SMARTCOAT™ 370 UltraSeal is a silyl-modified polyether high performance, multi-purpose, low VOC, single component adhesive/sealant designed for bonding and sealing a wide range of porous and non-porous construction materials. Not intended for use on TPO. SMARTCOAT 370 forms a superior waterproof seal to most roofing materials including metal flashings, copings and skylights. Can be applied to damp or dry surfaces. Paintable by latex-based paints or SMARTCOAT 400 Series Coatings approximately one hour after application. Will not crack, shrink or peel. Easy to gun and tool for quick application. Meets or exceeds the requirements of ASTM C920 Type S, Grade NS, Class 50 and TT-S-00230C.

Technical Information




10.1 oz. Tube, Carton of 24


28 lbs. per carton

Application Temperature

0˚F - 140˚F



Cure Time

24-48 hours

Hardness Shore A


Temperature Resistance After Cure

-75˚F - 350˚F



Coverage: Approximately 25 lineal feet for 1/4" width and 1/4" depth joint. 

Precautions: Substrate chemistries and structures can interfere with adhesive performances of the sealant. Adhesion Test is MANDATORY to assess any adhesion and sealing characteristics. This must be done pre-installation to avoid potential failures. 

1. Surface must be free of dirt, dust, oil, old caulking or other contaminants. For best results apply when temperature is above 32ºF. Maintain SMARTCOAT 370 at room temperature to ensure easy gunning. 

2. Cut nipple on cartridge and cut spout to desired bead size at 45º angle and load cartridge into caulking gun.

3. Gun sealant firmly into void to provide solid fill. 

4. Smooth sealant immediately with sponge or cloth dampened with a mil dish detergent solution. Do not use mineral spirits, this will inhibit the cure. 

5. Promptly clean tools and excess material with isopropyl alcohol before caulk cures. 

6. For best results if used indoors, sealant must be painted. 

For more information, see published SMARTCOAT specifications at


Warranty Details

CertainTeed offers three asphaltic low-slope roof system warranty options: Limited Warranty on Materials, Integrity Roof System Limited Warranty, and Integrity Roof System No Dollar Limit (NDL) Limited Warranty. CertainTeed warranty durations are based on a combination of system specification and product selection. Please download an overview of these warranty options for details. Consult with your contractor or CertainTeed Territory Manager to determine which warranty is best for your project.     

CertainTeed offers standard asphaltic low-slope roof system warranty durations between ten and twenty-five years. Additionally, Gold Star Contractors can increase warranty durations by 25% by engaging in an Integrity Maintenance Agreement with their client.

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