If you're installing replacement windows or doors yourself, it's vital to make sure you follow all the rules - if it isn't level or plumb, it won't seal tightly, allowing cold air and damaging water to leak in. Follow the manufacturer's instructions carefully, and take your time - it won't be easy to fix mistakes later.
Before the finishing trim is hung, check all the windows in your home with a carpenter's level and use shims to correct any that might be off-kilter.
After the windows are hung, be sure to add fiberglass or foam insulation in the larger gaps and caulk the edges of the frame and casing. Remember - a gap as small as 1/16th of an inch can let in as much cold air as leaving the window open three inches!
Maintaining your windows
Ongoing maintenance is a must to keep cold air and moisture out. Weatherizing windows is easy and inexpensive. In fact, an investment of $50 in weatherizing supplies can reduce heating costs by two to three times that much!
Another area many homeowners overlook is the window glazing - the putty that secures the glass to the sash. Over time, the glazing can harden, crack and fall off - leaving your window panes loose, drafty and dangerous.
You can purchase window glazing at any hardware or home improvement store. Just chip or scrape off the old glazing, clean the window thoroughly and install the new glazing with a putty knife or caulking gun. Some types of window glazing require a coat of latex paint for a weatherproof seal.
To prevent condensation - and the accompanying mold and mildew - be sure to monitor the humidity level in your home.