AIR-SHIELD LSR – Air/Vapor and Liquid Moisture Barrier

Liquid Membrane Air/Vapor and Liquid Moisture Barrier

AIR-SHIELD LSR (liquid synthetic rubber) is an asphalt-free, single-component, synthetic rubber based liquid air/vapor and liquid moisture barrier. AIR-SHIELD LSR cures to form a tough, seamless, elastomeric membrane, which exhibits excellent resistance to air and moisture transmission.

AIR-SHIELD LSR has been specifically formulated to act as an air/vapor and liquid moisture barrier within the building envelope.  It may be applied to most common surfaces and integrated into various wall systems.  AIR-SHIELD LSR is suitable for both new construction and restoration.


  • Non-asphaltic – designed to meet stringent fire code requirements.
  • Low permeability – prevents the transmission of air and inhibits moisture and vapor from passing through porous building materials.
  • Highly flexible – bridges cracks, which may form in the substrate.
  • Environmentally compatible – AIR-SHIELD LSR is non-toxic.
  • User friendly – single-component, water-based technology allows for simple, safe application and easy cleanup.
  • Liquid applied – simplifies detailing and assures a monolithic, seamless membrane when applied to a rough or smooth surface.
  • Sprayable – with appropriately configured airless spray equipment – low application costs.
  • Excellent adhesion – remains firmly bonded to the substrate, even when applied over damp
  • Low VOC content (<100 g/L). Produces no harmful odors.
  • Compatible with asphalt-based emulsion products.
  • UV resistant – membrane can be left exposed up to four months.

5 Gallon (18.93 L) Pails
55 Gallon (208.20 L) Drums

Application Rate
17 – 22 ft.2/gal.
(1.59 – 2.05 m2/3.8 L)
Wet Film Thickness
75 mils
Cured Film Thickness
40 mils (1 mm)
Coverage dependant on substrate type, weather, and application conditions.

When stored indoors in original, unopened containers at temperatures between 40° – 90° F (4° – 32° C), optimum performance and best use is obtained within one year of date of  manufacture.


  • ASTM E 84, Class A
  • Exceeds ABAA maximum material air permeance requirements when tested in accordance with ASTM E2178.
  • Complies with all current federal, state, and local maximum allowable VOC requirements, including U.S. EPA, LADCO, SCAQMD, and OTC.
Category: Brands: .


Solids Content, %: 56
VOC Content, g/L 56
Color: Sprays Pink
Dries to Desert Tan
Flexibility @ -26° C (-15° F), PASS
(ASTM C 836):
Tensile Strength (ASTM D 412), PSI 250
Elongation (ASTM D 412), %: 700
Water Vapor Permeance 0.1
(ASTM E 96, Procedure B) Perms:
Service Temperature: Not to exceed 175° F
(80° C)
Nail Sealability (ASTM D 1970): Pass
Storage Temperature
40° – 90° F  (4° – 32° C)
Air/Substrate Temperature
(At Time of Application):
>20° F (-6.7° C)

Air Leakage

Test Method ASTM E 2178-01 ASTM E 2357
Pressure: 75 Pa (1.57 lb/ft.2) 75 Pa (1.57 lb/ft.²)
ABAA Requirements, maximum: 0.004 cfm/ft.2
(0.02 L/S/M2)
0.04 cfm/ft.²
(0.2 L/S/M²)
AIR-SHIELD LSR Results: <0.004 cfm/ft.2
(<0.02 L/S/M2)
<0.04 cfm/ft.²
(<0.2 L/S/M²)

*Independent test available upon request

AIR-SHIELD LSR may be used in NFPA 285 complying wall assemblies.  Contact W. R. MEADOWS for further information.

Surface Preparation … All surfaces must be clean (free of all coatings and curing compounds), structurally sound, frost-free, and relatively smooth.  Prepare substrate per manufacturer’s instruction prior to application of membrane.

Exterior Sheathing Panels … Exterior sheathing panels are to be installed and fastened per manufacturer’s recommendation. For detailed application information, see INSTALLATION INSTRUCTIONS: JOINT TREATMENT OF EXTERIOR SHEATHING PANELS.

Rough Openings and Protrusions … Refer to AIR-SHIELD ROUGH OPENINGS INSTALLATION GUIDELINES document for recommendations on protrusions and rough openings.

Concrete Masonry Units … Before applying AIR-SHIELD LSR to CMU surfaces, patch all cracks, protrusions, small voids, offsets, details, irregularities, and small deformities with MEADOW-PATCH® 5 or MEADOW-PATCH 20 from W. R. MEADOWS at least two hours before application.

Application Method … AIR-SHIELD LSR may be applied by spraying or a 3/4″ (19.1 mm) minimum nap roller. (For recommendations on spray equipment, consult W. R. MEADOWS technical staff.)

AIR-SHIELD LSR may be sprayed on at the minimum coverage rate of approximately 17 – 22 ft.2/gal. (0.42 – 0.54 m2/L) (75 mils wet) (40 mils dry). Note: For roller applications or during periods of extremely hot weather, two coats may be necessary if the material begins to slump. Apply second coat after first coat has completely dried, approximately one to two hours after first coat. Frequently inspect surface area with a wet mil gauge to ensure consistent thickness. Work material well into any fluted rib forming indentations. Porous masonry block walls may require additional coats to obtain desired thickness.

Curing and Drying … Allow material to dry at air and surface temperatures of 20° F (-6.7° C) or higher. Curing times will be affected by relative humidity, temperature and airflow.  The following times are given for average conditions

and standard thicknesses. Actual times may differ, depending on specific conditions present on job at time of application. It is recommended that AIR-SHIELD LSR be allowed to air dry to a tack-free film before application of specified insulation. Maximum exposure time for AIR-SHIELD LSR is four months.

Tack-free film: 2 hours
Full cure: 48 hours

Cleanup … Uncured AIR-SHIELD LSR cleans up easily while wet with water. Cured material is best removed by xylene or by mechanical means.

AIR-SHIELD LSR is not designed to perform as a permanently exposed membrane. Maximum UV exposure period for membrane is four months.  Keep containers tightly sealed. KEEP FROM FREEZING.  Do not apply AIR-SHIELD LSR if rainfall or snow is forecast within 12 hours.

Please contact W. R. MEADOWS for specific details and/or data not outlined in this literature.  Technical assistance, from design to product application, is available upon request.

May help contribute to LEED credits:

  • EA Credit 1: Optimize Energy Performance
  • IEQ Credit 3.1: Construction Indoor Air Quality Management Plan – During Construction
  • IEQ Credit 7.1: Thermal Comfort – Design
  • MR Credit 2: Construction Waste Management
  • MR Credit 5: Regional Materials

This material last updated May 2015.