How Much Does It Cost to Rewire a House in Guelph & the Tri-Cities?
If you live in an older home in Guelph, Kitchener, Waterloo, or Cambridge, you may be wondering about the cost to rewire a house and whether your current system is still safe.
Many homes throughout the Tri-Cities still contain outdated systems such as aluminum wiring or knob and tube wiring, both of which can raise important safety and insurance concerns. In fact, many insurance companies now require that homeowners make these updates in order keep their insurance! As electrical demands continue to grow, older systems are often no longer equipped to support modern living.
So, how much to rewire a house in Ontario? And more importantly, what does that investment look like for your specific home?
In this guide, we will break down the average cost to rewire a house, explain the options available for aluminum wiring and knob and tube wiring, and help you understand the difference between a full rewire and a partial update. Whether your home needs a complete rewire or a targeted fix, our goal is to help you make a confident, informed decision about your home’s electrical system.
What Is Electrical Rewiring?
Electrical rewiring involves replacing outdated or unsafe wiring throughout your home with modern copper wiring that meets today’s Ontario Electrical Code.
However, not every home requires a full rewire. Depending on the type and extent of the wiring issue, your project may involve a complete rewire or a more targeted update such as pigtailing aluminum connections or replacing only a section of knob and tube wiring.
A full rewiring project may include:
- Removing old wiring systems such as aluminum wiring or knob and tube wiring
- Installing new grounded copper wiring
- Replacing outlets, switches, and fixtures
- Upgrading your electrical panel if needed
- Ensuring full ESA inspection and approval
Electrical rewiring is one of the most important upgrades you can make to improve safety, reliability, and long-term performance.
Cost to Rewire a House in Guelph & the Tri-Cities
Average Cost to Rewire a House
The average cost to rewire a house in Guelph and the Tri-Cities typically ranges from:
$12,000 to $35,000+
This range reflects a variety of home sizes and project scopes. Smaller homes may fall closer to the lower end, while larger or more complex homes may exceed this range.
When considering the cost to rewire a house Ontario homeowners can expect, it is important to factor in accessibility, layout, and the type of wiring being replaced.
Cost Per Square Foot
Another way to estimate the cost to rewire a house is by square footage.
Most homeowners can expect:
$8 to $15 per square foot
This estimate helps answer common questions like how much to rewire a house or how much to replace wiring in house based on size and complexity.
Aluminum Wiring: Replacement and Pigtaiing Options
What is Aluminum Wiring?
Aluminum wiring was commonly used in homes built between 1965 and 1978. While it was once widely accepted, many homeowners now ask, is aluminum wiring safe?
The short answer is that aluminum wiring can be safe if properly maintained, but it does present higher risks compared to modern copper wiring.
Is Aluminum Wiring Safe?
Over time, aluminum wiring can expand and contract, which may loosen connections. This can lead to overheating and increase the risk of burnt receptacles and light switches, which are dangerous as they really do cause fires.
Because of this, many homeowners choose to upgrade their systems. Insurance providers may also require upgrades or remediation.
Your Two Options: Pigtailing vs. Full Rewire
When it comes to aluminum wiring, homeowners generally have two options:
Option 1: Pigtailing (The More Affordable Option)
Pigtailing involves connecting short pieces of copper wire to the existing aluminum wiring at each outlet, switch, and fixture. This is authorized by the ESA and is considered a safe remediation method.
However, it is important for homeowners to understand that pigtailing is not a fail-safe solution. Over time, pigtails can come loose or disconnect, which can once again lead to burnt plugs and switches. While pigtailing is a legitimate and approved approach, it does require ongoing monitoring.
For an average-sized home, pigtailing typically costs around:
~$5,000
Option 2: Full Rewire (The Fail-Safe Solution)
A full rewire is the only fail-safe solution for aluminum wiring. It completely removes the aluminum and replaces it with modern copper wiring, eliminating the risk entirely.
The cost to fully replace aluminum wiring typically ranges from:
$15,000 to $30,000+
The answer depends on the size of the home, accessibility, and whether additional upgrades like a panel replacement are needed.
Panel Replacements and Aluminum Wiring
Many homes with aluminum wiring also have Federal Pioneer (FPE) panels, as these panels were installed during the same era. Aluminum wiring paired with an FPE panel is a particularly bad combination. In many cases, the panel will need to be replaced as part of the rewiring or pigtailing project.
[Learn more about Federal Pioneer panels and why they may need to be replaced. (link to FPE blog post)]
Knob and Tube Wiring Replacement Cost in Ontario
What is Knob and Tube Wiring?
Knob and tube wiring is one of the oldest electrical systems still found in homes across Ontario, including Guelph, Kitchener, Waterloo, and Cambridge. It was commonly installed before the 1950s and does not include grounding, which is essential for modern safety standards.
Is Knob and Tube Wiring Safe?
Many homeowners ask, is knob and tube wiring safe?
While it was safe when originally installed, it is no longer suitable for modern electrical demands. It cannot safely support insulation and often shows signs of age-related wear.
For this reason, replacement is strongly recommended.
