Basement Window Cutting: A Comprehensive Guide [2024]

With the cost of housing on the rise, more and more homeowners are finding ways to renovate their current homes to create more usable living space rather than moving. One of the most cost-effective ways to do this is to finish the basement.

You can add value to your home with an extra bedroom, home office space, entertainment room or even an in-law apartment in this typically underused area below ground. While this seems like an easy enough DIY project, one of the first things you’ll need to do is add an egress window to meet building codes.

Most basements only have small windows or glass blocks for ventilation. To meet safety codes, a larger window must be installed in case of fire or other emergencies. This will require cutting the concrete foundation wall to accommodate the larger window – a highly-skilled job that should likely be left for a professional or at the very least, someone with some experience.

Preparing the Site

If you’ve got a limited budget and have general contracting knowledge, you may want to tackle some of the prep work that’s needed such as:

• Calling the utility companies to mark underground hydro, natural gas, cable and water lines. This is not only a good idea so you don’t damage these hidden lines, but it may also be a law in your province to call before doing any excavation work. Dig Safe Canada has a list of all provincial regulations to assist you.
• Establishing the dimensions for the egress window you want to use.
• Ordering the proper type and size window. There are specific requirements associated with egress windows.
• Build window framing from pressure-treated lumber.
• Possible digging out the window well area (that may be needed to comply as an escape route.)
• Installation of window well (you may need an expensive custom size.)
• Addition of flexible, PVC irrigation pipe that will allow the well to drain properly.
• Tarping the interior to protect a finished basement from water damage when cutting the concrete. Water is used to reduce friction on the cutting blades and could damage exposed items inside.

Leaving the Concrete Cutting to the Pros

While you may be tempted to try your hand at concrete cutting after watching a couple of YouTube videos, it can be extremely dangerous and expensive to do so. The level of complexity, responsibility, experience and permits required to do the job safely and correctly dictate that a professional contractor do this job.

Building codes vary for each municipality and your contractor will be familiar with permit requirements in each area. For example, Calgary building codes require a buck frame be installed when cutting a concrete foundation and enlarging a window.

Professional concrete cutters will make sure these critical elements of the job are done properly so you avoid major structural damage and/or extra expense:

• Proper opening size and location (including accommodation for the window frame.)
• The right type of egress window well is used to meet code and height requirements. It will also include proper irrigation to allow the well to drain instead of fill with water during rainstorms or snowmelt.
• All permits are in place prior to construction. This means that the specific requirements for your area are met for egress windows, concrete cutting, and any special codes related to the project.
• Window well is positioned away from the downspout to prevent flooding.
• Oversized openings are reinforced with metal bars or plates.
• Budget overview and itemized scope of work identifies any extra costs associated with special finish work, concrete pours, reinforcement, thick walls, or decorative stones.
• Breaking up the concrete and removing the pieces of the wall area to accommodate the window and frame.

In addition, concrete cutting contractors will complete the job quickly and efficiently. A pro can usually get this project done in a couple of hours including debris removal. You’ll know the job will be done with the proper equipment. You’ll be protected as they’ll be licensed and insured against any damage to your home.

Hiring a Window Installer

When you hire a window installer to handle your egress window project, you’ll be assured of getting the proper window for the specific application you’ll be using. For example, the National Building Code of Canada (NBCC) requires minimum light for the floor area, year-round mechanical ventilation and properly sized to provide sufficient height, width and area to be used as an emergency escape route.

You can choose from casement, vertical slider or horizontal slider. The contractor can explain the various efficiency options available to keep your basement area free of drafts and water infiltration. This will not only make the space more comfortable, but it will also save you money on utility bills year-round.

The installation will be done with the proper concrete tools, TapCon or Ramset nails/fasteners and hardware for a secure fit. You can expect waterproofing with caulking, flashing and concrete glue.

Interior and exterior trims, hardware and security features can be done at the time of window installation for a complete, finished product.

Hiring a professional window company will also provide you with a warranty on both materials and labour. This will cover any problems you may encounter long after the project has been finished and save you from doing the work again.

Post Installation Work

Don’t forget, unless you hire a general contractor to do the entire project, you’ll have to do a few things to wrap up the egress window job, such as:

• Backfill around the outside of the window well, tamping dirt down as you go.
• Add pea gravel inside the window well, to about 1″ below the trim. Push the drain flush with the gravel to allow water to properly clear the well through the drain tile below.
• Add about 6″ of topsoil around the outside of the well to create a slope to allow water to properly flow away from the window.
• Inside, you may need to do some finish work such as drywall (below-grade material), painting, window treatments, etc. to finish the look.

Adding an egress window to your basement will provide a cost-effective way to add more living space to your home and extra value when you sell. Don’t risk your safety and budget by trying to do the entire project yourself; hire a pro. By hiring a professional concrete cutter to do the “heavy lifting,” you’ll be assured that the job is done safely, quickly and properly for many years of enjoyment.