Radiant floor heating is categorized into two distinct groups: "wet" and "dry" systems. It has only been until more recently that dry systems have been used predominantly in homes over wet systems. Wet systems consist of running cross-linked polyethylene (PEX) tubing through concrete slabs which form the basis of the flooring. Thick concrete slabs are typically used in ranch style homes without basements. However, as heating technology improves, a newer hybrid material consisting of gypsum and concrete (called “Gypcrete”) is seeing more use. Gypcrete is lighter and thinner than standard concrete, and therefore can be used in homes with basements in which it does not have to provide structural support. The main difference between using thick slabs or Gypcrete is differing heat capacities, as well as the ability to maintain a constant temperature level. Thick concrete slabs have a much higher heat capacity than Gypcrete, however these slabs take longer to heat up than the latter option.
These wet radiant heating systems are seeing less use in modern homes as technology improves. Dry systems are becoming the norm because of their increased benefits. Not only are they easier and quicker to install in certain situations, they are more cost-effective as well. Such systems involve attaching PEX tubing to the underside of subflooring or embedding the tubing inside a subfloor much like the way a wet system is installed. The benefit in this is that the heat source radiates much more freely throughout the flooring. The main difference between suspending the tubing under the subfloor and embedding it directly into the floor is the amount of material used. Suspended tubing requires insulation beneath it in order to prevent heat loss. Embedded tubing does not require such insulation and therefore is considered to be a cheaper option. However, embedded tubing is a relatively new development and many manufacturers may not carry such flooring. Dry systems have become the ideal method in installing radiant heated flooring in home remodeling projects as well as new construction because of these advantages.
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