10 Essential Steps For A Proper Window Installation

Follow These 10 Easy Steps For A Proper Window Installation
Whether you are installing new windows yourself based on window installation guidelines or hiring a professional to do the job for you, simply knowing the basics about the window replacementprocess will save you time and money.
The window installation process is often the same for basic types of windows, such as double-hung windows, casement windows, or beautiful bay windows. Things tend to get a bit more complicated with commercial windows, but there is nothing a professional window installation company can’t handle. Here are the 10 essential steps for a proper window installation:
1. Confirming the measurements
No doubt you have heard the old adage “measure twice, cut once”. As expected, the philosophy applies to window installation as well if you want to achieve proper installation and increased energy efficiency. Prior to the installation process, you or your professional window installer should measure both the old window and new window to check for any discrepancies. Correct measurements are always part of the basics of window installation. Furthermore, accurate measurements are crucial if you want to prevent the improper installation of your windows and make the most of your energy-efficient window.
2. Removal of the existing window
Carefully remove the old window while protecting the wall and any facings or moldings, which will be reinstalled with the new window. It is generally advisable to change out the window frame at the same time an old window is replaced since old frames are often not weathertight and may lead to leaky windows and water damage. Old frames may also allow air and moisture to pass between your home and the outside environment leading to increased heating/air conditioning costs and structural damage from rotting wood.
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3. Inspection of the opening
Once the old frame is removed, check the exposed opening to ensure there is no structural damage. If structural damage is to be found, make sure you repair it prior to installing the replacement window. Bad window installation can be the direct consequence of ignored structural damage.
4. Positioning
To avoid improper window installation, always confirm the proper fit of the new window by placing it into the frame and positioning it so that the glass is as close to the exterior of the opening as possible. Correct positioning reduces potential thermal transfer and condensation and avoids drafty windows.
5. Securing
Use quality shims to make minor fit adjustments and ensure that the window sits completely square and level within the frame. A level will allow you to confirm the window corners are at a perfect 90-degree angle for proper function. Once the window is perfectly positioned, use pilot holes and screws to secure the window into the frame.
6. Insulation
Maximize the airtightness of your window by placing insulation around the frame. There are various insulation products on the market, all designed to keep the cold weather out and your energy costs to a minimum. If you are working with a professional installer, they should help you analyze your needs and choose the best insulation for your window.
7. Exterior finishing
Caulking is used to create a water tight seal between the window frame and the exterior siding of your house. Proper caulking will flex with the expansion and contraction of the building. This is achieved by a joint that is neither so small that it lacks adhesion nor so thick that it lacks flexibility.
8. Interior finishing
To create a clean, polished finished look, moldings or casings of your choice will be installed to cover the raw interior face of the window frame and window jamb.
9. Worksite cleanup
If you decided to perform your complete window replacement on your own, cleanup is on you. However, if you’re working with a professional window installation company, you should expect them to fully clean up the job site, including removing your old window.
10. Inspection and approval
Once the installation and cleanup are complete, your installer should review the finished product to ensure you are satisfied with the quality of the work and that you have all the information on proper usage and applicable warranties. Read the window manufacturer’s instructions and maintain your window properly to make the most of its features.
By following these 10 essential steps, you can look forward to a proper window installation, which maximizes thermal retention, minimizes potential moisture infiltration, contributes to low energy bills, and looks fantastic for years to come.
Post Update: The article was updated on September 15th, 2022, originally published on September 19th, 2018. It has been completely revamped and updated for accuracy and comprehensiveness.