Question 3: What is the minimum thickness of Gypcrete that can be installed over the following types of subfloors, Radiant Tubing, Acoustical Mat (Acousti-Mat), Plywood, Concrete or over the top of Marino/Ware and Dietrich Steel Decking?
Answer 3: I will answer this question with a short explaination. Floor Deflection has a large impact on the depth that is required at a minimum. However the standard rule of thumb applies in 95% of case's.
Radiant Tubing - Minimum amount above the tubes is 3/4"
Acousti-Mat CLP - Requires 1/2" topping
Acousti-Mat 2 - Requires 1" of topping
Enkasonic - Requires 1.5" of topping no reinforcement
Acousti-Mat 3 - Requires 1.5" topping plus reinforcement or 2" with no reinforcement
ACM CSD (Corregated Steel Deck) Mat - Requires 1.5" topping no reinforcement
Marino / Ware and Dietrich Corregated steel decking - Requires 1" above the high point
3/4" T & G Plywood Subfloor require 3/4" minimum of topping
Concrete Slab or Precast Concrete - Requires to maintain a minimum of 3/8" but may be featheredge at the high point or door ways.
Question 4: Should I use Gypcrete (Therma-Floor) for my radiant heat system or a Mud Job Installation?
Answer 4: I will give you the facts so you come to your own conclusion.
1. Thermal Mass - Both Gypcrete (Therma-Floor) & a Mud Job have high thermal mass however because Therma-Floor is mixed in a wet form it doesn't have the air voids that are found in Mud Jobs thus resulting in better transfer of heat.
2. Reinforcement - Gypcrete (Therma-Floor) does not require reinforcement unless a moisture barrier has been applied that impedes bond. Mud Jobs always require a moisture barrier and wire reinforcement because they are mashed into place and have not enough water to make a bond to it self let alone to the subfloor.
3. Installation - Because the materials are mixed and pumped in, Gypcrete type products will use less man power and a fraction of the time to install. Mud Job Requires mixing Portland and sand together with little water then since it is not pumpable it must be man handled to the area that is to be installed thus shutting down your project for extended periods of time instead of the single day typical of Gypcrete Installs.
