Q - We like to use our outdoor patio and deck during the evenings in the fall and spring, but it gets a little chilly sometimes. Is there an effective method to heat it just enough to be comfortable? L.L.
A - Often you just need a slight amount of heat to give several more months of use of your deck. Depending on the size and orientation of the deck to your house, you may be able to operate heaters inexpensively.Radiant heaters are the only effective type for heating an open outdoor area. Radiant heat warms people and objects on the deck, not the outdoor air. This is exactly the way the sun feels warm on a chilly day.
There are several types of radiant heaters that you can use. They can either be powered by natural gas, propane or electricity. Since a very high temperature is needed for effective outdoor radiant heating, gas or propane heaters provide the greatest output. Low temperature radiant heat, like the type used indoors, is not effective outdoors.
There is one radiant heater specifically designed for decks. It mounts a 20-lb. propane tank (same size as for most barbecue grills) in the base. Set it in the area of the deck that you want to heat and switch it on. You can expect about 10 to 15 hours of heat from a standard propane tank.
It has controls similar to a gas barbecue grill. At the 50,000 Btu output, it effectively heats a 15-foot circle around the heater. You can also run a natural gas line to it, but then its location is fixed.
If the area of the deck most commonly used is near your house wall, you can install a horizontal gas radiant heater high on the wall. This provides a more rectangular radiant-heated area of your deck.
Electric radiant heaters can also be mounted on the wall. In order to get enough heat output, they must be wired to a 220-volt line. Depending on your local utility rates, an electric radiant heater will cost about twice as much to operate as an equivalent-sized gas heater.
Partially blocking the wind helps significantly. You can build a low brick solar wall on the west side of your deck. In the afternoon, it is exposed to the sun and absorbs heat.
In the early evening, it blocks some of the wind. As the air flows across the warm bricks, it is heated a little. The warm bricks also provide some radiant heat when you are sitting near them.
You can write to me for UTILITY BILLS UPDATE No. 010 showing a list of manufacturers of patio and deck heaters, the heat outputs, and the costs to operate at various utility rates. Write to James Dulley, The Deseret News, 6906 Royal Green Drive, Cincinnati, OH 45244. Please include $1.00 and a self-addressed business-size envelope.
Q - We are laying ceramic tile solar floor in our sun room. I was wondering if the type of adhesive we use will affect the solar heat transmission to the concrete floor below? B.G.
A - Ceramic tile is one of the most attractive and functional floor coverings to use for a solar floor. Darker colors are most effective for absorbing and reradiating the heat back into your sun room.
Although most adhesives are good insulators as compared to the ceramic tile, the cured thickness is very thin and they won't block much heat transfer. A thinset mortar is a better choice than ready-to-use adhesives and provides a stronger and more compatible bond to the concrete.