Application and Function
Schluter-BEKOTEC is a lightweight modular screed system that is used to create continuous screed surfaces without control joints or reinforcement and is designed to accommodate hydronic radiant heating tubes. Since it is a floating system, the assembly can be customized to meet a range of heat and sound requirements.
9.1 Schluter-BEKOTEC and 9.2 Schluter-BEKOTEC-F are modular screed systems that produce permanent flooring assemblies that are free from internal stresses. The bases for these systems are the Schluter-BEKOTEC-EN/US/P and Schluter -BEKOTEC-EN23F studded polystyrene screed panels that are placed directly over any load-bearing substrate and optional common sound and/or heat-insulating layers. The studs effectively divide the screed into smaller, 4-1/4" (108 mm) square modules, thereby confining shrinkage and curing stresses to control deformations such as curling and continuous cracks that can be common in a traditional screed. These modular screed systems allow the installation of continuous screed surfaces without any control joints or wire reinforcement. The elimination of control joints allows surface movement joints to be placed to match the joint layout in the tile covering.
The cross-section of the assembly reveals a minimum screed thickness of 1-1/4" (32 mm) between the studs and 5/16" (8 mm) above the studs. This results in significant material and weight savings over traditional screeds. For example, a 1-1/4" (32 mm)-thick traditional mortar bed weighs approximately 15-lb/ft2 (0.72 kPa), while a BEKOTEC mortar screed weighs approximately 12 to 12.5-lb/ ft2 (0.57 - 0.60 kPa), representing a 15 - 20% decrease. Material and weight savings compared to a 2" (51 mm)-thick mortar bed amount to approximately 50%.
The studs form a grid pattern, with a distance of 3" (76 mm) between studs to accept hydronic heating tubes 3/8” (10 mm) to 5/8" (16 mm) O.D. if a heating screed is to be installed. Since the screed mass to be heated is relatively small, the floor heating can be well regulated and operated at a low temperature range. The modular screed system reduces impact sound transmission. Since it is a floating screed system, it is also possible to incorporate a variety of sound attenuation materials below the panel, allowing for even greater impact sound reduction.
Ceramic and stone tile is installed over the modular screed using the Schluter -DITRA or Schluter-DITRA-XL uncoupling membrane. Please refer to the Schluter- DITRA Installation Handbook (detail D-C-TS for Portland cement-based screeds and detail D-G-TS for gypsum-based screeds) for installation requirements, including but not limited to setting and grouting materials, setting and grouting specifications,and movement joint placement. Surface coverings not sensitive to cracking, such as parquet or carpet, can be placed directly over the screed as soon as the residual moisture has reached an appropriate level.