Basement Excavation Project: Creating Extra Living Space

By Editorial Team

Updated on October 31, 2025

Digging out a basement is a complex building project that leaves no place for improvisation. The slightest error could cause the house to collapse. It is a delicate process, especially if the house contains walls that are shared with other buildings.

Any damage caused to neighbouring houses would fall under the owner’s responsibility. However, in a lot of cases, it can turn out to be worth it, as it will create an extra living space.

Get Your Project Started Today

Submit your details and receive up to 3 FREE QUOTES from trusted contractors.

Checking the feasibility of the basement excavation project

The cost, the amount of risk involved and the general feasibility of the project vary depending on several factors. In all cases, you’ll have to contact a professional who will determine if the project is doable and will be able to select the adequate methods to carry it out.

Don’t forget to make sure that your new space will satisfy the requirements in terms of natural light sources that are mentioned in the National Building Code. Also, check the height of the municipal sewers to make sure that the basement drain will be able to function properly.

Contacting a qualified professional to determine the work that needs to be done

Your excavation expert will adapt his methods according to the current foundation’s structure, its location, the possible presence of groundwater, as well as the quality and type of soil that they will have to work with. This step is crucial as it is then and there that you will be able to determine whether or not the basement excavation process is possible. If the project is deemed feasible, the expert will examine the foundation closely and make a plan for the following steps.

Digging out a basement that already exists

Digging out a pre-existing basement is a great option for people looking to increase the amount of livable space in their home. Older houses often have crawl spaces or partial basements which aren’t big enough to use as rooms. In these cases, excavation work can be carried out by lowering the ground level. The cost for this type of project is generally lower than that of creating an extension.

Working with an excavation company

Needless to say, this type of renovation project MUST be done by a professional, who will be able to guarantee that the foundations will not be made more fragile. They will calculate the new structure’s resistance level, as well as determine which steps will be necessary to avoid causing problems with the building’s structure. 

Among other things, they will recommend installing new foundation walls below the house to create a better weight distribution, in addition to making it possible to build a space that is the same size as the ground floor.

They will also advise that you cover the basement walls using a special membrane that drains the walls, preventing future water ingress situations. Increasing the size of your house works on two levels: you’re creating more living space whilst adding extra value to your house, which will be reflected in the sales price.


Get 3 free quotes for your project!

Submit a project and get 3 free quotes!

Looking for something else?

Table of contents

3 min read

Find contractors near you

Enter your postal code



Related articles

The latest industry news, interviews, technologies, and resources.

10 min read

Editorial Team

21 Jan 2025

Lifting or Raising a House - Key Insights for Success

Renovating a house is an essential step for preserving and increasing property value while ensuring the safety and comfort of occupants. Amongst large-scale renovation projects, lifting or raising a house is highlighted by its numerous upsides, whether done as a flood prevention measure, to increase the dwelling’s square footage, or to fix structural problems. Albeit this technical process may seem complex, with proper preparation and the right professionals, it makes for a durable and advantageous solution. 

Basement
5 min read

Editorial Team

08 Nov 2023

When Should You Replace a French Drain?

Depending on the circumstances of its installation, a French drain (or foundation drain) has a decent service life before it needs to be changed. You may be wondering if and when your drainage system needs to be replaced—check out this article for all the answers you're looking for!

Basement
16 min read

Cynthia Pigeon

07 Jul 2026

Home Wind Turbines: Clean Energy for All

Locally generated clean energy—that’s the promise of a home wind turbine. But do you need a permit to install one? Is it financially worthwhile? Here are the answers to all your questions about this technology.

6 min read

Amanda Harvey

03 Nov 2025

Maintenance Tips for Bathroom Tiles

Tiles come in all kinds of colours, shapes and sizes, keeping bathroom floors waterproof and beautiful. However, like any home surface, they need proper maintenance to uphold their elegance while preventing cracking, mould or mildew growth.

Bathroom
4 min read

Cynthia Pigeon

08 Nov 2023

How to Dismantle a Cast Iron Tub

Cast iron tubs are not lacking in the charm department and, as an added bonus, they are extremely durable. However, they will eventually need to be replaced or simply removed. Since these tubs are very sturdy, they can be quite complicated to dismantle, given that they are generally very heavy and firmly built.

Interior renovations