Radiant Heat Pipe Basics

The installation of a radiant heat pipe is necessary if you wish to incorporate radiant floor heating in your home. Other types of radiant heat include ceiling and wall panels, which are quite different than radiant floors, although the physics of heat generation is the same. Radiant heating is a more efficient means of heating the home than baseboard or forced air heating. Due to the fact that these systems use ducts through which the heated air must travel, heat is lost before it gets to a room. Radiant floor heating is a more efficient way of warming a home since it loses very little heat during the transition from boiler to individual room radiator. There are variations in the way that radiant floor heating systems are installed and in the piping used to transfer the heated water. In order to understand how a hydronic radiant floor heating system works, further clarification is required. 

Radiant Floor Installation 

The two methods for installing radiant heat in the floors are known as “wet” and “dry” installations. Both involve a series of pipes or tubes running below the floor level. However as the pipes produce heat, the heat rises into and warms the rooms. Wet installations involve laying pipes directly into a concrete slab situated below the floor. The pipe can either be fixed in a thick thermal slab of concrete or a thinner layer that is poured over the sub-floor. This is the oldest method for producing radiant heat, but the home’s foundation must be able to support the weight of the slab. Concrete is considered thermal mass, so this means it stores the heat that is produced in the pipes. It makes a good source of heat even at night when it is cooler.

Dry installations, rather than fixing the pipe within concrete, place it between plywood sheets that are installed below the floor in an airspace provided. This type of installation is usually less expensive than wet systems but requires higher temperatures because there is air to heat as well. Air does not hold heat like concrete does. Dry installations may also be placed through the joists of a home’s sub-floor. Although there are variations on both wet and dry installations, they are the basic methods for running the radiant heat pipe underneath the floors of a home.

Radiant Heat Pipe

The piping used for radiant floor heating is typically made from copper, but plastic is another material that is frequently used. The preferred radiant in-floor piping is known as PEX or cross-linked polyethylene. It is extremely flexible and resists both freezing and temperatures as high as 200 degrees Fahrenheit. PEX piping is more affordable than rigid pipes such as copper. It is designed to resist internal buildup and corrosion, and it quieter than copper as well.  

In-floor radiant heat piping is a job for professionals. The installation requires numerous tested skills and the manipulation of several of the home's systems including plumbing, foundational, and electrical. Understanding the basics of radiant heat pipe can, however, enable you to discuss the details with the contractor of your choice and make informed decisions about the best course of action for your in-floor radiant heating system.