We’re all aware to some degree the energy savings that can be realized with the right windows in your house. And, many of us have faced the dilemma of moving forward with these efficiency upgrades while limiting the aesthetic architectural damage that might come to a coveted home as a result.

Many of the finest homes in the country lay in old well established neighborhoods and were built some 80+ years ago. And their character, their charm, is often the result of beautiful leaded windows or small divided light windows. But, while maintaining them in good condition can help, generally speaking, from every aspect of modern window science they fail – bad seals, single pane, and no coatings.

I believe that historic homes require some energy math to find saving improvements where they can best be implemented. Extra attic insulation, high efficiency furnaces or boilers, tight seals on all of the windows and doors and basement insulation are effective measures. About 10% of your heat is released through uninsulated windows but the biggest bang can first be had from these other improvements. As for the windows, it’s likely they’re not all of the intricate design variety and replacing the ones that aren’t can help. Finally, storm windows can be installed on the interior or exterior of the home during the coldest months for these instances where history must take precedence.

Window Replacement Options for an Older Home

The 1940’s marked a time where windows began to open up, so to speak. Divided lights either with mullions or lead were used less as people began to desire clear views of the exterior. So – here we are, undeterred, and able to explore all possible window replacement options.

Here are some of the choices available today:

• Frame material: Wood, Vinyl, Aluminum, Fiberglass, Vinyl Clad Wood, Aluminum Clad Wood.
• Insert vs. Full Frame Replacement
• Fixed, Double-Hung, Casement, Awning, Sliding, Screened
• Glass: Low-E, Argon gas filled, ¼” or ½”, or triple paned

Replacement windows can add a great degree of comfort to your home. Lower conduction means warmer windows, lower convection means less drafts, and lower radiant heat transfer gives us benefit from the sun during all seasons.

A few things to note:

• Aluminum should be avoided as it transfers heat. It can be ordered with the proper thermal breaks to minimize this where the architecture calls for it.
• Wood requires the most maintenance, but looks best, and since painted, is the only choice that allows you to change color.
• Vinyl is very durable and, since the color goes all the way through the vinyl, some soft scrub can bring them back to near new condition.
• Low-E, argon gas windows cost on average about 10% more than just clear glass. However they are the most energy efficient window available and a rough rule of thumb is a payback of about 4 years.

But what if you don’t want to replace the windows?

• Drapes which are closed against the wall at the window top, sides and bottom and are lined with a light colored material trap the hot dead air of summer and the cold dead air of winter. The key is restricting airflow and this should also include overlapping center.
• Horizontal blinds are best able to reflect unwanted sunlight and it’s heat generation, and blinds made of vinyl or wood are least conductive and can provide some incremental heat savings when closed.
• Outside shading can be particularly effective in warm climates where your primary mission is cooling. Similar to this, the Low-E coating is placed on the inside glass where heating is primary and on the outside glass in more cooling-centric environments.

Good windows, window coverings, and good light management can save you energy, money and give you comfort – of the cozy type. With the efficiencies of today’s windows, larger windows that provide more natural light can help save on lighting and should be considered as a part of your window replacement plan.

Michael Samsel is an entrepreneur and writer on the subjects of home design and green home practices. A co-founder of StylishHome.com, their “good design” mission emphasizes individual design personality, the eclectic and hand-made, and a commitment to green home pursuits.

Not quite ready to replace those old windows? You can still make them more energy efficient with window coverings, including shades and window film.

Image credit: Orin Zebest at Flickr under a Creative Commons license