In-form surface retarder

Product Description

PIERI® DURO-TARD™ is an in-form surface retarder for the most difficult of applications having a placement time of up to 90+ minutes. Abrasion resistance for vertical pours up to 12 feet. Heat resistance up to 150°F (65°C), a coverage rate 250-300 ft2/gal (6.1-7.4 m2/L). Available in nine depths of etch, each color and number coded. A test panel is recommended to simulating job conditions should be poured for proper grade selection.

Area of Application

Excellent for large or intricate (lengthy placement) architectural precast or for high vertical poured-in-place concrete (e.g. bridge work). For use with steel, concrete or plywood forms. Note that plywood forms should be sealed before use (PIERI® 245 Form Seal™).


For architectural precast (optional for poured-in-place), apply preparation coat of PIERI® VMR with brush or roller at a rate of 400–500 ft2/gal (9.8-12.3m2L). Allow to dry thoroughly, usually 10–15 minutes depending on temperature, humidity and ventilation.

Thoroughly mix PIERI® DURO-TARD™ surface retarder before using and apply a single coat (or two light coats) using brush, roller or airless sprayer at a total rate of 250-300 ft2/gal (6.1-7.4 m2/L); coat thickness (3–4 mils). Clean up with Xylene. Allow retarder to dry thoroughly, usually 20–30 minutes, before pouring concrete. Wash off at the end of the curing cycle with high-pressure water.

Caution: When steam curing, bring the temperature up gradually (not to exceed 150°F) to allow the surface retarder to react properly with concrete. Note: If steam is to be used, it should also be used with the test panel to ensure proper grade selection.

Technical Data

  • Solvent based
  • Flash point: 40°F (4°C)
  • Heat resistance: 150°F (65°C)

Shelf Life and Storage

Two years from manufacturing date when stored in closed original container.


Five gallon pails.


Product is highly flammable. Refer to SDS (Safety Data Sheet) prior to use. Keep away from heat, sparks and open flame. Keep away from children. Wear appropriate chemical resistant apron, gloves and other impervious protective gear; ear; use goggles/face shield. Use respirator for spray application.

Shipping Classification

Flammable Liquids NOS contains solvent naphtha (petroleum), light aliphatic, methanol (Methyl Alcohol), 3, UN1993, PG: II, Flammable Liquid.