating alone. The outlets were full bore connections into PVC pipework and a coating without membrane reinforcement can't seal correctly around a PVC casing. The StretchSeal HF System was used to embed StretchSeal Membrane directly onto each outlet casing using HydroSeal HF — properly sealing the membrane termination point at each outlet. The leaks stopped immediately.

WORK WITH US

Let our technical support team help you find the right solution for your application.

WATERPROOFING SERVICES

WATERPROOFING SERVICES NEAR YOU

Torchon Maintenance

Renew or maintain your current waterproofing system without removing it. The Armtec Renew system has excellent adhesion and can be applied directly over existing waterproofing systems. The Armtec Renew system can be applied directly onto bituminous substrates or existing torchon membrane. Surface will not delaminate when correct application procedures has been adhered to.

Roof Slab Waterproofing

The seamless eco-friendly concrete roof slab waterproofing system from SealPro Coatings can be installed on new and existing roof slabs. The waterproofing system is a high-performance universal waterproofing system specifically developed for long term protection. Applying the SealPro waterproofing system will guarantee a seamless waterproofing system that is UV resistant and durable.

Balcony Waterproofing

Balconies, like all other parts of a property, require waterproofing. Whether the balcony is constructed using a concrete slab or timber, if water has penetrated the top surface, it will find or cause weakness. This will result in water damage to the ceiling or walls below. The solution to this problem is to waterproof the balcony. Explore the Armtec under-tile waterproofing systems for more information.

Tile Roof Waterproofing

The tile roof waterproofing system is used to waterproof roof ridge, valley, flashing & parapet walls. The system will seal your roof and help protect against leaks and weathering. The tile roof waterproofing system is UV stable, weather-resistant, durable, long-lasting and low maintenance.

Metal Roof Waterproofing

Our approach to restoring and waterproofing metal roofs offers a long-term solution, with no exposure of brittle materials to the elements, providing you with a leak-free roof for years to come. The waterproofing system can be used to seal ridges, valleys, joints, overlaps & screwlines.

Ponds, Dams & Reservoirs

The waterproofing system can be used to seal ponds, cement dams, water features, birdbaths and fountains. When fully cured the waterproofing system forms an impervious, flexible and aesthetically pleasing waterproofing membrane which enhances the look of the pond or water feature.

CONTACT

NEED TO KNOW MORE?

LET'S TALK.

The success of any project depends on the type of product and the correct application of the solution. The SealPro technical support team has experience in all specialised coatings we supply and can help you to find the correct product & solution for your application.

+27 60 997 6364

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