I want to add an efficient kit sunroom on the south of my house. What design features should I look for if it will be used for living space and plants?
If you are looking for an attractive, efficient sunroom, you probably don't want a kit. Most sunroom companies use factory-trained local contractors to build their rooms at your home. An efficient sunroom is a more complicated structure than you might realize.
Some simple kits use aluminum frames and clear plastic windows. They can be converted to a screened porch during the summer by snapping out the self-storing plastic windows. They are functional and not difficult to build, but they have somewhat of a "kit" appearance.
Another option are ready-to-install sunrooms, delivered assembled. These are high quality with beautiful solid wood frames. Once the foundation and slab are ready, you can enjoying the sunroom the day it is delivered. This is a more expensive option, but you can finish the wood yourself to save money.
You mentioned the south side of your house. This is a good location in cold climates if you want to use the sunroom during the winter without dramatically increasing your heating bills. In warm climates, or if you plan to use it as a three-season sunroom, an east or west orientation with deciduous trees for efficient shading may reduce summertime overheating.
The two key features to consider are the frame material and the type of glass. Aluminum frames, anodized or powder-coated, require the least maintenance and are very strong. An aluminum frame should have a nonheat-conducting thermal break between the indoor and outdoor surfaces. This is more efficient and reduces wintertime sweating.
Wood frames are the most attractive and offer more decorative curved eave options. Wood is typically more expensive and requires periodic maintenance. If you like the appearance of wood but not the hassles, select a combination wood/aluminum frame. The exterior is aluminum, but the interior is stained natural or painted wood.
Select double-pane glass with a low-emissivity coating and argon gas in the gap. This will be efficient year-round, and the low-e coating will block more ultraviolet rays. This will reduce fading and deterioration of carpets and furniture, and your plants will thrive better with fewer UV rays.
Include some type of movable shading and ventilation. "Intelligent" venting skylights and inlet vents open at a preset temperature and close if it rains.
Write for, or download at www.dulley.com, Update Bulletin No. 992, buyer's guide of 12 efficient sunroom/kit manufacturers listing styles, frame/glazing materials, ventilation/shading options, features and passive solar heat-producing tips. Please include $3 and a business-sized, stamped, self-addressed envelope. Send to the address at the end of this column.
James Dulley is a mechanical engineer and do-it-yourselfer. Send questions to James Dulley, The Sensible Home, St. Petersburg Times, 6906 Royalgreen Drive, Cincinnati, OH 45244. Visit his Web site at www.dulley.com to download bulletins, tour his energy-efficient home, post questions for other readers and find other information.