Q: What is radiant heat?
A: Radiant heat is transmitted by radiant energy similar to that which the sun produces. It is run usually in the floor. The large heat mass allows you to use much lower temperatures. This technology has been around since the Roman era.
Q: Is ceiling radiant heat uncomfortable?
A: Not at all. Remember radiant heat is not a convective heat. It doesn’t heat the air, it heats the objects in the room so, if you insulate properly, it takes the path of least resistance and can work from the ceiling also.
Q: How can I zone radiant heat?
A: You can zone radiant heat the same way you would conventional zones. If you use circulators, you zone each header with a separate circulator. If you choose zone valves, you can use one larger header and zone the areas off that.
Q: How is radiant heat installed in a concrete floor?
A: First you must insulate the area under the slab. Remember, this type of heat takes the path of least resistance. Then you can either run 4″ square mesh and attach the heating tubes one foot on center to that or, if the floor is insulated with 2′ styrofoam, we use staples to hold the tubing down. It is recommended by the tubing company to pressurize the tubing while the floor is being poured so that you can tell if there is a puncture during this part of the installation.
Q: What insulation is used in the slab for radiant heat?
A: We generally have the concrete company put down 2″ blueboard insulation. But there is a much thinner bubble type insulation if, for some reason, 2″ is not going to work in your application.
Q: Can I put wide wood plank flooring over radiant heat?
A: Yes, but it is critical that your surface temperature does not exceed 85 degrees to prevent the boards from warping.
Q: Can you turn hot water baseboard heat into radiant in-floor heating?
A: No, it will not disperse and heat evenly under the floor structure like tubing that is in contact with the floor at 8″ intervals.
Q: Can I tap a baseboard radiator for radiant heat?
A: No, your design temperatures are generally too far apart.
Q: Can radiant heat leak gas?
A: It doesn’t leak gas but the tubing you put in must have an oxygen barrier to protect the boiler from fresh oxygen attacking the unit.
Q: How can I size a radiant heat boiler?
A: You still need to do a heat loss calculation on the house or area you are going to put radiant heat in.
Q: Infrared or radiant heat – which is better?
A: These are two different types of radiant heat. Infrared is usually used in a commercial application or for spot heating cold areas in a commercial application. Radiant heat is used more commonly in a residential setting but can also be used in a commercial application such as in offices.
Q: Is it cost effective to convert to a radiant heat system?
A: It depends on the type of system that exists and the length of time you plan on living in the house.
Q: What do I need to know about radiant heat systems?
A: Although it isn’t the least expensive system to install, it is the cheapest and most comfortable heating on the market and it will pay for itself.
Q: What is better – convective or radiant heat?
A: Radiant heat by far is the most economical to operate and the most comfortable. Anything within contact of the floor becomes a heat source and, since the heat median is the floor (in most cases), this area comes in direct contact with one of the more sensitive areas of our body, our feet. Warm feet in winter = warm comfortable bodies.
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