Let's say you're tired of those old wood windows, and you decide it's time to upgrade to vinyl replacement windows. You get 2 or 3 contractors to come out and give you an estimate. After they leave, you can't believe windows can cost so much. I mean, having to get financing to replace your windows just doesn't seem right. Let me explain to you why the windows are so expensive. You have to pay the salary of the salesman who comes over to give you your "free" estimate. Then, you have to pay the salary of the installers. Finally, you have to pay the owner of the company. In some cases there is a broker who acts as a middleman, and he or she gets a cut too. No wonder you need financing! Now, imagine if you already knew how to shop for windows, how to measure for new windows, how to remove the old windows, and how to install the new windows. You just eliminated everybody except the owner. All of a sudden you can afford to replace your windows without taking out a loan! The next few articles are going to cover this process. This article is going to discuss the proper way to measure for your double hung replacement windows.
It's important to properly measure for your windows. If you order them too small, you're going to end up having to improvise in order to get them to work. Even if you do get them to work, you're probably going to have problems. And if you order them too big, you're really in trouble. Chances are you will be ordering more windows. So, measuring is very important. Fortunately, it's also very simple. We are dealing with old double hung wood windows here, so if that doesn't apply to you, don't worry. Future articles will discuss other types of windows. In the case of the wood sash windows, you want to measure the width first, and height second. When you go shopping for windows, always give the dimensions as WIDTH X HEIGHT. To measure your width, you want to pull a tape measure from the top right corner to the top left corner. Put the tape measure in that 1 1/2" pocket where the window frame slides. Measure to the sixteenth of an inch. Do the same thing at about the midway point,right above where the window locks. Then, raise the bottom sash and take the same measurement at the bottom. If you can't raise the window for whatever reason, go outside and measure from there. You will have to remove the screen though. The majority of the time all three of those measurements will be the same. If they're not the same, use the SMALLEST measurement. Now subtract 1/4" from that measurement. This is your width for the new window. The height is a bit tricky. If your window sill outside slopes downward for water drainage, you have to make sure that you measure from the HIGHEST Point of the sill. You want to measure from the top right corner to the bottom right corner. Put your tape at the top where the upper sash closes. If the bottom has a 5/8" high inside wood sill piece to prevent water from coming inside, you need to raise the bottom sash and run the tape past the 5/8" sill and down to the high point of the sloped sill. Do this in the middle and on the left. Once again, take the smallest measurement, but this time deduct 3/16". This is your height. If you order your windows using these dimensions,they will fit right in, and leave just enough room to adjust if needed. The final step is to measure the depth of the pocket where both sashes slide. By depth, I mean from the point outside where the top sash rests against the outside wood stop to the point inside where the inside bottom sash rests against the inside stop. This measurement should be between 3 1/4"- 3 1/2". The reason you need to know this dimension is because not all replacement windows have a 3 1/4" depth frame. You want a replacement window that's going to fit right into the existing pocket of the wood frame. If you purchase a window with a 2 5/8" frame depth, you're going to have approximately 3/4" to fill. That means buying new wood stops for the inside of the house that are 3/4" wider than the existing stops. Get the 3 1/4" frames and save yourself a lot of extra work. Now, if you're on a really tight budget, the lower grade windows will be the 2 5/8" frame, and you will have to get the wider trim. But that's something you should weigh in your mind, whether the money saved on the lesser grade window is worth the extra expense and time of installing new stops around the inside of all your windows.
So, now you have the measurements and it's time to go shopping. What should you look for to know you're getting quality windows? A top quality double hung replacement window will have tilt-in sashes that allow you to clean the outside glass from inside the home. All double hung windows have a mechanism that keeps the window in the raised position. The better windows use a state of the art mechanism known as a constant force balance coil. All replacement windows will have double glazing, meaning there will be two panes of glass in each sash separated by a 1/2"-5/8" spacer material around the edge of the unit. A quality window will use an intercept spacer or something called a super spacer. Find out the U-Value of the window. The lower the number, the better insulating properties. You want a window with a U-Value under .40, and if you want the windows to be energy star rated, the U-Value needs to be .30 in most parts of the country. There is a special glass called LowE that will lower that U-Value number. In fact, most quality windows include LowE as standard. Those are the main things to ask about when window shopping.
On the opposite end of the quality spectrum, you can buy an economical replacement window that will not have the tilt-in feature. The mechanism that holds the window open will consist of a block and tackle assembly made up of a spring and string. Another mechanism in lower quality windows is called a spiral tube balance. These lesser grade assemblies are notorious for failing after 5-10 years. The spacer material used on lower quality windows will be aluminum or something called swiggle seal. And many times the U-Value of these lower grade windows will be up around .50. The thing to remember is that a window that uses a super spacer more than likely isn't going to use a block and tackle balance system. It would be like buying a new car with leather interior and no power window and door locks. Follow those guidelines and you will have a good idea what quality you are buying. Once you make the decision and purchase your windows, it's time to get them home and take out your old windows. In a future article, I will tell you how to remove the old wood windows.