We often don’t even think about how our homes stay warm in winter. Most of us just set the thermostat and forget it. Essentially, any new home will use some form of furnace or heat pump in conjunction with central air. Commonly called HVAC, forced air systems have the benefits of easy operation and dependability.
Until HVAC was widely in use, the traditional radiant heating method was the preferred way to heat a home. An example of radiant heating would be a space heater, baseboard heater, and the traditional radiator we’ve all seen. Today, the primary use of radiant heating in new construction is radiant flooring. Both styles of heating have their advantages and disadvantages, which we will discuss here.
Radiant vs. Forced Air: Key Differences
The cost associated with installing radiant heating depends on the same factors as any home improvement project, which are the size, location, and function. The type of system you use, where it is going, and the problem it solves can change the project cost dramatically. The type of radiant heat system used will usually depend on the cost and how big the project will be. For instance, installing any version will be easier if the room(s) is already under renovation. Therefore, consideration should be given to the scope of the project to keep costs under control.
A typical room using radiant floor heating will use about the same, or up to 15% less energy than a similar forced air system. Radiant floor heating systems are very efficient to operate, and heat the room evenly. As opposed to the traditional space heater or radiator, there are no cold spots, nor a need to increase ventilation because an area has become too warm.
Will my investment in radiant floor heating pay for itself? The short answer is, maybe. The ROI is based on the cost vs. the effective life of the system, so the longer you own your home, the greater the ROI will be. Radiant floor heating is more expensive to install than a similar forced air system, but will likely last up to three times longer. This is due in part, to the efficiency of radiant heating as well as fewer moving parts. Wear and tear on a radiant system is also very low compared to a forced air system, such as a furnace.
One commonly overlooked benefit of radiant heating is that it is silent. We’ve all been in homes with noisy forced air systems that can be quite annoying. Radiant systems have no fans, nor ductwork to transfer vibrations to the floor.
Forced Air (Central HVAC)
One advantage forced air systems have is the initial cost. Forced air systems will initially cost about 50% less than a radiant system heating the same space, but much of the efficiency can be lost due to poor installation. Although forced air systems will require more maintenance than a radiant system, the components are generally accessible. This is in contrast to radiant heat flooring systems, which tend to require much more demolition to repair.
Forced air systems do a much better job of eliminating cold spots often associated with space heaters and radiators. Because the air is constantly moving, fresh air is brought in from outdoors and circulated around the home evenly. However, forced air systems depend greatly on how well they are designed, so care should be taken to hire a reputable contractor.
In contrast to radiant systems, all HVAC systems will have at least one air filter that captures airborne contaminants. The return then recirculates the air back into the system. For families with allergies, hepa filters can also be added.
Forced air systems can usually be installed in just a day or two. Because the mechanical components of a forced air system must be accessible by building code, repairs and maintenance are also simple to accomplish. Technicians in the field must be licensed as well, since these systems can involve the use of freon.
Radiant vs. Forced Air: A Detailed Comparison
In this section, we will go into a few more key differences between a radiant heating system and the more common forced air system. Today, we will focus on the common applications for each system as they are used today, including radiant floor heating, heat pumps, and furnaces.
Radiant Floor Heating Types:
Today, radiant heating is used primarily for under floor heating. As previously mentioned, radiant heating is more expensive per square foot than forced air, so often it will be used as supplemental heat. The most common location for radiant floor heating is the bathroom.
This type of radiant heating uses a flexible mat that has small wires molded into it. These mats are connected like a puzzle, with each mat interlocking together. This method is not usually suitable for rooms with irregular shapes, as the mats cannot be modified to fit into nooks and crannies. However, these mats are sometimes used for spot heating, such as a small area near a sink or shower.
With this method, the wire producing the heat is embedded in mortar or similar material. The advantage of this method is that it can be customized to fit any floorplan. The downside is that the installation is more expensive than mats, due to the additional materials and labor required.
Hydronic radiant floor heating, on the other hand, can cost as much as double. Hydronic systems incorporate the use of PEX, which is polyethylene tubing, to circulate heated water under the floor. PEX is a very durable plumbing material, but will still require regular inspection to prevent water damage should the tubing develop a leak. Hydronic systems can also raise the floor height, so this system is typically used when the floor will be replaced anyway.
Considerations When Using Radiant Floor Systems
There are several styles of radiant floor heating, and some cost more than others. Electric systems are typically easier to install and will usually be the least expensive version. The common electric mat system, for example, will often cost 3.00 to 6.00 per square foot for the materials, and another $2.00 to $4.00 if you hire a professional. Costs will vary from region to region.
Typically, the additional weight added by an electric heating system is negligible and will not require additional floor support. However, there are instances where floors are so out of level that a floor leveling compound is needed. Leveling compound is much like cement, and can add significant weight to a floor. Depending on the floor area to be heated, additional floor support could be required.
As mentioned earlier, there is virtually no maintenance required for electric radiant heating systems. There are no moving parts to wear out or make noise, so periodic inspection for common radiant floor heating problems is often all that is required.
The pros do not recommend attempting to install radiant flooring under hardwood, as this style of flooring is attached to the floor with nails. A single errant nail can break the wire or tubing and cause the system to fail.
Forced Air Types
Heat pumps are very common in areas where access to heating fuels are limited or unavailable. These systems provide both heating and cooling by either pushing heated air into the home, or pulling heat from a home, much like a refrigerator. A heat pump may be divided into separate halves, called a split system, or an all-in-one package unit. The design of the home will often determine which type is used.
In a furnace system, air is usually heated via some form of heat exchanger. These systems generate heat by burning natural gas, oil, or liquid propane and using this heat to warm the circulating air. Furnaces tend to be inefficient compared to heat pumps, but technology has improved the efficiency in recent years. One disadvantage to a furnace is that in climates where it is needed, air conditioning will need to be added.
Which is Better: Radiant Heat or Forced Air?
Each style of heating has advantages, depending on the application. For example, in the far northern United States, radiant heating tends to be used in conjunction with forced air due to the long winters. In other areas where the climate is more moderate, radiant heating is often used only in bathrooms, such as in front of a jetted tub.
Generally, forced air systems are used as the primary heating and cooling system in a home due to the cost, efficiency, and ease of installation. This type of climate control will often be the best solution for the majority of homes, however, in some climates a forced air system simply is not sufficient.
A forced air system relies on a process called a load calculation, which is done by a licensed HVAC technician such as Ideal Air. This calculation takes into account the style of the home, how well the home is insulated, and even the efficiency of the windows and doors. This information is then used to determine the size of the system required and the location of the ductwork. If done well, a forced air system is efficient, relatively quiet, and reliable.
Keeping our families comfortable year round can be a challenge. Although radiant heating and forced air are both dependable, the biggest factor for most users is how well the system does it’s job. Before you decide which system is best for you, consider the return on investment and how satisfied you will be with the results. Doing so will help avoid buyer’s remorse and provide a comfortable space to enjoy.