Replace Windows Without Breaking the Bank or the Wall 2026

Replacing old windows doesn't necessarily mean you have to tear into the masonry. Instead of removing the old frame, you can cover it with a new one, avoiding unexpected surprises and costly renovations. This method, often called "overlapping frames," uses a covering fin between 3 and 10 cm and a useful depth of 5 cm to hide the old frame. The result is a faster installation, less disruption to your daily life, clear upfront costs from your installer, and plenty of natural light thanks to the slim profile of the new frame.

If you find cracks or loose anchoring between the frame and the wall, you can inject polyurethane foam for a proper thermal break. Once it hardens, simply trim the excess flush with a sharp blade. Special trim pieces cover any remaining gaps on both the exterior and interior sides of the window. No visible screws are used, and the final result is an excellent solution both in quality and appearance. The installer removes the old window sashes and mounts the new, custom-sized one with simple operations, making adjustments a breeze. When choosing your new windows, you have many options, but aluminum frames offer excellent draft protection thanks to special gaskets on the seals.

Why Glass Matters Most

But it's through the glass that you lose the most energy if it doesn't match the quality of the frame. The glass surface area is far larger than the frame itself. Double-glazed windows are now pre-assembled into a single sealed unit, inside which an inert gas is injected. This allows for significant energy savings and, by replacing the air, prevents condensation from forming inside the panes.

These upgrades guarantee significant financial savings, which can be even greater if you qualify for tax deductions at the time of the work. To maximize your home's efficiency, consider pairing your new windows with energy-efficient curtains or smart lighting to further reduce your energy bills.

Frame Installation Step-by-Step

Preparation

• Remove the sashes from the old window frame.
• Take off the hinges and any other parts that would block the new U-shaped cover frame from being inserted.

Securing the Frame

• Insert small shims into any empty spaces between the wall and the new cover frame to prevent movement or warping.
• If small shims aren't enough or are difficult to insert, use mounting foam for a secure fit.

Finishing Touches

• Finish the gaps on the exterior side with silicone sealant to ensure a watertight seal.
• For the interior, you can add decorative trim or mirrors to enhance the room's brightness and style.

Frequently Asked Questions

Can I install new windows over old ones in any type of home?

Yes, this method works well for most homes, especially where the existing frame is still structurally sound. It's a popular choice for apartments and older buildings where preserving the exterior facade is important. If you're also updating your outdoor patio furniture or garden supplies, consider coordinating the style of your new windows with your outdoor space.

How much energy can I save with new double-glazed windows?

Depending on your current windows, you can save up to 30% on heating and cooling costs. The inert gas filling and thermal break technology significantly reduce heat transfer. For even greater efficiency, pair your new windows with insulating rugs and thermal curtains.

Will overlapping frames reduce my window size and natural light?

Minimally. The new frame only adds a few centimeters, so you'll still enjoy plenty of natural light. To make the most of it, place mirrors opposite the windows to reflect light deeper into the room.

Do I need special tools or skills for this project?

While a handy DIYer can manage the installation, it's often best left to a professional to ensure proper sealing and alignment. However, you can prepare by clearing the area and having basic tools like a level, shims, and sealant on hand.

Can I combine window replacement with other home improvements?

Absolutely! Many homeowners use this opportunity to update their lighting fixtures, install new wall decor, or even replace their beds and mattresses for a complete home refresh. It's also a great time to consider outdoor decor like pergolas or gazebos to create a seamless indoor-outdoor living experience.