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Glass &Windows Selection

Radiant Floor Heating

Interest has increased in radiant floor heating with the introduction of nonmetallic tubing and new design, application, and control techniques. Whichever method is used for optimum floor output and comfort, it is important that the heat be evenly distributed over
the floor. Spacing is generally 4 to 12 in on centers for the coils. Wide spacing under tile or bare floors can cause uneven surface temperatures.Embedded Piping in Concrete Slab. Plastic, rubber, ferrous, and nonferrous pipe and tube are used in floor slabs that rest on grade. The coils are constructed as sinuous-continuous pipe coils or arranged as header coils with the pipes spaced from 6 to 18 in. on centers. The coils are generally installed with 1.5 to 4 in. of cover above them. Insulation is recommended to reduce the perimeter and back losses. Figure 20 shows the application of pipe coils in slabs resting on grade. Coils should be embedded completely and should not rest on an interface. Any supports used for positioning the heating coils should be nonabsorbent and inorganic. Reinforcing steel, angle iron, pieces of pipe or stone, or concrete mounds can be used. No wood, brick, concrete block, or similar materials should support coils. A waterproofing layer is desirable to protect insulation and piping.

Where coils are embedded in structural load-supporting slabs above grade, construction codes may affect their position. Otherwise, the coil piping is installed as described for slabs resting on grade.

The warm-up and start-up period for concrete panels are similar to those outlined for plaster panels.

Embedded systems may fail sometime during their life. Adequate valves and properly labeled drawings will help isolate the
point of failure.

Radiant floor heating can be installed in any new or existing building. Residential, commercial, public, or agricultural. It can be installed in concrete or suspended wood floors.

Although hot water can be used with virtually any type of heating system, including forced air and baseboard, we want to talk specifically about radiant floor heat. Whether you are planning new construction or want to improve comfort and reduce costs by updating the heating system in your existing home, business, church or any other facility, you should consider the advantages of installing a radiant floor heating system. With this heating system, heat radiates from the entire floor.

Advantages Of Radiant Floor Heat

No Cold Spots:
With Radiant Floor Heating, heat radiates from the entire floor. You get a warm floor and even heat without hot or cold spots.
Quiet and Invisible:
Radiant Floor Heating is the invisible heating system. You can't see it, you can't even hear it. There's no fan, no ducts in the floor and no radiators along the wall.
With no radiators or duct work to attract and trap dust you'll have less cleaning and there won't be any germs, allergens or dust blowing.
Radiant Floor Heating does not dry out the air like a forced air system and there is less heat loss when doors are opened in the winter. You can even open windows for ventilation without significant heat loss. People with allergies have fewer problems with floor heat.
Improved Comfort
The human body temperature is the highest in the head and circulation is poorest in the feet. Look at the Ideal Heating Curve for the Human Body

The human body is most comfortable with a temperature of 75 degrees F at our feet and a temperature of 65 degrees F at our head. With this temperature curve our feet and bodies are warm while our head is slightly cooler. We feel warm, comfortable and alert.

Now, look at the Radiant Floor Heating Curve - . Radiant floor heating is the only heating system that gives you a room temperature curve that matches the Ideal Heating Curve for the human body. Warm at the floor and cooler at our head. Chart illustrates the room temperature curve you get with forced air heating. It is the exact opposite of what the human body requires. With forced air we can have cold feet, an uncomfortably cool body and we feel tired because the air is too hot in the top half of the room.

Long heat up period

Requires major disruption on existing buildings

Long cooling down period

Cannot respond rapidly to quick temperature changes

Choice of floor finishing requires careful consideration

Changes of floor finish may affect performance

So-called "wet" installations embed the cables or tubing within a solid floor and are the oldest form of modern radiant floor systems. The tubing or cable can be embedded in a thick concrete foundation slab (commonly used in "slab" ranch houses that don't have basements) or in a thin layer of concrete, gypsum, or other material installed on top of a subfloor. If concrete is used and the new floor is not on solid earth, additional floor support may be necessary because of the added weight. You should consult a professional engineer to determine the floor's carrying capacity.

Thick concrete slab systems have high heat capacity and are ideal for storing heat from solar energy systems, which have a fluctuating heat output. The downside of the thick slabs is their slow thermal response time, which makes strategies such as night or daytime setbacks difficult if not impossible. Most experts recommend maintaining a constant temperature in homes with these heating systems.

Due to recent innovations in floor technology, so-called "dry" floors, in which the cables or tubing run in an air space beneath the floor, have been gaining in popularity, mainly because a dry floor is faster and less expensive to build. But because dry floors involve heating an air space, the radiant heating system needs to operate at a higher temperature.

Floor Coverings
Ceramic tile is the most common and effective floor covering for radiant floor heating, as it conducts heat well from the floor and adds thermal storage because of its high heat capacity. Common floor coverings like vinyl and linoleum sheet goods, carpeting, or wood can also be used, but any covering that helps to insulate the floor from the room will decrease the efficiency of the system.

If you want carpeting, use a thin carpet with dense padding and install as little carpeting as possible. If some rooms, but not all, will have a floor covering, then those rooms should have a separate tubing loop to make the system heat these spaces more efficiently. This is because the water flowing under the covered floor will need to be hotter to compensate for the floor covering. Wood flooring should be laminated wood flooring instead of solid wood. This reduces the possibility of the wood shrinking and cracking from the drying effects of the heat.

Dry system radiant flooring  
Electric Radiant Floors  
Floor Heating Control Systems  




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