There are so many options to consider when buying new glass for your residential windows. Different types of glass perform differently and affect the climate in your home in different ways. Plus, you need to think about the direction the windows face. You may need different types of glass on different sides of your house. Here's a look at some possible options.
North windows usually get the least amount of sun, so this is a good side for installing less expensive glass to save money. North windows are great for letting in natural light, but the UV rays are not as strong here so you don't have to worry as much about solar heating through the glass. However, you still want frames that are well-insulated, and you may also want double or triple panes just like the rest of your home to keep out cold weather. You can look for ratings on the glass for air leakage, which lets you know how well the glass insulates, and visible transmittance, which lets you know how much light the windows will allow in the room. The north side is a good place to install windows with higher visible transmittance.
South And West Windows
South windows generally receive most of the sun. Windows that face west also receive a lot of sun in the long summer months. These areas of the home need special consideration when choosing window glass. If keeping heat outside is your main goal, then you'll want glass that reflects the sun so solar heating is reduced. If you don't have shade near the windows, you may even want tinting that reduces glare so you can look out the windows comfortably.
If you want to use the sun to help keep those south-facing rooms warm in the winter, then you'll want glass that lets in more heat and sun. In that case, look for glass with a higher solar heat gain coefficient, or SHGC. Window glass has ratings on the label and the SHGC lets you know how much sunlight filters through the glass to be used as solar heating. If you want the extra heat, choose glass with a high SHGC and if you want less heat from the sun, choose glass with a low SHGC rating.
East windows let natural light stream through, and in the mornings, they can let in quite a bit of sunlight. Solar heating isn't as much of a problem with east windows because the sun isn't as strong early in the morning and it doesn't shine through the glass for very long. However, you might have to deal with glare that interferes with watching TV or working on a computer. Consider treating east windows to reduce glare so you can leave the blinds open and enjoy all the natural light the windows provide. Just like the other windows, you'll want frames and glass that are well-insulated so there is minimal heat transfer through the glass. The U-factor rating reflects how much heat transfers through glass. The lower the rating, the better heat is kept from moving through the glass so warm air stays inside in cold weather and outside in hot weather.
When you shop for new windows, just look for the ratings label on the glass. This label can help you choose the ideal glass that helps you achieve your goal of letting sunlight in or keeping it out. Plus, it will help you understand how well the glass insulates. This along with guidance from a professional can help you choose the best glass for your new windows.