10.1 fl. oz. Cartridge

20 fl. oz. Uni-pac sausage

SikaHyflex ® -150 LM
One part, low modulus, hybrid sealant


SikaHyflex-150 LM is a premium-grade, high movement, fast curing, one component, non-sag, elastomeric,hybrid sealant. Meets ASTM C-920, Type S, Grade NS, Class 50, use NT, M, A, G, O

Where to Use

  • For joints or gaps connecting dissimilar substrates – e.g. vinyl to concrete, aluminum to EIFS.
  • Window Perimeter
  • Expansion joints
  • Curtain Wall construction
  • For applications that require both paintability and adhesion to non-porous substrates
  • When easy cold weather application is desired


  • Fast skin time
  • Multi-substrate adhesion
  • Superior UV resistance and weathering
  • Color retention – white stays white
  • Can be over-painted soon after application (once skin has formed)
  • Very low VOC < 12g/L
  • Non-Staining


10.1 fl. oz. cartridge seals 12.2 linear ft. of 1/2 x 1/4 in. joint.

20 fl. oz. uni-pac sausage seals 24 linear ft. of 1/2 x 1/4 in. joint.

How to Use

Surface Preparation

The substrate must be clean, dry, frost free, sound and free of any oils, greases or incompatible sealers, paints or coatings that may interfere with adhesion.

POROUS SUBSTRATES - clean by mechanical methods to expose a sound surface free of contamination and laitance.

NON-POROUS SUBSTRATES - for cleaning non-porous substrates, use two rag wipe method using alcohol, xylene or an approved commercial solvent. Allow solvent to evaporate prior to sealant application.


SikaHyflex -150 LM is designed to obtain adhesion without the use of a primer; however, certain substrates may require a primer. Test by applying the sealant and/or primer sealant combination to confirm resultsand proposed application methods.

*In the situation where primer is needed on porous surfaces use Sika Primer 429. For non-porous surfaces contact Technical Services for proper recommendation.


The number of joints and the joint width should be designed for a maximum of ±25% movement of joint width at time of installation. The depth of the sealant should be 1/2 the width of the joint. The maximum depth is 1/2 inch (13mm) and the minimum is 1/4 inch (6mm). To control joint depth, use closed cell polyethylene, non-gassing polyolefin or open cell polyurethane backer rod. If joint depth does not allow for backer rod, use polyethylene bond breaker tape to prevent three-sided adhesion. Closed cell backer rod should be 25% larger than joint width; do not compress more than 40%. Open cell should be compressed 40%. Do not use open cell rod in horizontal on grade joints or with E.I.F.S. Ready to use, apply using professional caulking gun. Do not open product container until preparation work has been completed. Apply sealant using consistent, positive pressure to force sealant into the joint. Tool sealant to create a concave joint shape and achieve maximum adhesion. Dry tooling is recommended. DO NOT use soapy water or other liquids when tooling.


  • SikaHyflex -150 LM can be overpainted after a skin forms on the sealant
  • When overcoating with water, oil and rubber based paints, compatibility and adhesion testing is essential. Rigid paints and coatings may lose adhesion to elastomeric sealants due to their inability to accommodate joint movement.
  • Maximum depth of sealant must not exceed 1/2 in.; minimum depth is 1/4 in.
  • Do not cure in the presence of curing silicone or polyurethane sealants.
  • Use opened cartridges and uni-pac sausages the same day.
  • When applying sealant, avoid air-entrapment.
  • Since system is moisture-cured, permit sufficient exposure to air.
  • Light colors can yellow if exposed to direct gas fired heating element.
  • Do not tool with detergent or soap solutions.
  • Do not use in contact with bituminous/asphaltic materials.
  • Not intended for immersion
  • Not intended for structural glazing applications
  • Sealant may be applied below freezing temperatures if substrates are completely dry, frost free and clean. Contact Technical Service for more information.
  • Do not apply when substrate temperatures are below -20°F or above 130°F.
  • Not recommended for horizontal vehicular traffic.
  • Do not apply to substrates that bleed oil, plasticizers or solvent.
  • Do not apply to damp or wet substrates.
  • Lower temperature and humidity will extend tack free and cure rates
  • Allow treated wood to age six months before application.
  • The ultimate performance of SikaHyflex-150 LM depends on good joint design and proper applica- tion with joint surfaces properly prepared.