Retrofit Waterstop Systems

PVC Retrofit Waterstop Systems for Sealing New-to-Existing Concrete Joints

Sika Greenstreak PVC Retrofit Waterstop Systems are high-performance waterproofing solutions engineered to seal construction joints where new concrete is poured against an existing concrete structure. Unlike traditional embedded PVC waterstops that are cast into fresh concrete during initial construction, retrofit waterstops are surface-mounted and mechanically anchored to the face of cured, existing concrete, making them the go-to choice for concrete repair, rehabilitation, structural expansion, and tie-in projects where embedding a conventional waterstop is not possible. Each retrofit waterstop system combines a flexible PVC profile with stainless steel batten bars, stainless steel anchor bolts, and a structural epoxy gel (such as Sika 7300) to deliver a secure, watertight bond to the existing concrete substrate while the opposite flange is embedded into the new concrete pour, forming a continuous watertight diaphragm across the joint.

How Retrofit PVC Waterstops Work

Retrofit waterstop systems use a dual mechanical and chemical anchoring method to ensure long-term joint integrity. The prepared surface of the existing concrete is coated with a high-strength structural epoxy gel, the PVC waterstop flange is pressed into place, and a stainless steel batten bar is positioned over the flange and fastened down with stainless steel anchor bolts. This combination of epoxy bonding and mechanical fastening creates a watertight seal that resists hydrostatic pressure, chemical exposure, and joint movement. The flexible PVC profile accommodates limited lateral, transverse, and shear movement, making retrofit waterstops suitable for both static joints and joints with minimal anticipated movement.

Sika Greenstreak Retrofit Waterstop Profiles

Sika offers a complete range of retrofit waterstop profiles to match the hydrostatic, structural, and dimensional requirements of nearly any project. The 581 PVC Retrofit Waterstop features a compact 3 11/16″ profile width and a lightweight 1.51 lb/ft design, making it ideal for tight retrofit applications that still demand reliable waterproofing performance. The 609 PVC Retrofit Waterstop offers a 6″ profile width and a heavy-duty 2.92 lb/ft weight, delivering robust performance for vertical and horizontal joints in water treatment facilities and below-grade concrete restoration. The 655 PVC Retrofit Waterstop features a 3″ PVC profile with a 7/16″ overall thickness, designed to flex with joint movement while maintaining a watertight diaphragm in tanks, vaults, retaining walls, and tunnels. The 667 PVC Retrofit Waterstop provides a heavy-duty 9″ profile rated for up to 150 feet (448 kPa) of hydrostatic head pressure, making it the preferred choice for the most demanding water containment and structural joint applications. Each profile is supplied in 10-foot pieces with the required stainless steel batten bar and anchor bolt hardware.

Common Applications for Retrofit Waterstops

Retrofit PVC waterstop systems are specified across a wide range of infrastructure, industrial, and commercial concrete projects, including water treatment plants, wastewater treatment facilities, potable water tanks, reservoirs, aqueducts, dams, lock systems, tunnels, culverts, bridge abutments, flood walls, retaining walls, foundations, vaults, containment structures, secondary containment basins, and below-grade concrete repair and rehabilitation projects. Anywhere new concrete must be tied into existing concrete with a watertight seal, a retrofit waterstop is the proven solution.

Why Choose Sika Greenstreak Retrofit Waterstop Systems

Sika Greenstreak is the industry leader in PVC waterstop technology, and the retrofit waterstop line is manufactured from prime virgin PVC that meets or exceeds the physical property requirements of Army Corps of Engineers PVC Waterstop Specification CRD-C 572-74. All Sika PVC retrofit waterstops are NSF-61 certified for potable water contact, offer outstanding chemical resistance to waterborne chemicals, and deliver superior hydrostatic pressure resistance for long-term performance. The included stainless steel hardware resists corrosion in wet, chemically aggressive, and below-grade environments, while factory-fabricated transitions, intersections, and fittings are available to reduce field welding errors and ensure continuous waterproofing integrity. With multiple profile sizes, proven performance, and the backing of the Sika Greenstreak name, retrofit PVC waterstop systems give engineers, specifiers, and contractors a complete, reliable solution for sealing joints between new and existing concrete.