UsageVersatile primer for use with Sikalastic®-500 RoofCoat Systems Suitable for use on:
- Polyurethane Elastomeric Surfaces
- Substrate Penetrating
- Low Viscosity
- Quick Cure/Re-coat Time
2 gal. (7.6 L) kit and 10 gal. (37.8 L) kit
Part A: 1 gal. (3.8 L), 5 gal. (18.9 L) Part B: 1 gal. (3.8 L), 5 gal. (18.9 L)
Part A: Black Part B: White
Two component epoxy
12 months in unopened container
Keep containers closed and store in a dry, cool place away from direct sunlight, heat, sparks, open flame, and moisture. Keep material stored above 65 °F (18 °C). Open containers should be blanketed with dry nitrogen before resealing.
Part A: 1.30 kg/l Part B: 1.89 kg/l
90 % by weight
84 % by volume
Volatile organic compound (VOC) content
Part A : Part B = 1:1 (by volume)
Ambient Air Temperature
41 °F (5 °C) min. / 104 °F (40 °C) max.
Relative Air Humidity
80 % R.H. max.
Beware of condensation. The substrate and uncured coating must be ≥ 5 °F (3 °C) above dew point.
41 °F (5 °C) min. / 140 °F (60 °C) max.
Substrate Moisture Content
≤ 4 % moisture content Test method: Sika®-Tramex meter No rising moisture according to ASTM (Polyethylene-sheet).
60–90 minutes (at 75 °F (24 °C) and 50 % R.H.)
Waiting / Recoat Times
Allow primer to cure completely prior to applying membrane resin. Full cure: 4 hours at 68°F. Ideally, membrane resin will be applied within 24 hours of primer application. Maximum primer exposure is 48 hours. Primer exposed longer than 48 hours, and primer exposed to water during curing and exhibiting a chalky appearance, must be reprimed. Deteriorated primer must be mechanically removed before primer reapplication.
1 gal/300 sq. ft. on non-absorbent smooth substrates. 1 gal/200 sq. ft. on prepared dry concrete. Note: Rough, porous, or absorbent surfaces will require additional primer and will reduce yield.
Sikalastic®-502 Primer should not be diluted under any circumstance. The volume mixing ratio: 1 Part B white liquid to 1 Part A black liquid. Premix Part A and part B components separately using low speed (400–600 rpm) mechanical mixer and Jiffy paddle at slow speed to obtain uniform color (typically 30 sec), making sure to scrape the solids from the bottom and the sides of the pail. Add Part B to Part A pail. Mix the combined material thoroughly until a homogenous mixture and uniform color is obtained (typically 3 min.)
Remove all contaminants, oil and grease from substrate. Sikalastic®-502 Primer should be applied at the rate of 1 gal. (3.8 L) (mixture of part-A & part- B)/200–300 ft2 (18.6–27.9 m). It can be applied using an airless sprayer, brush, or phenolic resin core roller. Allow Sikalastic®-502 Primer to become tack free before applying the coating. If Sikalastic®-502 Primer is allowed to dry completely, re-prime the surface before proceeding. Sikalastic®-502 Primer is sensitive to heat and moisture. Higher temperatures and/ or high humidity will significantly accelerate the cure time and decrease pot life. Use caution in batch sizes and thickness of application. Low temperature and/or low humidity extend the cure time.