Gypsum concrete floor underlayment (i.e., Gyp-Crete®, FIRM-FILL® Gypsum Concrete, etc.) is used extensively in the construction of multi-family apartments and condominium buildings – with a reported installation exceeding four billion square feet. It is lighter than traditional concrete, which reduces the structural requirements, yet meets the noise control and fire building codes of many municipalities. Gypsum concrete is mixed on-site and pumped onto a structurally sound, broom-clean subfloor. It self-levels and fills the space where the drywall meets the floor, completely sealing room perimeters and protecting the base plates from the spread of fire. Gypsum concrete also reduces horizontal and vertical sound transmission. It sets up quickly and can be walked on after 90 minutes – allowing other light sub-trades to begin work the next day. Gypsum concrete is considered a “green” building material, and also meets the stringent volatile organic compound (VOC) requirements of GREENGUARD Gold Certification.
Overall, gypsum concrete provides a cost-effective means of providing fire and sound barriers, without impacting the project schedule. While it often appears to be the right product for the job, there have been numerous construction defect and product liability claims and losses related to its use. Water damage and mold have been reported on several construction projects using gypsum concrete – resulting in multi-million dollar losses and schedule delays.