GREEN Topic: Radiant Floor Heat
Technology Snapshot & Benefits: Radiant floor heating can be extremely cost-effective and comfortable. There are three types of radiant floor heat: radiant air floors, electric radiant floors, and hot water radiant floors. Hot water radiant floors, or hydronic systems, are the most cost-effective systems for homes or buildings in heating-dominated climates. Hydronic systems heat water in a boiler and pump the heated water through tubing underneath floors. Most find radiant floor heat to be one of the most comfortable types of heating, because heat is evenly distributed from the floor, warming up the feet and body first. The benefits to radiant floor heating are numerous and include increased levels of comfort due to the silent operation of the system. Radiant floor heat eliminates drafts and dust problems associated with forced air systems. Additionally, radiant floor systems are invisible. There are no heat registers or radiators.
Estimated Cost Savings: The estimated cost savings associated with the use of radiant floor heating range from 10-40% on utility bills. Due to the fact that radiant heated floors distribute heat evenly, homeowners can set their thermostat 2-4 degrees less than in a forced air heating system, which leads to reduced energy costs. Contact your local utility company to confirm what a 2-4 degree temperature decrease would equal in savings.
Compared to other hydronic heating systems, radiant floor heating allows for lower boiler temperatures, saving energy and increasing boiler life expectancy. A 45-year life is not unusual.
Issues: With radiant floor heat, some floor coverings perform better than others. Ceramic flooring is the most common. If you want carpeting, install a thin carpet with dense padding and use as little carpeting as possible. Some floors take longer to heat than others. If a floor is allowed to cool completely, make sure to give adequate time for the floor to heat-up.
When working with a hydronic system, it needs to circulate water continuously using valves and manifolds. These valves and manifolds can be prone to mechanical and maintenance issues as well as sedimentation. If a hydronic installation develops a leak, it can be challenging to repair.
Regional Issues: Radiant floor systems can also be used to cool spaces. Currently, the available systems are only appropriate for dry climates.
Installation (Getting It Done): The three types of radiant floor heating breakdown further when installed into “wet” or “dry” installations. During the older form of installation, a “wet” installation, cables or tubing are inserted within a solid floor. The solid floor can be a layer of slab concrete, gypsum, or any other material that is installed on top of a subfloor. When applying a “wet” installation consult a professional to determine the floor’s carrying capacity. In a “dry” installation, cables or tubing run in the air space beneath the floor. “Dry” installations are increasing in popularity due to the fact that they are cheaper and faster.
Be sure to get two or three (or more) bids from designers and/or contractors to gain immediate perspective on the actual costs of radiant floor heat equipment installation in your area.