Other alternatives are made of a polyurethane foam insulation core - offering six times the energy efficiency of wood - faced on both sides with vinyl or aluminum. These typically cost for a 6-foot-wide door. All well-made nonwood doors are designed with thermal breaks (separations between indoor and outdoor surfaces that block the conduction of heat or cold.) Glazing options Of course, the largest part of a glass sliding door is glass. To make a door truly energy efficient, high-performance glazing is key. Fortunately, this is standard with most high-quality sliders. You''ll find double-paned glass with low-E (low energy) coating and, in some cases, argon gas filling. Low-E reduces heat transfer and protects against ultraviolet damage; argon gas filling provides greater insulation. Some manufacturers let you specify the glazing you want when you order. Where sun-caused fading or damage can e a serious problem, you may want to opt for glass with a solar bronze or solar gray tint to reject ultraviolet rays. In addition, some companies offer decorative stained or beveled glass with true brass caming (leading). For bathrooms or other places where privacy is a concern, obscure glass is available.

Now the nation''s leading producer of steel doors, Therma-Tru helped build the market for that product category. The effectiveness of that pioneering effort is reflected in the market share steel currently holds. For the past two decades company has focused its commitment to quality fiberglass and innovation on doors, the fastest-growing segment within the exterior door category. We were interested in differentiating ourselves from the rest of the market -- that''s the only way to be profitable in the long term recalling hiscompany''s motivation for pursuing fiberglass. Therma-Tru recruited a ream of engineers and assigned them the mission of developing a new product that would put perform both wood and steel. The team blended fiberglass and resins to invent a sheet-molding compound, as well as the tooling to transform those supplies into a door skin. After extensive laboratory and field testing, the fiberglass industry''s first door hit the market: the Fiber-Classic.

The Fiberglass Smooth-Star door line, the industry''s first door created from fiberglass to capture the smooth look of doorhardware painted wood, has been awarded a U.S. Patent. Doors are strategically engineered for exceptional durability and appealing aesthetics. SmoothStar doors can be painted to a high gloss with no distortions of the surface. Doors are available with embossed panels or three-dimensional raised panels and also in new 8-foot heights. Doors in Therma-Tru''s Classic-Craft line for interior use have a more wooden appearance owing to an innovation in the six-year-old product line. According to the company has developed raised paneling for its doors that provide higher fidelity and sharper detail. The panels are layered over a polyurethane core that, according to Therma-Tru, insulates five times better than wood. Because f the product''s durability, which includes resistance to weather-related cracking, Therma-Tru is offering the doors doorhardware with a lifetime warranty that far exceeds the typical five-year warranty that wooden doors have. This product makes all the sense in the world which sells these doors out of its showroom. The doors are selling really well and we are making doorhardware special orders for them.