A.

1. Polyurethane and Polyurea is the next generation of coating in advancement of bitumen liquid
membranes.
2. Polyurethane is a combination of a Polyol and an Isocyanate hardener.
3. Polyurea combination of a Polyether Amine and an Isocyanate hardener this makes it a much more moisture
tolerant product.
4. Polyurethane and Polyurea unique properties give it the strength of the highest quality plastics but with the
flexibility of rubber.
5. Polyurethane and Polyurea is designed and certified to surpass the design life of most structures.

A.

1. Both spray applied or handy applied systems.
2. Fast set and rapid cure and each has its own place with Unique characteristics.
3. Although in some cases there are lap overs into the same market segments.
4. Polyurethane presents the best compromise between costs and quality.
5. Polyurea can be used in extreme conditions Gels in 5–12 Seconds, Tack free in 30–60 seconds.
6. Very high physical properties making a hard wearing durable coating, moisture insensitive.
7. Wide range of service temperatures from -30c to +150c.
8. Good abrasion and chemical resistance, yet remains fully flexible.

A.

Waterproofing is the combination of materials or systems that prevents water intrusion into structural elements of a building or its finished spaces. Basic waterproofing and envelope design incorporates three steps to ensure a watertight and environmentally sound interior:

1. Understanding water sources likely to be encountered.
2. Designing systems to prevent leakage from these sources.
3. Finalizing the design by properly detailing each individual envelope component into adjacent components.

A.

Each separate envelope trade contractor’s work, regardless of its being thought of as a waterproofing system or not, must become part of a totally watertight building envelope. Equally important, all individual envelope systems must be adequately transitioned into other components or provided with watertight terminations. The resulting improper attention to details is responsible for countless problems in construction.

90 percent of all water intrusion problems occur within 1 percent of the total building or structure exterior surface area. This 1 percent of a building’s exterior skin area contains the termination and transition detailing.

A.

Water present at below-grade surfaces is available from two sources-surface water and groundwater. Beyond selection and installation of proper waterproofing materials, all waterproof installations must include methods for control and drainage of both surfaces and groundwater.

A.

Shore hardness is resistance to impact, measured by a durometer gage. This property becomes important in choosing sealants subject to punctures or traffic, such as horizontal paver joints. A hardness of 25 is similar to a soft eraser; a hardness of 90 is equivalent to a rubber mallet.

A.

Of the many problems that might occur in sealing joints in temperatures below freezing, the most serious is joint contamination by ice. In freezing temperatures, a joint surface can be covered with ice that is not visibly noticeable but that will cause the sealant not to bond to the substrate. Even if the sealant is warmed sufficiently to melt this ice, the resulting joint wetness will cause failure. Therefore in freezing temperatures it is critical that joints be heated and dried before sealant application.