Waterproofing Membrane and Expansion Joint Warranty, Hydrotech 6125 and Emseal RoofJoint

Waterproofing Membrane Warranty–Hydrotech/Emseal

Waterproofing and roofing membranes are only as good as their weakest link. If not properly specified, expansion joints that bisect waterproofing membranes can be that weak link. A waterproofing membrane warranty from a single source that covers both the membrane and the expansion joint is now available to bridge this gap. And, it comes from two of the most trusted waterproofing brands–American Hydrotech and Emseal–brought together under common ownership by Sika Corporation.

Hydrotech and Emseal are pleased to announce that when Emseal’s RoofJoint product is used in conjunction with Hydrotech’s Monolithic Membrane 6125® (MM6125®) waterproofing/roofing membrane, Hydrotech can provide a true single source Watertightness Warranty for up to 20 years.

Emseal’s Roofjoint is a dual-seal, double-flanged, extruded thermoplastic (nitrile PVC alloy) roof expansion joint system that easily accommodates deck movement and provides redundant levels of integration with Hydrotech’s MM6125 waterproofing/roofing membrane. RoofJoint also addresses specific detailing conditions to ensure continuity of seal, such as tees, crosses, parapet details, and roof to wall transitions. All connections in Roofjoint components are welded and reinforced to ensure watertight integrity.

Roofjoint is marketed and sold through Sika Emseal’s own sales channels. Emseal will provide the necessary support to the designer as well as to Hydrotech’s authorized applicators that install it.

Hydrotech Monolithic Membrane 6125® (MM6125®) hot fluid applied rubberized asphalt, is the 50-year standard for buried waterproofing applications. Emseal’s RoofJoint has redefined expansion joint waterproofing in those same applications.

Now, as part of the Sika family, American Hydrotech will include the Emseal RoofJoint expansion joint under their comprehensive waterproofing membrane warranty within their Ultimate Assembly and their Garden Roof Assembly (consult Hydrotech).

With this comprehensive waterproofing membrane and expansion joint warranty, waterproofing, roofing and building envelope consultants, architects, and engineers can specify with confidence a comprehensive solution on behalf of their property owner clients. Roof assemblies including garden roof, green roof, plaza podium deck, and blue roof storm-water management roofs have just received the missing piece to worry-free performance.

Hydrotech has developed a set of MM6125 waterproofing/roofing guideline specifications and guideline details specific to the Roofjoint product–Request These Now.

Sika Emseal’s Roofjoint is marketed and sold through Emseal’s own sales channels. Sika Emseal will provide the necessary support to the designer as well as to Hydrotech’s authorized applicators that install it. Emseal’s Roofjoint product data sheet and installation guidelines provide specifics.

Waterproofing Membrane Warranty–Hydrotech/Emseal


  • Absolutely the most positive, watertight tie-in to MM6125 hot applied rubberized asphalt waterproofing membrane
  • Redundant sealing across the joint opening
  • Allows drainage across the joint opening
  • Redundant dual-level roof-membrane integration
  • Redundant fastening—adhesion & mechanical termination bar
  • Factory heat welded transitions at tees, crosses, angles, roof-to-wall details, parapet wall details, etc.
  • Watertight transition to Seismic Colorseal wall joints using RoofJoint Closures
  • Uniquely addresses wall joint to roof joint interface
  • Continuity of seal through transitions
  • High movement


  • Flat roofs
  • Sloped roofs
  • Green roof, garden roof, vegetative roofs
  • Blue roof stormwater management systems
  • Plaza/podium deck and split-slab assemblies
  • Roof to wall details
  • Roof to wall expansion joint transitions

U.S. Patents

US Patent: 10,851,542
US Patent: 9,850,662
US Patent: 9,739,050
US Patent: 9,322,163