Things you should know about windows before buying a house


There’s a lot to consider when you’re deciding to buy a home. One important factor is windows, which occupy around 15 percent of a home’s wall space on average. Here’s a guide about what to look for and understand about windows when you’re in the market to buy.

First, on a practical level, take note of what material the windows are framed with. Vinyl windows are easy to keep clean and fairly energy efficient. Wooden windows need more work to clean and they can swell and contract, but they have very good insulation properties. Aluminum windows tend to be somewhat more moderate quality and not as good at conserving energy, although thermally-broken aluminum windows with a barrier between the exterior and interior have decent energy efficiency.

Composite windows are made of several different combined materials such as aluminum or vinyl-clad wood. They’re the most energy efficient and durable, and are at the higher end of the window market. If you see just plain vinyl or wooden frames in a home, keep in mind these are prone to enlarging and shrinking with changing temperatures, causing draughts and condensation problems.

The second major practical factor is glass type. Low-emissivity, or Low-E glass, saves a bundle on energy bills because it reflects the sun’s rays instead of absorbing them. This keeps heat inside the house in winter and out of it in the summer.  For increased security, particularly in doors or other vulnerable areas, look for toughened glass, which is five times stronger than regular glass. Laminated glass is another option, is strong and break-resistant, and tinted glass is desirable in areas requiring privacy.

The third big consideration is window glazing. Single pane windows lose as much as 60% of interior heat during the winter, whereas double glazed windows with two panes separated by an airtight gap are much more energy efficient and resistant to mold and moisture. In fact, double glazed windows will save you up to 55% on energy bills and up to 80% if they are made with Low-E glass.

Many homes now are built with double glazed windows, but watch out for single pane glass in older homes especially and keep in mind it may be a hassle in terms of heat loss and condensation buildup. That said, older windows are not necessarily a deal-breaker; there are many ways to restore and upgrade older and single pane windows that can still be worth your while without necessarily requiring a full replacement.

Lastly, on the practical side, consider the window’s energy rating by inquiring about U-value and solar heat gain coefficient (SHGC). U-value means the amount of incoming or outgoing heat that a material transfers. The lower a window’s U-value, the higher its ability to insulate your home, thereby reducing energy bills. SHGC means how much solar heat windows and doors let into the house. A lower SHGC means that less heat will be absorbed in through windows, making air conditioning in the summer less expensive. Another factor to consider is that light-color shades can cut down a window’s solar heat gain by as much as 43 percent, while awnings reduce it by as much as 77 percent.

When examining the windows in a house look for any signs of corrosion or deterioration around the frames and hold your hand to feel for any air escaping in from outdoors. Windows usually need replacing every 20 years or so. If the windows in a home show signs of deterioration at the edges or air leaks, they may be nearing the end of their life cycle.

On the functional side, think about whether you would prefer a casement window that swings outward and is hinged at the side or a single-hung or double-hung window where one or two vertical windows can slide up to open. Casement windows are particularly good as transom, awning, and picture windows. Or perhaps you’d prefer an awning-style window that swings open at the bottom and is attached by a hinge at the top?

In the end windows are a matter of both functionality and taste. Picking a home with windows you like and that work for your needs is an important part of buying a home.