SILCOR® Top Coat 70 Data Sheet

Two-component, aliphatic urethane-based top coat for use with SILCOR® liquid waterproofing membranes

Product Description

SILCOR® Top Coat 70 is a two-component, UV protective coating, formulated specifically to protect SILCOR® waterproofing membranes in permanently exposed upturn and flashing applications.

Product Advantages

  • Prevents discoloration of SILCOR® membranes in upturn and flashing applications
  • Color stable and UV resistant
  • Frost and weather resistant
  • Easy to apply by brush or roller
  • Extends allowable exposure limits for SILCOR® membranes


UV protection of SILCOR® liquid waterproofing membranes where left permanently exposed to UV radiation in upturns and flashing applications.

SILCOR® Top Coat 70 is not intended for use in fully exposed and trafficked membrane applications, though it can be used to extend the exposure limitation for SILCOR® membranes.

Suitable for use as part of the SILCOR® system in the following applications:

  • Plaza decks
  • Split slabs 
  • Green roofs
  • Planters
  • PRMA applications


Surface preparation

  • The membrane surface must be clean, sound, free of dust, laitance, sealers, grease or any other contaminants that might reduce adhesion.
  • SILCOR® Top Coat 70 should be applied to solidified SILCOR® waterproofing membranes within 24 hours of membrane installation.
  • SILCOR® membrane temperature should exceed the dew point temperature by a minimum of 5°F prior to SILCOR® Top Coat 70 application.


  • Add the complete quantity of the B-component to the A-component to ensure the correct mixing ratio.
  • Mix with a slow turning mixer (less than 300 RPM) for three minutes in order to obtain a homogeneous mixture. Scrape around the sides and base of the pail to ensure thorough mixing.  
  • Never add fresh material to partially cured material. Never mix more than one batch at a time in a single container. Heat is generated when B-component and A-component are mixed. Do not leave the mixed materials in the container or cure quantities in excess of recommendations, as this may cause a premature exothermic reaction.


  • Apply SILCOR® Top Coat 70 to the surface by brush or roller immediately after mixing to ensure coverage of the entire surface.
  • Broadcast dry, iron-free sharp, white quartz sand into the wet SILCOR® Top Coat 70.
  • Broadcast sand to full saturation.
  • Remove the surplus sand and partially bonded particles after the SILCOR® Top Coat 70 is dry to touch.
  • Apply the second coat of SILCOR® Top Coat 70 to thoroughly encapsulate the aggregate.
  • Ambient application temperature range: 40°F to 90°F.


  • SILCOR® Top Coat 70 cure time is 24 hours at 70°F.
  • Application must be protected from precipitation for at least four hours.

Repairs or Maintenance

  • Damaged areas should be repaired by sanding the surface, cleaning with water and re-applying SILCOR® Top Coat 70 to a clean and dry surface
  • Re-coating of SILCOR® Top Coat 70 may be required over time based on its use and exposure


SILCOR® Top Coat 70 1 gallon unit
Available in the following standard colors: Grey

Technical Approval

Coating Type Two-component aliphatic urethane
Shelf Life 12 months
Recommended Thickness 5 mils wet film thickness per coat. Not to exceed 10 mils wet film thickness per coat.
Pot Life 3 hours at 70°F (50% RH)
Working Time 3 hours at 70°F (50% RH)
Tack Free Time 1 1/2 hours at 70°F (50% RH)
Pedestrian Trafficable 24 hours at 70°F

All declared values shown in this data sheet are based on test results determined under laboratory conditions and with the product sample taken directly from stock in its original packing without any alteration or modification of its component parts.

Cleaning and maintenance

  • Mixing and application equipment should be cleaned immediately with xylene. All solvents should be used only in accordance with manufacturer’s recommendations.
  • Do not use solvents to clean hands or skin.


Anticipated coverage of 300 ft2/gal per coat at 5 mil thickness. (Requires two coats; will yield approximately 150 ft2/kit). Coverage will vary depending on the profile of the surface.


SILCOR® Top Coat 70 should be stored in its original packaging. Protect from heat, sources of ignition, moisture, frost and direct sunlight. Storage temperature: 45ºF to 90ºF. Avoid opened containers, as moisture will cure the material. If not immediately applied after mixing, keep lid on pail to achieve maximum pot life. 


Do not apply when temperature is expected to fall below 35ºF overnight.

Health and Safety

Read and understand the product label and safety data sheet (SDS) for each system component. All users should acquaint themselves with this information prior to working with the products and follow the precautionary statements.

SDSs can be obtained by contacting your local GCP representative or office, by calling GCP toll free at 1-866-333-3SBM (3726) and in some cases from our website at | North America Customer Service: +1 (877) 423 6491

We hope the information here will be helpful. It is based on data and knowledge considered to be true and accurate, and is offered for consideration, investigation and verification by the user, but we do not warrant the results to be obtained. Please read all statements, recommendations, and suggestions in conjunction with our conditions of sale, which apply to all goods supplied by us. No statement, recommendation, or suggestion is intended for any use that would infringe any patent, copyright, or other third party right. 

SILCOR is a registered trademark, which may be registered in the United States and/or other countries, of GCP Applied Technologies Inc. This trademark list has been compiled using available published information as of the publication date and may not accurately reflect current trademark ownership or status. 

© Copyright 2018 GCP Applied Technologies Inc. All rights reserved.

GCP Applied Technologies Inc., 2325 Lakeview Parkway, Suite 475, Alpharetta, GA 30009, USA
GCP Canada, Inc., 294 Clements Road, West, Ajax, Ontario, Canada L1S 3C6
This document is only current as of the last updated date stated below and is valid only for use in the United States. It is important that you always refer to the currently available information at the URL below to provide the most current product information at the time of use. Additional literature such as Contractor Manuals, Technical Bulletins, Detail Drawings and detailing recommendations and other relevant documents are also available on Information found on other websites must not be relied upon, as they may not be up-to-date or applicable to the conditions in your location and we do not accept any responsibility for their content. If there are any conflicts or if you need more information, please contact GCP Customer Service.

Last Updated: 2024-06-21