Full Rewire vs. Partial Replacement
It is important to understand that the scope of a knob and tube project depends on how much is present in the home:
- If your whole home contains knob and tube wiring, a full rewire is required. This is a major project that involves replacing the entire electrical system.
- If only some knob and tube wiring is found, it may be possible to rewire just that section rather than the entire home, which can significantly reduce costs.
A professional inspection will determine how much knob and tube wiring is present and what level of work is needed.
Knob and Tube Wiring Replacement Cost for Guelph, Kitchener, Waterloo, and Cambridge
The knob and tube wiring replacement cost Ontario homeowners can expect typically falls between:
$18,000 to $35,000+
This reflects the complexity of these projects, which often require full system redesign.
What to Expect During a Knob and Tube Rewire
Homeowners should be prepared for the fact that knob and tube replacement is a very messy job. Because the old wiring runs through walls and ceilings, the process involves cutting many holes in the drywall to access and remove the old system. This creates a significant amount of dust throughout the home.
After the electrical work is complete, all of those holes will need to be patched and repaired, and the affected areas will need to be repainted. It is a good idea to plan for drywall repair and painting as part of your overall project budget.
Why Knob and Tube Wiring Needs to Be Replaced
Knob and tube wiring:
- Does not support modern electrical loads
- Lacks grounding
- Cannot safely coexist with insulation
- Often requires complete replacement rather than partial upgrades
Working with professionals who specialize in knob and tube wiring services ensures the work is completed safely and in compliance with the Ontario Electrical Code.
Key Factors that Affect Electrical Rewiring Costs
Every home is different, and several factors influence the total cost of electrical rewiring.
1. Size of the Home
Larger homes require more materials and labour, increasing the overall cost to rewire a house.
2. Accessibility
Homes with unfinished basements or open attic access are easier to rewire. Limited access or finished interiors can increase labour time.
3. Electrical Panel Upgrades
Many rewiring projects include upgrading to a 200 amp panel. This can add between $3,000 and $6,000 or more.
4. Number of Circuits and Fixtures
Adding modern conveniences such as additional outlets, lighting, or dedicated circuits will increase cost but improve functionality.
5. Permits and ESA Inspections
All electrical rewiring must meet Ontario Electrical Code standards and pass ESA inspection, ensuring safety and compliance.
Most Expensive Parts of Rewiring a House
The most significant costs in a rewiring project typically include:
- Labour for running new wiring through finished walls
- Panel upgrades and service changes
- Reconfiguring circuits
- Repairing drywall or plaster
These steps are essential for a safe and long-lasting installation.
How Long Does Electrical Rewiring Take?
Most projects take:
5 to 10 business days
Larger homes or complex rewiring projects may take longer depending on accessibility and scope.
What to Expect During the Process
Electrical rewiring is an invasive process, and it is important to be prepared for what your home will look like during the project. You should expect:
- Many holes in your walls and ceilings — electricians need to access the spaces behind your drywall to run new wiring, which means cutting numerous openings throughout your home.
- A significant amount of dust — between cutting drywall and pulling old wiring, dust will spread throughout the house. Covering furniture and sealing off living areas can help.
- Power outages during the work — sections of your home will be without power at various stages as circuits are disconnected, replaced, and reconnected.
- Drywall patching and repainting afterwards — once the electrical work is complete, you will need to have all the holes patched, repaired, and repainted. Many homeowners plan for this as a separate phase of the project.
Understanding these realities upfront helps you plan ahead and avoid surprises.
Benefits of Electrical Rewiring
Upgrading your electrical system provides long-term benefits that go beyond safety.
Improved Safety
Replacing outdated wiring reduces fire risk and ensures compliance with modern standards.
Increased Capacity
A rewired home can support modern appliances, EV chargers, and smart home systems.
Higher Property Value
Updated electrical systems are a strong selling point and can increase home value.
Insurance Compliance
Replacing aluminum wiring or knob and tube wiring often helps meet insurance requirements.
Signs You May Need Electrical Rewiring
You may need to consider electrical rewiring if you notice:
- Flickering lights
- Frequent breaker trips
- Warm outlets
- Two-prong outlets
- Aluminum wiring or knob and tube wiring is present
- Burning smells
If you experience any of these, a professional inspection is recommended.
Why Work With Blais Electric?
At Blais Electric, we understand that electrical rewiring is a significant investment. Our goal is to provide clear guidance, safe solutions, and a smooth experience from start to finish.
We focus on:
- Clear communication
- Code-compliant installations
- Respect for your home
- Reliable, long-term solutions
We proudly provide trusted electrical rewiring services across Guelph, Kitchener, Waterloo, and Cambridge.
Final Thoughts
Understanding the cost to rewire a house Ontario homeowners face is an important first step in planning your project.
Most homes in Guelph and the Tri-Cities fall between $12,000 and $35,000 or more depending on size and complexity.
Whether you are pigtailing aluminum connections, fully replacing aluminum wiring, or calculating the cost to replace knob and tube wiring, investing in the right solution ensures your home is safe, efficient, and ready for the future.
