blog-banner

Are you looking for a contractor?

Submit our quick form and get quotes now!

Table of Contents

Cost of Excavating a Crawl Space

Cost of Excavating a Crawl Space

Interior renovationsCost of Excavating a Crawl Space

In the past, concrete, rigid insulation, and waterproofing systems were largely underdeveloped. Consequently, houses couldn't be built directly on the ground. Therefore, to protect homes from water infiltration and excess humidity, they were built over crawl spaces. However, with today's building materials and techniques, having this type of feature built is no longer necessary. Moreover, crawl spaces are notorious for their drawbacks, rather than for their advantages.

A crawl space is a confined space anywhere between 30 and 60 cm high. Note that the primary purpose of a crawl space is to provide access to a home’s plumbing system. And, with home prices having significantly increased over the past few years, homeowners are eager to excavate their crawl spaces to enhance the square footage of their homes.

Why Excavate a Crawl Space?

Source : Canva

To avoid moving

In some heavily populated neighbourhoods, especially in Montréal, it's impossible to expand your home by adding an extension. The only option to increase the size of your property without having to move is to build an extension from the bottom up.

To increase the value of your property

In some areas, housing prices have literally exploded. Naturally, when it comes to selling, homeowners want to get the most out of the sale. Excavating the crawl space is the best way to increase the value of your home.

To enhance the state of your house

If your home is old and has structural or foundation problems, excavating the crawl space can increase its durability. Such a renovation project would restore the lower portion of the property while improving its stability.

To add space

Since the crawl space is a confined, restricted space, extending the space for storage purposes can be a good idea. As a result, some homeowners decide to convert their crawl space into a cellar. This project is much simpler than transforming it into a living space because the current standards are easier to meet than those for a furnished basement.

Excavating a Crawl Space: Regulations

vide sanitaire de l'extérieur_Quel prix pour une excavation de vide sanitaire?

Excavating a crawl space involves underpinning work. As such, it's imperative to check the regulations set forth by your municipality prior to undertaking any work. In addition, certain restrictions can be imposed depending on the type of work you plan on executing.

For instance, if you're furnishing a basement, you’ll have to account your an emergency exit. If you're planning to convert it into a living space, you'll need to allow for natural lighting (windows), which must amount to 5% of the room's surface area when it comes to bedrooms and 10% for dining or living rooms.

10-Step Guide to Excavating a Crawl Space

Source : Canva

1. Get an excavation permit from the city

2. Hire a structural engineer to assess the feasibility of the project

First, the structural engineer will ensure that your renovation project meets current regulations. They'll also analyze several elements, including the property's soil and the structural condition of the house, before providing you plans and a cost estimate for the excavation. Then, the renovation process can begin!

3. Knock down one of the foundation walls

4. Dig to the required underpinning depth

5. Set up steel piles to support the structure

6. Remove the excavated soil and dump it outside the space

7. Install wooden formwork

8. Build a new concrete foundation

9. Waterproof the new foundation and dig a drainage trench

10. Pour concrete on the new slab and proceed with the finishing work

Cost of Excavating a Crawl Space

Source : Canva

Excavating a crawl space requires underpinning work, which is a risky renovation technique, both for the house and the on-site workforce. Several factors impact the price of a crawl space excavation, including the condition of the house, the type of soil, the area to be excavated, etc.

Basement excavation prices range from $50,000 to $150,000. However, in some cases, this type of project can be even more expensive. For instance, take the Plateau Mont-Royal area, where most houses are built on a stone foundation with a crawl space. 

If you're planning to excavate your crawl space to expand your home, shop around prices among contractors to get the best value for your money. You'll find that quotes vary widely, and significant savings are to be had.

Are you planning a basement renovation project? We've put together a handy checklist to help you manage the various stages of the project. Click here to check it out and bookmark it! 

Cover photo: Systèmes Sous-sol Québec 

Photos: Deposit Photo

Get 3 quotes for your renovation project

RenoQuotes.com can help you get quotes from a general contractor. By submitting your project, we’ll put you in contact with top-rated contractors. Fill in the form on the homepage (it only takes a few minutes) and get estimates from trusted professionals.

Dial 1-844 828-1588 to speak with one of our customer service representatives.

Get 3 free quotes for your project!

Submit a project and get 3 free quotes!


Last modified 2024-05-17

List of sources


Get 3 free quotes for your project!

Submit a project and get 3 free quotes!

Looking for something else?


Table of contents


Get 3 free quotes for your project!

Submit a project and get 3 free quotes!

Are you a contractor?

Join our network and receive real leads!

Download the price guide for renovations

We’ll be emailing you the latest market price guide for renovations.



Related articles

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

6 min read

N/A • 08 May 2024

The cost of demolition projects

It might take years to find your dream home, especially as neighbourhoods continue to develop and are becoming overcrowded. Maybe you’ve found the perfect spot, but the house itself isn’t quite what you’d envisioned. Have you considered demolishing it? Demolishing whole homes or parts of its interior would allow you to take the land that you want and build upon it your dream home. Of course, these projects come at a cost...so what is it?

5 min read

N/A • 07 Nov 2023

Hickory hardwood floors: installation and maintenance advice

Is a new floor on your to-do list for future renovation projects? A hickory hardwood floor may be the perfect choice for your next project!

5 min read

RenoQuotes.com • 07 Nov 2023

The Different Types of Patio Doors

Has the time come to change your patio door? Given that you will have to live with it for many years to come, you definitely do not want to regret your choice.

2 min read

Léa Plourde-Archer • 08 Jan 2024

2024 Kitchen Renovation Price Guide

Are you in the process of renovating your kitchen? This list, combing the main characteristics and prices of all the important elements, is meant to help you plan out your project and choose things that are suited to your budget.

7 min read

RenoQuotes.com • 12 Jan 2024

The Multifaceted Benefits of Window Washing—It’s Beyond Aesthetics!

Have you ever considered having your windows professionally cleaned, but aren’t seeing the benefits related to this practice? One might be tempted to think that washing windows is purely done for aesthetic purposes, but think again! In fact, having clean windows, inside and out, contributes to a healthier lifestyle and elevates the look of your home as a whole. 


Looking for a contractor?

Submit a project and get 3 free quotes now!