Here's another great tip from BobVila.com. Whether you re building a whole house or just adding a new bathroom, one of your first decisions has to be how you re going to heat the new space. According to the U.S. Department of Energy, radiant heat is more efficient than baseboard or forced air systems. Rather than just blowing hot air around the room in bursts, radiant systems slowly and steadily charge the floor with heat, keeping it where you want it, longer. Hydronic, or water-circulating, radiant systems are best for new construction or large additions. They come in many forms, for installation just below the subfloor between the joists, directly under tile or hardwood flooring, or even inside a concrete floor slab. Where you only need to heat a small space, like a bathroom, electric radiant is an easy luxury option. Electric radiant mats can be installed directly under tile and are ideal over a concrete subfloor. Set the timed thermostat to turn the system on only when you ll be using the room, like the morning when you shower, and it ll use less than 15 cents of electricity per day. This way, you don t have to make room for ductwork or baseboard units when you add a bathroom. On a cold winter morning, your toes will thank you for choosing radiant heat! Find out more at BobVila.com: The ultimate home improvement web site! BobVila.com 2008

The PEX tubing is set in the concrete and will circulate hot water used to heat the addition. Jason McKinnon of Viega North America reviews the features of PEX tubing. PEX is electronically cross-linked polyethylene tubing that is made to be stronger and resistant to high temperatures and pressures. The PEX tubing was placed in the concrete slab. The concrete acts a low-temperature radiator for the tubing. High temperature water will be pumped through the coils and heat will dissipate into the slab. A heated slab acts as a radiant heat source for the home. Tim Cutler of TJ's Plumbing & Heating reviews how the tubing was placed within the slab. In a radiant-heat application, the tubing is evenly spread out across the floor. With radiant heat, the air is not heated, only the floor. The heat is modulated according to outside weather conditions so a precise amount of heat is sent through the coils to warm the building's interior to the desired temperature. A heat/loss analysis done on the home indicates that the tubing should have nine-inch spacing for five circuits. During manufacturing, the tubing has 10,000 volts sent through it which cause the molecules to cross-link. This makes the tubing virtually indestructible. An oxygen barrier is sprayed on it to protect the boiler and the heating system from oxygen infiltration, which causes cast iron boilers to deteriorate. A foam stapler pushes plastic clips with prongs into the foam decking to secure the tubing in place.

Bob visits with Mark Lundquist of Burnham Hydronics to check out the boiler for the hot-water heating system being installed in the Mashpee, Massachusetts, affordable homes. This Burnham Spirit model is a medium efficiency, easy-to-maintain, sealed-combustion unit. Since it is sealed combustion, it pulls the air it needs directly from the outdoors and vents to the exterior without the use of a chimney or flue. This enables a homeowner to close off the space surrounding the boiler without worrying about available combustion air for the furnace. This model uses standard parts, so any repairs will be fast and easy. The boiler is made of cast iron and has a 25 to 40 year life expectancy. It operates at 84 percent efficiency, so the homeowner will use energy dollars wisely. Charlie Delvecchio of Cape Plumbing breaks out the cost of the boiler to about $1,500 and the baseboard tubing for another $6,000, for a total cost of $7,500 for installation of the home heating system. The domestic hot-water tank is linked to the heating system as hot water from the boiler passes through a coil in the insulated hot-water tank, warming the household water through energy exchange. If the water is maintained at the proper temperature just from this passive exchange, the boiler will never be called upon to heat water for faucets and showers.