By Jim Donovan

By Jim Donovan

PHILADELPHIA (CBS) — Have you considered replacing your windows? New windows can help reduce your energy costs, improve your family’s comfort and improve the overall look of your home. But it’s not a project that should entered into lightly. In this week’s Angie’s List report, Jim Donovan shows you what you need to consider before replacing your windows.

Lori Torres’ century old home was in dire need of new windows.

“We’d had them for a very long time, they were at least 25 — if not 30 — years old, and so they were old wood windows that were letting in the cold air in the winter, the warm air in the summer and starting to rot a little bit. Some were in worse shape than others, but we knew we needed new windows for our old house,” said Toress.

If you’ve been in your home many years, it may be time to consider having new windows installed — a decision that can really pay off.

“Your return on investment can be a really good return in your heating and cooling bills throughout the year, but you need to live in your house for a period of time before you realize those savings, which can be as much as seventy percent,” explained Angie’s List founder, Angie Hicks.

But window pricing varies dramatically.

“It depends on the style, the size and even the type of window. For example, a triple paned window is going to be much more expensive than a single paned window, but you are going to get a lot more energy efficiency out of the stronger window, so be sure you’re getting several estimates and talking to the contractors about what type of windows will best fit your needs,” said Hicks.

And do your homework before hiring an installer. If they’re not installed right, they won’t be as efficient and poor installation could also void your warranty.

More from Angie:

Good replacement windows are durable, easy to maintain, provide better security and reduce glare and outside noise.

• It’s time to replace when you notice: Wood rot, fog in between the glass, and drafty windows are some common signs.

• Design preferences: Because windows supply one major aspect of a home’s character, mismatched, faded and broken windows detract from its beauty. Whether your need for windows is aesthetic, functional or both, windows can be made to meet practically any need.

• Various materials: Wood, vinyl, metal and fiberglass are the most common choices.

• Look at the brands: One of your best guides to the quality of a replacement window is the manufacturer’s warranty. You certainly can save money otherwise, but sticking with well-known brands offers the security of a strong company name and generally, better warranty service. Shopping with brands can add convenience since you can visit their physical or virtual showrooms. Some even have computer programs that give you an idea of how a particular window will look in your home.

• Window prices: Costs can range from $200 to $1,000 or more each window, depending on the material, size and style. Some windows may be eligible for a 10 percent federal tax credit (installation costs are not included).

If you’re in the market for new energy efficient windows, look for these indicators:

• U-factor: Indicates a window’s overall insulating value. An efficient window should be rated 3.0 or below.

• Solar heat gain co-efficient: Measures how well a window deflects incoming solar heat. An efficient window should be rated 3.0 or below.

• Design pressure rating: The design pressure rating represents how well the window drains water and how strong the window frame is. You want a window with a design pressure rating between 35 and 45. The higher the number, the better the frame, the more rain drainage it can withstand, and the more wind pressure it can endure.

Although replacing windows is a relatively easy process, doing it wrong can lead to many problems, like air leakage and loss of energy efficiency.

Tips: Hiring a Window Replacement Contractor

Certain windows also come with an installation warranty, which may become void if you install the window wrong or don’t use a professional installer.

• Research products: Because many contractors specialize in one type of window, calling the right person requires making some decisions in advance. For example, if you’re looking for an energy-efficient window, you might choose to install either a PVC or a fiberglass window. Knowing what you want in advance will better prepare you to ask the right questions to the contractor – and could save you a lot of headaches and money.

• Get at least three detailed bids: The bids you receive should be more than just prices. Ideally, a bid should also specify what materials and products the contractor will use as well as what materials and labor are included – or not included – in the price. The bid should also specify start and finish dates. Always remember that the more specific the bid is the better. This will prevent issues from arising later. Ask for the bid to include payment terms as well. You should never pay the entire amount up front, no matter how much of a discount you’re offered for doing so. A good bid and contract should ask for only 20 to 30 percent at the start of the job, with the rest being paid along the way or immediately after the job is finished.

• Peruse the fine print: If there’s a problem with your home’s windows or the installation workmanship a few years down the line, you want to make sure you’re covered under the warranty. Does the warranty cover the window only or also the installation?

• Verify references: When it comes to references, you should check not only the contractor’s, but also the manufacturer’s. You want a company with a good reputation as a window product supplier. You should ask the company how long they’ve been in business

• Always check the contractor’s license: Before you start your project, you’ll want to know if your local jurisdiction requires a permit or that the contractor be registered to complete the work.

• Installation counts: Bad installation can compromise the effectiveness of even the best windows. Be sure the windows are installed according to manufacturer’s instructions, otherwise, your warranty may be void.

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