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How to install an aluminum window: your comprehensive guide

Choosing aluminum windows is an excellent way to improve your home’s energy efficiency as well as its esthetic appeal—not to mention, these windows offer impressive durability, up to and even exceeding 60 years.  

Today, we’re going to guide you through all the steps required to install an aluminum window, from preparing the opening to making the final adjustments.  


The installation process for an aluminum window, step by step 


Installing an aluminum window is a process requiring precision and attention. Here are detailed instructions in six key steps to install an aluminum window yourself: 

  1. Prepare the opening 

  • Measure the opening: Make sure the dimensions of the opening are correct to fit your new aluminum window. You’ll need to measure the height and width at several points to make sure the opening is uniform. The opening must be at least 1 inch wider and taller than the dimensions of the finished product. 
  • Clean the opening: Remove all debris and make sure the opening is clean and dry. 
  1. Check the window

  • Inspect the window: Before installation, inspect the window for any damage that may have occurred during shipping and handling. 
  • Measure the window: Check that the window dimensions are the right fit for the opening. 
  1. Prepare the window

  • Place shims: Place shims along the bottom of the buck (the wood framework) to support the window during installation, to ensure space for insulation and, above all, to level the window. Shims should be positioned approximately every 12 inches.  
  1. Install the window

  • Fit the window: Lift the window and fit it into the opening, making sure it is centred. 
  • Check that the window is level: Use a bubble or laser level to make sure the window is level and plumb (sitting perfectly horizontal and vertical). Adjust its position using the shims if necessary. 
  • Secure the window: Secure the window to the buck using screw appropriate to the type of buck framing material, only on the sides of the window (never on the top and bottom). Make sure you don’t over-tighten, to avoid distorting the frame. 
  1. Seal the window

  • Apply insulation: Insert wool or foam insulation between the window frame and the opening to increase energy efficiency. 
  • Seal the joint: Apply silicone sealant around the outside of the window to seal gaps and prevent water and air infiltration. 
  1. Conduct final checks

  • Do a final cleaning: Clean the window and surrounding area thoroughly, making sure to remove any paint or sealant residue.  
  • Inspect the window: Inspect the window to make sure all steps have been correctly executed and that the window works properly.  

If you follow these detailed steps, you’ll be sure that your aluminum window has been installed correctly and is secure and functional. If you have any questions, feel free to contact your GIT representative.


Why you should choose the experts at GIT to install your windows 


Aluminum window installation may seem like a simple process, but it often involves intricacies that require an expert’s eye. That’s why we highly recommend entrusting the job of installing your aluminum windows to our team. The benefits are many and clear: 

  • Certified expertise: GIT installers are certified professionals who know all the ins and outs of the products they install. This guarantees a flawless installation that will last. 
  • Precision adaptation: Every window demands a customized approach, especially in the case of complex renovations. The experts at GIT will assess and adapt the project to ensure the best possible installation. 
  • 10-year warranty on installation: With us, you’ll enjoy complete peace of mind thanks to our outstanding 10-year warranty on installation, which includes complete parts coverage as well. 

With GIT, you benefit from trouble-free installation without having to lift a finger. Here is the 6-step installation process by our experts 

  1. Measurements: A GIT technician takes care of measuring the windows you plan to replace. 
  2. Delivery: Our experts guarantee delivery of your new windows to your home on the specified date. 
  3. Removal of existing windows: Our installers carefully remove your old windows and properly dispose of them. 
  4. Installation of new windows: The team installs your new windows, ensuring they are perfectly positioned and optimally insulated.
  5. Finishing: Our installers pay particular attention to fit and finish, both exterior and interior, following your specifications for flawless results.
  6. Clean-up: After installation, our team cleans up the site, leaving it as clean as when they arrived and ensuring your comfort. 

Preparing the site for installation by GIT  

To help the work go smoothly, here are a few tips for preparing the site before our installers arrive:  

  1. Remove vehicles from your driveway. 
  2. Move furniture and accessories that are near the work area, like blinds, curtains, rugs, carpets, framed art, decorative objects and so on. 
  3. Make sure there is at least 4 feet of clearance in front of the windows to be replaced.  
  4. If need be, clear snow to ensure a pathway to your windows, including basement windows.  
  5. Remove any air conditioner units from windows to be replaced. 
  6. Remove any security bars/grates covering windows to be replaced.  
  7. If you have a pet that could run away, have someone watch it, or make sure to keep an eye on it at all times. 
  8. If need be, clear snow from paths, driveways and balconies. 
  9. Give our installers a number where they can reach you any time, if you can’t be home during the work. 


You are responsible for contacting your city to obtain a parking, sidewalk closure or alleyway closure permit, depending on the nature of the work. If the installation requires work at height using special tools, please inform your municipality of this as well, to comply with their requirements.  

You must make sure the work site is safely laid out so that we can deliver and install the products. 

Also ensure that there will be parking spaces available over a length of 65 feet in front of your property. If need be, we can lend you “no parking” signs. If you aren’t able to use your personal vehicles to block off parking spaces for us, please e-mail your request to us at 


Installing an aluminum window: last word


You now know all the steps required to install an aluminum window, whether you do it yourself or have our team of certified experts handle the job for you. If you happen to be shopping for windows right now, ask for your free estimate today!