Expansion Joints and Pre-Compressed Sealants
Watertight Joint System for Decks and
• Tensionless silicone bellows
• Traffic durable
• Rapid installation--new or retrofit
• Staged installation preserves traffic flow
• Joint-face adhered
• airport aprons
• mall bridge connectors
foundation/tunnel wall joints.
• perimeter joints
• For concrete substrates
• For metal substrates where demolition and removal of existing embedded
metal angles is not feasible or affordable.
• Lasting replacement of tee-to-tee caulk joints in precast-concrete
parking decks and
1/2" to 4"
(12 - 100mm)
Note: Sizes under 1 1/2"
are manufactured with a single bellows. Larger sizes incorporate multiple
bellows. (Above 4"
SJS SYSTEM or
Up to 100% Total (+50% and -50% of nominal supplied size)
(For joint openings 4-inches (100mm) and larger, where an integral coverplate is preferred, consider SJS SYSTEM)
Standard color is gray
(for other colors contact
The DSM SYSTEM builds on a track record of over 30 years of sealing
horizontal plane and below-grade expansion joints with impregnated foam
The system is comprised of:
1) Pre-compressed, silicone-and-impregnated-foam hybrid installed
2) field-applied epoxy adhesive on the joint faces; with the silicone
bellows locked to the joint faces with...
3) a silicone sealant band (see Figure 1).
The DSM SYSTEM features an innovation in sealant technology in the form
of a innovative, microsphere-modified acrylic adhesive infused into
the cellular foam base material.
DSM features sealing performance significantly greater than any
impregnated pre-compressed predecessor. In addition, it is odorless,
clean handling, UV stable, non-staining, and
low temperature flexibility not previously available in asphalt,
wax, or isobutylene-based predecessors.
The result is extension of the usability of the product to applications
where asphalt or wax-based predecessors did not work well under conditions
of thermal shock (rapid opening and closing of joints during large
temperature swings). These applications include joint-face adhered
installations on top decks as well as intermediate decks.
The DSM SYSTEM has an
extensive track record
of service throughout the world. It has been widely adopted as the
replacement for virtually all applications where older, inflated-type
systems were once favored. In contrast to the inflated seals, the DSM
SYSTEM remains in compression over its life. As a result it is not
subject to failure due to excessive tension on the bond line.
Watertight—the tensionless silicone bellows is installed just below the
deck surface. This ensures watertightness is achieved at the deck
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.
DSM SYSTEM in Typical Concrete Substrates:
DSM SYSTEM in Existing metal
• Substrates must be parallel, plumb and 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.
• DSM is produced by infusing a cellular foam base material
with EMSEAL’s microsphere-modified acrylic impregnation and is
coated with a highway-grade silicone. DSM-DS is also available which is built
with the silicone coating on the top and bottom surface.
• The silicone external facing is factory applied to the foam at a width
greater than maximum joint extension and is cured before final
• Silicone application and curing takes place in a factory-controlled
environment. In contrast to field applied liquid sealant and backer rod
installations, no movement takes place during curing that can cause
deformation or stresses in the material.
• 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
• The foam provides a resilient backing to the silicone coating, making
the system capable of resisting reasonable transient point loads.
• DSM SYSTEM is supplied in 6.56 LF (2m) shrink-wrapped lengths
(sticks). It is pre-compressed to less than the joint size for easy
insertion. After removal from the shrink-wrap and hard board restraining
packaging, it expands gradually.
Click here to see
who's using DSM?
Transitions and Terminations:
(US Patent 9,200,437 Patent Pending)
U-90's are factory-made transition pieces that ensure continuity-of-seal where expansion joints change plane or direction.
Custom-90's (patent pending), coated on just the weather-facing faces, are also available when field conditions and measurements are known up front.
DSM is manufactured in straight-run sticks which can be joined in the field to EMSEAL’s patented and patent-pending "Universal-90" transitions.
These factory-fabricated single-piece 90-degree units have a 12-inch long leg and a 6-inch vertical piece on each side of the elbow. Universal-90 transition are symmetrically coated on both faces allowing them to be installed as an inside corner or as an outside corner.
In addition to guaranteeing watertightness, EMSEAL’s "Universal-90's" allow for much faster and secure installation by eliminating field cutting or notching and bending, at angles.
(More on Universal-90's
Flipped-Over as Downturn Transition