UraSeal 210 is a two component polyurethane sealant specifically designed to seal against water in concrete joints or as a coating over concrete or wood. UraSeal 210 performs exceptionally well in horizontal joint or spalled edges where excellent adhesion, high resiliency, and weather resistance are needed. In addition, it has a moderate penetration and structure resistance combined with exceptional elongation. UraSeal 210 offers exceptional economics for numerous sealant applications. All surfaces must be primed with Primer 200, and free of dirt, dust and grease to achieve optimum adhesion. UraSeal 210 is especially designed for use in exterior horizontal deck and surface joints in and between masonry. It is well suited for a wide variety of environments subject to sunlight, water immersion and attack from most chemicals or industrial pollutants. It is especially recommended for joints in airport runways, highways, bridges, plazas and industrial concrete floors. Optimum performance can also be expected when UraSeal 210 is applied to terraces and patios, roof gardens, driveways and loading docks, stadiums and other exterior facilities exposed to pedestrian or vehicular traffic. When used on steel, surface must be cleaned to bright metal and primed with Primer 200. Not for use on surface having a high crown or marked degree of slope. Do not apply over asphalt impregnated joint fillers. Painting is not recommended. When subjected to water immersion conditions primer must be used. When UraSeal 210 is used as a roofing product, Primer 200 should be used to enhance surface adhesion along with Plexkote acrylic topcoat.

Application and Mix Ratio

Component A and component B as supplied do not require premixing.
Carefully measure out Component A (100 parts) to Component B (96 parts) by Weight or 1:1 by Volume.

Joint Design: To a large extent, the design of the joint depends upon a variety of factors such as the maximum expansion and contraction of the surface materials due to thermal change. Where possible, UraSeal 210 should be applied when the joint is at its median opening so as to obtain the greatest efficiency with subsequent joint movement. The dimensions of the joint to be sealed must be established in relation to service conditions. The number of joints and joint width should be designed not to exceed +-25% maximum movement. The joint width may be determined by calculating the change in size of the joint between the high and low temperature extremes, multiplying the change by a factor or 4. For example, if it is determined that a joint width should be four times the ¼" or 1" minimum, the depth of the sealant should be ¾ the width of the joint (see table below).

Joint Width Inches

Sealant Depth at Midpoint Inches

½" to 1"

3/8" to ¾"

1" to 2"

¾" to 1 ½"


Where the joint design creates a joint deeper than the maximum indicated, the sealant depth should be controlled by backer-rod as indicated below. Backer-rod: For light traffic conditions, backer-rod is recommended. Closed Cell polyurethane foams and fillers are also satisfactory. Avoid using sand, asphalt-impregnated fillers or natural fibers such as jute. For joints subject to puncture by high heels, umbrella points, etc., a stiffer or higher density back up material is preferred. Cork or rigid cane fiber fillers (non-asphalt impregnated) are suitable. Care should be taken that backer-rods or joint fillers are tight to the sides of the joint to prevent sealant loss through the bottom. Do not use other caulks as a bottom bed in a joint. For optimum results, joint sides must be structurally sound, clean, dry and free of all loose aggregate, paint, oil, grease, wax, mastic compounds, water proofing compounds and form release agents. Do not apply sealant if bed beneath deck or substrate has become saturated with water due to rain, construction activities or other causes. Excess ground moisture can cause sealant failure. If such a condition exists, allow sufficient time for ground to dry, and then apply sealant. On concrete, remove all loose material by wire brushing. Sandblast surfaces that have been in contact with form release agents. Fresh concrete must be fully cured at least 7 days. Latinate must be removed by abrading. For old concrete, remove all old joint sealing material by mechanical means. If joint sides have absorbed oils, sufficient concrete must be cut away to assure clean surface. Prime steel in contact with UraSeal 210 with Primer 200 after cleaning to bright metal. For water immersion, prime with Primer 200. Apply the primer in a thin, uniform coat by brush. Allow approximately 30 minutes drying time before applying sealant. UraSeal 210 can be poured from a can or applied by a gun. Fill joint from bottom to prevent formation of air voids. Sealant will self-level to form a clean joint bead. Application at extremely low temperature should be avoided because of possible moisture condensation and because the viscosity (thickness) of the sealant increases as the temperature decreases. If humidity is very low, initial cure may have a slight tack; but tackiness will soon disappear. Protect from traffic until fully cured.


Working Properties

Mix Ratio By Weight

100 parts A/ 96 part B

Mix Ratio By Volume

100 parts A/ 100 parts B

Viscosity @ 72°F (A Side)

2500 CPS

Viscosity @ 72°F (B Side)

800 CPS

Viscosity @ 72°F (Mixed)

1500 CPS


Part A:



Part B:

Off White



Light Gray

Working Life @ 72°F

15 minutes

Set Time* @72°F

24 hours

* Set time and Demold time depends on temperature and relative humidity.


Physical Properties

Specific Gravity (Part A)


Specific Gravity (Part B)


Specific Gravity (Mixed)


Weight/Gallon Part A

9.15 lbs.

Weight/Gallon Part B

8.83 lbs.

Weight/Gallon Mixed

9.00 lbs.

Hardness @ 72° F

ASTM 2240-85

25-35 Shore A

Tear Strength

ASTM D-624

139 lb./in.

Tensile Strength

ASTM D-412 die C

604 psi


ASTM D-412 die C


Ultimate load

ASTM D-412 die C

14.64 lbs.

Modulus (100%)


85.5 psi

Modulus (300%)


216 psi


Clean Up

Dispose of all empty UraSeal 210 component containers in accordance with local, state and federal regulations. Empty component containers can be rendered non-hazardous by rinsing the containers with a small amount of mixed material and allowing material to cure for 24 hours. The containers will then contain non-hazardous cured urethane.

Storage and Shelf Life

UraSeal 210 is shipped from the factory in sealed containers. The containers should be stored in a cool, dry area that is protected from direct sunlight and moisture. Storage temperatures should not exceed 80°F. The shelf life of factory sealed containers stored under these conditions is six months. Containers that have been opened should be resealed immediately after material has been removed in order to prevent solvent evaporation.


Shipping Class: Class 55 Non-hazardous