What are the advantages of hot water in-floor heat versus baseboard heating?
Radiant in-floor heating systems cost more than baseboard systems, but for many Alaska homes it’s worth it. They consist of a looping pattern of tubing installed in the floor, specifically sized and spaced to release a given amount of heat from hot water flowing through the tubes. The installation can be “wet” or “dry.” In a wet system, also known as “slab heating,” tubing is embedded in a poured concrete or gypsum floor. Dry systems route the tubing either under or on top of an existing wood subfloor. Depending on the insulative properties of the floor covering (such as carpet), dry systems may need to operate at higher temperatures to perform as well as wet systems. In both cases, insulation is often added under the tubing to ensure most of the floor heat travels upward rather than downward into the soils around the foundation.
People tend to love in-floor heat because it makes their home more comfortable. With heat being emitted over such a large surface area, homes with warm floors feel more comfortable even if air temperatures are slightly cooler, which often leads to lower thermostat settings.
From an energy savings perspective, hydronic in-floor heating runs significantly cooler than hot water baseboards. For instance, water temperatures in the tubing running through a concrete slab usually range from 80-130 degrees Fahrenheit while baseboards operate between 130-165 degrees F. Usually, lower water temperatures needed for slab heating allow the boiler to run cooler.
A cooler-running boiler has several advantages, such as less heat loss up the chimney when the boiler is off. Similarly, the boiler has less jacket loss, where heat is lost from the boiler to the room. Cooler water heating can also make the best use of a condensing boiler, which can operate at lower temperatures and generate efficiencies as high as 94%. Conventional boiler efficiencies top out around 87%. When it comes to conventional boilers, cooler operating temperatures produce less system stress, which can extend the service life of the appliance.
Although the initial costs are higher, the long-term benefits of hydronic floor heating are worth considering, especially in a climate like Alaska.