5 Mistakes to Avoid when Installing Replacement Storm Windows

person applying caulk to the inside of a window frame

Replacement storm windows are ideal for maintaining the temperature of the room inside. Particularly popular in colder climates, storm windows are perfect for replacing your old windows if you can’t afford the cost. Moreover, they are effective in reducing heating and cooling costs. Besides, if you are handy with tools, installing a storm window is less than half a day’s work. Also, if your house is an old structure, then storm windows are imperative because they can effectively prevent water from seeping into the structure of your home. Storm windows are also quite effective in stopping air infiltration into the room.

While installing a storm window may seem like an attractive option, there are a few mistakes that you must avoid when installing them. Here are five of the most common mistakes made when installing replacement storm windows.

1. Poor Fitting

Check the fit of the storm window. You have to be precise and thorough when you take measurements. If you don’t take at least three measurements of each window's width and height, you can end up with the wrong fit. You will find that each time you measure, there is a minimal change in the measurement. You then have to take the smallest of the three measurements.

A common mistake is to measure the frame and get a storm window of the same measurement. Also, you should subtract at least ¼ of an inch from your measurements. This is because if the storm window fit is a tad smaller, you can always shim or caulk to fill the gaps; however, if the storm window is larger than the frame, it will be a considerable waste of time and money.

2. Avoid the Use of Silicone

When attaching your storm window's fins, use an elastomeric caulk or even butyl; do not use silicone at any cost as it will complicate any future repairs and/or replacements of the window.

3. Proper Caulk Application

When applying caulk to the storm window, ensure that you apply it first to the side and then to the top of the window. It is best to take a little at a time and distribute it evenly as you move along; this is because lumpy or uneven caulk can affect your window's alignment. Also, avoid applying caulk to the bottom of the window until after you've fitted and fastened the storm window.

4. Leaving Some Gaps

When fitting the storm window, you need to press it into the window opening, ensuring that it centers between the window's side stops. It is common to fit the storm window in tightly between the casing and the windowsill; however, leave a small gap at the top. This is to allow the casing some space to expand when temperatures change.

5. Don’t Caulk the Ventilation Holes

Lastly, once the window is fastened, you will most likely apply caulk to the window's bottom edge and fill up any gaps. However, you will notice that your storm window has a couple of small holes at the bottom. Ensure that you do not apply caulk and fill them because they provide the much-needed ventilation to avoid condensation.