ZAR® Exterior Water-Based Polyurethane

ZAR® Exterior Water-Based Polyurethane

Formulated exclusively to deliver superior performance on exterior wood surfaces, ZAR® Exterior Water-Based Polyurethane contains ultraviolet radiation absorbers and antioxidants.

It is the ideal choice for surfaces that would benefit from a clear protective coating: siding, gables, and patio furniture, as well as steel and fiberglass entry doors.

ZAR® Exterior Water-Based Polyurethane Application

Quick Overview

Environmentally safe, ZAR® Exterior Water-Based Polyurethane is the perfect finish for surfaces exposed to direct sunlight and the harsh extremes of weather. The full-bodied formula brushes on like a conventional (oil-based) polyurethane for maximum durability and beauty.

  • Light amber finish
  • Recommended by leading door manufacturers
  • Excellent marine-grade finish
  • Soap and water cleanup

Product Features:

  • Finishes: Semi-Gloss, Gloss, Satin, Matte
  • Sizes: pint, quart, gallon
  • Coverage: 500-600 square feet per gallon
  • Application tools: foam brush, synthetic fiber brush
  • Dry time: 30 minutes to touch
  • Coats: 3
  • Recoat: 2-3 hours


  • Wood
  • Metal
  • Fiberglass


ZAR® Wood Finishing Project Guide



Exterior Surfaces of Stained Steel Doors and Fiberglass Doors
Stain must be thoroughly dry. Do not sand uncoated stained surfaces.

New Wood
Sand smooth using fine sandpaper and vacuum any sanding dust.* Wipe using a tack cloth to remove any remnants of dust prior to application. Do not use steel wool. If open-grained woods are to be filled, use a filler that does not contain stearates or waxes, such as ZAR® Wood Patch or ZAR® Trowelable Wood Patch.

Old Finishes in Good Condition
Remove grease, dirt, and wax.* Sand lightly in the direction of the grain to remove any gloss. Do not use steel wool. Vacuum all sanding dust. Wipe using a tack cloth to remove any remnants of dust prior to application. If the old finish contains wax or stearates, regardless of condition, remove it completely. Test ZAR® Exterior Water-Based Polyurethane in an inconspicuous area for compatibility.

Old Finishes in Poor Condition, Lacquer or Shellac
Remove it completely.* Do not use steel wool. Sand and vacuum all sanding dust. Wipe using a tack cloth to remove any remnants of dust prior to application.


Apply when air and surface temperatures are between 60°F and 90°F and the relative humidity is less than 50%. Stirring is not required for ZAR® Exterior Water-Based Polyurethane Gloss. For Satin and Semi-Gloss, stir thoroughly before and during application. Do not shake. Use a clean synthetic fiber or foam brush. Do not apply with a roller. To ensure satisfactory results, always test ZAR® Exterior Water-Based Polyurethane in an inconspicuous area before completing entire job. ZAR® Exterior Water-Based Polyurethane goes on milky from the can, but dries to a rich amber color. Apply thin coats at a rate of 500-600 square feet per gallon in the direction of the grain. Do not over brush or trap air bubbles in the finish. Sand lightly between coats (except fiberglass or grained surfaces) with a fine grit sandpaper. Remove all sanding dust with a vacuum or tack cloth. Apply 3 coats.

Note: when staining an exterior door with an interior wood stain, use a quality oil-based stain such as ZAR® Wood Stain or use an interior water-based stain. Allow oil-based stains to dry for a minimum of 48 hours. For water-based stains, follow manufacturer’s directions. Do not apply ZAR® Exterior Water-Based Polyurethane over paint.

Exterior durability depends on the amount of exposure to sun and weather conditions. Inspect the finish yearly for signs of wear. If minimal deterioration has occurred and no visible damage is detected, clean the surface thoroughly, sand lightly with fine sandpaper and apply another coat.


Dispose of contaminated absorbent, container and unused contents in accordance with local, state and federal regulations.

USAGE STATEMENT: Prior to use, carefully read the product label and follow the directions. For technical information, warnings, cautions, notices, and additional information, download and read the documentation available on this website.

* WARNING: If you scrape, sand or remove old paint, you may release lead dust. LEAD IS TOXIC. EXPOSURE TO LEAD DUST CAN CAUSE SERIOUS ILLNESS, SUCH AS BRAIN DAMAGE, ESPECIALLY IN CHILDREN. PREGNANT WOMEN SHOULD ALSO AVOID EXPOSURE. Wear a NIOSH-approved respirator to control lead exposure. Clean up carefully with a HEPA vacuum and a wet mop. Before you start, find out how to protect yourself and your family by contacting the National Lead Information Hotline at 1-800-424-LEAD or visit