Backerseal®

Secondary sealant to liquid sealants for joints in walls

A joint sealant for building walls and wall systems, Backerseal is an economical, precompressed, secondary joint sealant to field-applied caulking. Backerseal is a polyurethane foam infused with a hydrophobic-acrylic impregnation impregnation technology.

Unlike ‘double caulk and backer rod’, Backerseal behind field-applied liquid sealants provides true “belt and suspenders” sealing–two systems working on different principles to perform the same function. ‘Double caulk and backer rod’ is very difficult to install to achieve the geometry necessary to function in moving joints. In addition, the same forces (tensile stresses at the bondline and within the cured sealant) that will cause the outer installation to fail, will also likely cause the inner installation to fail as well. Backerseal works in compression providing a practical-to-install, fully functional secondary joint sealant using different performance principles than the primary, liquid sealant.  In addition Backerseal provides insulation and sound attenuation value as well as the ability to resist the effects of air-pressure differentials.

Backerseal®

Secondary sealant to liquid sealants for joints in walls

Features

  • Provides watertight secondary seal
  • Provides R-value at joints
  • Resists air pressure  differentials/ABAA compliant
  • Remains firmly in compression against substrates
  • Contributes to LEED
  • Odorless
  • Sound Attenuating
  • Clean handling
  • Non-staining
  • UV stable
  • Low temperature flexible
  • High-temperature stable

Sizes

Standard sizes | 1/4″ (6mm) to 1 1/4″ (30mm).
Custom sizes | 1/8″ (3mm) to 6″ (150mm).

Movement

+25%, -25% (50% total) of nominal material size.

Color

Gray

Uses

As a secondary sealant behind:

  • Conventional backer-rod and liquid sealants
  • Behind directly-applied liquid sealant

Ideally suited to:

  • panelized wall systems
  • curtain wall systems
  • window perimeters
  • precast panels
  • concrete
  • brick
  • stone
  • metal panels, etc.

(Note: Backerseal was formerly named GreyflexTM and may still appear in legacy specifications that way.)

Watertight—the tensionless silicone bellows is installed just below the deck surface. This ensures watertightness is achieved at the deck surface.

Non-Invasive Anchoring—there are no hard metal-to-concrete connections in the system. This includes embedded pins, anchors, screws, bolts or tracks, trays or rails. The system is locked to the joint faces by means of the 1) backpressure of the foam, 2) the epoxy adhesive, and 3) the injected silicone sealant band at the joint face to foam and silicone bellows interface.

Continuity of Seal—as in all EMSEAL expansion joint systems, continuity of seal through changes in plane and direction is an essential performance differentiator. Details for watertight, field-fabricated transitions from deck to wall, at curbs, sidewalks, parapets, tees, and crosses are available with the DSM SYSTEM.

Aesthetics & Versatility—Standard color is gray (other colors available), uniform bellows appearance, double sealing, fuel resistance, and an enhanced ability to handle variations in joint size are among other system features.

  • Produced by infusing a cellular foam base material with a hydrophobic, microsphere-modified acrylic impregnation, and coating the surface with a high-performance silicone to suit the application.
  • The external silicone facing is factory applied to the foam at a width greater than maximum joint extension and is cured before final compression.
  • Silicone application and curing takes place in a temperature and humidity-controlled factory environment. This ensures, in contrast to field applied liquid sealant and backer rod installations, that no movement takes place during curing that can cause deformation or stresses in the sealant material.
  • The material is precompressed to less than the joint size for easy insertion.
  • When compressed, a bellows is created in the coating. As joint movement occurs the bellows simply folds and unfolds free of tension on the bond line, and virtually free of tensile stresses in the silicone material.
  • The material is supplied in 6.56 LF (2m) shrink-wrapped lengths (sticks). After removal from the shrink-wrap and hard board restraining packaging, it expands gradually.
  • The foam provides a resilient backing to the silicone coating, making the system capable of resisting reasonable transient point loads.
  • Substrates must be parallel, plumb, have sufficient clear depth to receive the material specified, and be capable of resisting approx. 2.5 psi backpressure from the foam.
  • Fuel Resistance: Silicone sealant is not degraded by contact with fuel. Some swelling of the material will normally occur, but it will return to its original shape upon evaporation of the fuel.

Universal-90’s
(US Patent 9,200,437; Patent Pending)

  • Universal-90’s (or U-90’s) are factory-made 90-degree transition pieces that ensure continuity-of-seal where expansion joints change plane.
  • Use of U-90’s eliminates the field work needed to make plane changes making overall installation fast and efficient.
  • Watertightness through the plane change is guaranteed–leaving nothing to chance in field-fabricating inside and outside transitions.
  • U-90 transitions are symmetrically coated on both faces allowing them to be installed as an inside corner or as an outside corner.
  • Straight-run sticks are joined in the field to the U-90’s.
  • U-90’s have a 12-inch (305mm) long leg and a 6-inch (152mm) vertical piece on each side of the elbow.

Custom-90’s
(Patent Pending)

  • Custom-90’s, are factory-fabricated inside and outside 90-degree transition pieces coated on just the weather-facing faces.
  • Custom-90’s are available when field conditions and measurements are known up front.
  • Custom-90’s are widely used in stadium tread and riser applications or other applications where numerous inside and outside 90-degree transitions are required. Consult EMSEAL.

(More on Universal-90’s)

  • As with any construction product, the useful life of the material can be maximized with routine inspection and repair if required.
  • Clearing of surface debris and inspection will reveal any damage to the product or adjacent substrates that might affect building performance.
  • EMSEAL precompressed sealants are easily repaired–requiring only damaged sections to be removed and reinstalled–not the entire length of the joint as is typical of extruded-seal systems.
  • Available for shipment internationally.
  • Prices are available from local distributors or representatives and/or directly from the manufacturer.
  • The product range is continually being updated, and accordingly EMSEAL® reserves the right to modify or withdraw any product without prior notice.

Performance Testing:
Water penetration: ASTM E-331
Wind Loading: ASTM E330
Air permeability: ASTM E283-04
STC Rating: ASTM E90-09
OITC Rating: ASTM E90-09
R-Value: ASTM C518-04
Temperature Stability, Bleeding, Staining & Recovery