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W. R. MEADOWS has developed a low-temperature version of PRECON for applications below 40° F (5° C), PRECON WINTER-GRADE. The minimum ambient and substrate temperature for PRECON WINTER-GRADE is 20° F (-7° C) and rising.
PRECON WINTER-GRADE and any accessory products must be stored in their original, unopened packaging at temperatures above 40° F (5° C). For optimal performance, store materials at 60° F (16° C) or above until just prior to application.
Installation of PRECON WINTER-GRADE should not occur in the presence of dew, rain, snow or ice, or if there is any ponded water because of melting frost, ice or snow. The presence of water or moisture on the membrane surface during its installation will prevent the proper adhesion of the overlap seams. The membrane must be dry and avoid surface moisture.
Certain environmental conditions may cause the formation of dew on the plasmatic core (black film), which could impede the bond at the selvage edge. This may occur at temperatures above or below 60° F (16° C) and will necessitate the use of MEL-PRIME™ (solvent-based versions) on the selvage edge to ensure a water-tight bond at the seams.
Concrete placement should be completed within 60 days of the installation of the PRECON WINTER-GRADE and it is recommended it be done as soon as possible to prevent damage to the membrane. After installation, the membrane should be protected from damage.
During installation of PRECON WINTER-GRADE at lower temperatures and under certain environmental conditions, additional steps in the installation need to be followed to ensure that proper adhesion of the joints and overlap seams is obtained.
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For optimal watertight performance, MEL-PRIME (solvent-based versions) should be used at all factory edge joints. MEL-PRIME is to be applied at a width of 6” (152.4 mm) and allowed to dry prior to overlap of the adjoining sheet of PRECON.
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Following this, all areas of this overlap need to be pressure rolled three times (back and forth) well to ensure for proper adhesion. Inadequate rolling will cause poor overlap adhesion.
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Dry time for MEL-PRIME (solvent-based) will vary from 30 mins to two hours depending on the ambient and substrate temperature. Dry time at 20° F (-7° C) is approximately 3.5 hours. Minimum application temperature is 20° F (-7° C) and rising. Do not apply MEL-PRIME (solvent-based) if rain is imminent. For optimum performance, HYDRALASTIC 836™ is to be used for all end lap details and terminations. The procedure is as follows:
a. Apply HYDRALASTIC 836 in the area to be lapped at a width of 3” (7.6 cm) and roll press the overlapping PRECON while still wet.
b. Apply HYDRALASTIC 836 at the termination of this overlapping sheet 12” (30 cm) wide centered over the termination.
c. While the HYDRALASTIC 836 is still wet, embed 12” (30 cm) wide strip of PRECON WINTER-GRADE and roll press into place. Then place DETAIL FABRIC from W. R. MEADOWS centered over the termination with 6″ (152.4 mm) on each side of lap edge.
d. Apply additional HYDRALASTIC 836 on all terminations of the DETAIL FABRIC.
4. Prior to placement of the concrete, ensure that the substrate is clean, dry and frost-free.
It is important to review each application as there may be situations that would require either of these procedures to be modified based on the project requirements. If there are any concerns during the installation, contact technical support for assistance.
2025-08