A sunroom could add space and with heating bills

Posted March 09, 2026 6:00 am

James Dulley

These do-it-yourself kits are lightweight and easy to build. The window panels can be removed to create a screened porch. Courtesy of SunPorch

Q: We could use some extra space, so I am considering adding a sunroom. It will help heat my house and is cheaper than a typical room addition. What design features should I consider?

A: If you are looking for relatively inexpensive additional floor space, adding a sunroom is a good option. Not only are the material costs much less than adding a conventional room, but it can help to reduce your heating bills. If you design it properly, it can actually also reduce your summer cooling bills by creating natural ventilation.

This schematic shows how to utilize thermal mass (water barrels and concrete floor) and vents to circulate hot air into house. James Dulley illustration

Many companies sell sunrooms which are often basically in kit form, but most want to also do the construction work for you. This is not only to make more profit, but building one is typically not as simple as it looks. Most of these sunrooms use extruded aluminum frame members which may be difficult to cut without the proper saws and blades.

I convinced a sunroom company, who always does the installation, to send the components to me since I am an experienced do-it-yourselfer and a mechanical engineer. It took me three weeks of hard work to build it over a concrete patio. They told me it typically takes two of their factory-trained workers only two days to build one.

This do-it-yourself sunroom is designed around recycled storm windows and doors. Notice the windows near the peak and the roof vent to avoid summertime overheating. James Dulley photo

In order to use the sunroom to capture enough winter solar heat to help warm your house, it should face due south or southwest. It should be open to the house or have fans to circulate the solar heated air into the house. Adequate solar mass, from bricks, stone, water barrels, etc. is needed to store the solar heat and minimize overheating.

A sunroom which is designed and oriented properly to capture solar heat will typically overheat in the summer. Since you plan to use it for additional living space, it will need summertime ventilation and movable shading. Even so, it will likely be uncomfortably warm on the hottest days. I installed a vented, tinted skylight in mine,

Building a sunroom yourself from scratch is the best way to keep costs down and capture the most solar heat. Depending upon your home's orientation to the sun, trees, lot size, etc., you will have the design flexibility to build a nonrectangular sunroom to accomplish your goals of heat and extra living space.

For most do-it-yourselfers, using 2x4 lumber farming is easiest and least expensive. Draw up a basic design you desire. Visit local window contractors and home centers stores to see what size windows they have. Often someone returned or did not end up buying their custom-size windows and you can buy them at a deep discount. Plan your final size on them.

To use the sunroom year-round and for solar heating for your house, select double-pane windows as a minimum quality. Single-pane windows are less expensive, but they are typically only used on three-season sunrooms. Tall old storm windows can be effective and cheap for a three-season sunroom. Check at recycled building product outlets which are becoming more common.

Using standard lumber, a lean-to design of sunroom with a slanted glass front is easiest to build yourself. There is less framing to build and much less roofing. This design will capture a lot of solar heat during winter, but it is difficult to control the overheating during summer. Since your family can be outdoors more often during summer, you may just close it off during the peak heat.

Q: My father has a small Amish-built log cabin. The walls are made of 4x8 logs. Even with the fireplace going, it is drafty and chilly. How can we add wall insulation to make it more comfortable?

A: One of the attractive qualities of this type of cabin is the log appearance. There is no good method to add wall insulation without covering the outdoor walls or losing too much interior floor space.

Adding more attic insulation would be effective. Make sure all the mortar on the walls is sealed and not leaking. Add an outdoor combustion air duct for the fireplace. This will reduce the drafts and make you feel warmer.

• Send questions to James Dulley, Daily Herald, 6906 Royalgreen Drive, Cincinnati, OH 45244 or visit www.dulley.com.