When it comes to home improvement projects, few tasks are as intimidating—or as rewarding—as replacing windows in a brick house. Unlike wood or vinyl siding, brick doesn’t offer much flexibility, and one wrong move can mean cracked masonry or compromised structural integrity. So naturally, one might wonder: how do you replace windows in a brick house without damaging the exterior or interior?
How Do You Replace Windows in a Brick House
The process involves careful planning, proper tools, and a solid understanding of both the window unit and the brick wall that surrounds it. This guide walks you through every crucial aspect—from preparation and removal to installation and finishing—offering insights that will help you approach this task with confidence, whether you’re a seasoned DIYer or simply trying to understand the scope of a professional job.
Understanding the Nature of Brick Construction
Before you even pick up a pry bar or screwdriver, it’s essential to understand what sets brick houses apart from other construction types. Brick is strong, yes, but it’s also rigid and brittle. That means it doesn’t respond well to vibration or force. While wood siding can be trimmed, moved, or manipulated slightly during window replacement, brick is unforgiving.
Moreover, in brick construction, the window is typically set into an opening known as a rough opening, lined with either a wooden frame or a steel lintel. This frame supports the window, and the brick around it is mortared in place. In many cases, a layer of flashing or sealant protects the window from moisture intrusion.
So, replacing windows in a brick house isn’t just about swapping one frame for another—it’s a delicate dance between maintaining structural support and ensuring a water-tight seal.
Step-by-Step Overview: How Do You Replace Windows in a Brick House?
1. Evaluate the Existing Window Type
The first step is identifying the kind of window currently installed. Most windows in brick houses fall into two categories:
- Nail fin windows: Typically used in new construction and nailed into the wall framing before the brick is laid.
- Block frame (or replacement) windows: These are installed without nailing flanges and are often used for window replacements in existing structures.
Knowing which type you’re dealing with informs how you’ll approach the removal and installation process.
2. Measure Precisely—No Guesswork Allowed
Accuracy is everything. Measure the width and height of the existing window from the inside of the frame—not the trim. Record three measurements for both width and height (top, middle, bottom for width; left, center, right for height) and use the smallest measurement in each set.
This ensures your replacement window will fit snugly without needing to alter the surrounding brick.
3. Prepare the Work Area
Remove blinds, curtains, and nearby furniture. Lay down drop cloths inside and out. Protect any landscaping or exterior features near the window.
Brickwork can chip, dust can fly, and tools can slip. A prepared workspace minimizes damage and keeps things efficient.
4. Remove the Old Window Carefully
Removing the existing window involves:
- Scoring caulk lines around the window with a utility knife.
- Removing interior trim or stops (if present).
- Unscrewing or cutting fasteners securing the window to the frame.
- Extracting the window unit, carefully tilting or pulling it out from the frame.
If the window is held in with mortar or has a flange embedded behind the brick, removal becomes more complex and may require partial brick removal or specialized tools.
Important: Avoid damaging the brick or existing wood framing. If in doubt, call a professional—brick damage is not easily reversed.
5. Inspect and Repair the Opening
Once the old window is removed, inspect the opening:
- Is the wooden frame (if present) solid and rot-free?
- Are there signs of water damage, mold, or insect activity?
- Does the flashing need to be replaced?
This is your opportunity to correct any issues before installing the new unit. Install new flashing tape or a sill pan if needed to redirect moisture away from the window.
6. Install the New Window
Slide the new window into the opening and check for level and square. Use shims to adjust if necessary. Most replacement windows are secured through the sides of the frame with screws driven into the surrounding wood or masonry anchors, depending on the construction.
Seal the perimeter using high-quality, exterior-grade caulk or low-expansion spray foam to prevent air leaks.
7. Reattach Trim and Finish
Once the window is secure and sealed, reinstall any interior trim, stops, or casing. You may need to repaint or re-caulk around the interior to match your existing finishes. On the exterior, brick molding or metal capping can be added to provide a clean and weather-resistant transition between the window and the brick.
Special Considerations for Brick Houses
Lintels and Load-Bearing Walls
In many brick homes, windows are situated beneath steel or stone lintels, which distribute the weight of the bricks above the window. Disturbing a lintel or failing to support a load-bearing wall can lead to serious structural issues. Always assess whether the opening is load-bearing and proceed with caution.
Custom Sizing
Rarely do standard window sizes match the original openings in brick homes, particularly in older buildings. Custom-sized replacement windows may be required to ensure a proper fit without altering the brick.
Permits and Codes
Check your local building codes. In some areas, replacing a window—especially in a historic brick home—may require permits or special approval.
Read More : Do Command Strips Work on Brick? An In-Depth Guide to Adhesion on Masonry Surfaces
Final Thoughts: It’s All in the Planning
So, how do you replace windows in a brick house without causing costly damage or aesthetic compromise? The answer lies in meticulous planning, precise measuring, and respect for the building’s structure. Brick doesn’t allow for shortcuts, but it rewards careful craftsmanship with durability and beauty.
Whether you decide to tackle this as a DIY project or hire a professional, knowing the process—from removal to sealing—equips you to make smarter decisions that preserve your home’s value, comfort, and curb appeal.
Replacing windows in a brick house may not be the simplest upgrade, but when done correctly, it’s one of the most transformative. Energy efficiency improves. Noise reduces. The whole facade can feel refreshed, almost reborn. And all without disturbing a single beautifully laid brick more than necessary.
