Renovating a Toronto Home for Multigenerational Living: Two Homes for One Family
An existing family home can become the starting point for a very different housing arrangement when the needs of one generation begin to overlap with those of the next.
In this scenario, a mother remained in the house she had owned with her husband. After his passing, she, her son and daughter-in-law decided to adapt the property so that the young family could move in while she could continue living independently on the same site.
Rather than selling the house and finding two separate properties, the family fully gutted and modernized the existing home, enlarged it, and added a new side addition containing a separate residence for the mother.
The result is a multigenerational home built around proximity and independence: the young family occupies the main house, while the mother has a complete two-level home of her own.
A Multigenerational Renovation Rather Than Two Separate Moves
The starting point is different from a new multiplex development. The family already owns the land and the existing house, so there is no property acquisition cost to add to the construction budget.
That existing equity can be directed toward the renovation and addition instead. The project also allows the mother to remain on a familiar property while creating enough space for the next generation to establish its own household.
The house is fully updated rather than simply divided. Existing systems, finishes and layouts are renewed, and the building is enlarged to provide two residences that can function independently.
The Mother’s Home Is a Complete Two-Level Residence
The new side addition contains approximately 1,230 sq. ft. of finished living space for the mother.
The main level is organized as an open living, dining and kitchen area with a balcony. The lower level contains two bedrooms and a bathroom.
Because of the property’s topography, the lower level is a full South-facing walkout with an abundance of natural light. This gives the bedrooms a direct relationship to grade and allows the lower floor to function as part of the everyday living space.
The Main House Grows With the Young Family
The renovated main residence contains approximately 3,470 sq. ft., including its finished lower level.
For the son, his wife and their young family, the project provides the space and contemporary building systems of a substantially renewed home without requiring the family property to be sold.
The design challenge is therefore broader than adding a secondary suite. The work needs to resolve the existing house, the new family program and the mother’s residence as one coherent project.
What Could a Project Like This Cost?
The two residences contain approximately 4,700 sq. ft. of finished area in total.
At an illustrative hard construction cost of approximately $320 per sq. ft., the renovation and additions produce a hard construction budget of approximately $1.504 million.
Because the property is already owned by the family, no land purchase is included in this example.
Add approximately:
- $185,000 for design, engineering, permits, municipal costs, legal work and other soft costs
- $60,000 for financing and carrying costs
- $120,320 recommended construction contingency, equal to 8% of the hard construction cost
The resulting project budget is approximately $1.749 million, or about $372 per sq. ft. of finished residential area, excluding the value of the existing property and the recommended contingency. The recommended contingency is 8% of the hard construction cost, or approximately $120,320.
| Project Cost | Illustrative Amount |
|---|---|
| Land purchase | Not required – existing family property |
| Hard construction | $1,504,000 |
| Soft costs | $185,000 |
| Financing and carrying costs | $60,000 |
| Total Project Cost | $1,749,000 |
| Recommended contingency | $120,320 (8% of hard cost; excluded from base budget) |
The Existing Property Changes the Financial Equation
The family already owns the house and land, so there is no property acquisition cost.
That does not make the renovation inexpensive, but it changes where the family’s capital is going. Instead of purchasing a second property for the young family or a separate condominium for the mother, the investment is concentrated in one property the family already controls. Redeveloping the existing property also avoids the real estate commission associated with selling it and the land transfer tax and legal costs that would arise with the purchase of another property.
The completed project also contains two substantial homes. The value is therefore not limited to the renovation of the original house; the work creates an additional independent residence and extends the usefulness of the property across generations.
Independence Matters as Much as Proximity
Multigenerational living works differently when each household has a home of its own.
The mother can live close to her son, daughter-in-law and grandchildren without sharing their kitchen, living room or daily routines. The young family gains the practical advantages of having a parent nearby without either household giving up its independence.
Separate living spaces can also make the arrangement more durable. Family needs will change, children will grow, and the amount of support the mother needs may change over time. A complete secondary residence provides more flexibility than a bedroom or small in-law suite incorporated into the main house.
Accessibility Can Be Planned Before It Is Urgently Needed
The mother’s unit illustrates another advantage of planning the arrangement as part of a major renovation.
Future accessibility needs can be considered while an addition is being designed. At Haus L1, wider doors and provision for a future stair lift support adaptability. The home does not have step-free access: the route from the street still includes one step, and a stair lift has not been installed.
For other projects, measures such as reduced thresholds, blocking for future grab bars, circulation clearances or lift provision should be assessed against the occupant’s needs and the site’s access constraints. These measures should be described separately from a claim of step-free access.
The appropriate measures depend on the occupant and the building, but it is generally easier to provide for future adaptability while the structure is already being substantially altered.
One Property Can Support Different Stages of Family Life
The arrangement does not have to remain unchanged forever.
The mother’s residence may serve her for many years. At another stage, it could potentially accommodate another family member, a caregiver or a different household.
The main value of the arrangement is that the family has created options within a property it already owns. The building can respond to changing household needs without requiring every change in family circumstances to trigger a move.
The Design Still Begins With the Property
Not every existing house is equally suited to this approach.
Lot width, setbacks, existing structure, grading, mature trees, servicing, parking, construction access and zoning can determine where an additional residence can be located and how independently it can function.
Topography can be an asset. In this example, the grade allows the lower level of the residences to walk directly out to the exterior.
Early feasibility should therefore test the existing house and site before the family commits to a particular arrangement.
Test the Multigenerational Strategy Before Design Begins
For a multigenerational renovation, the early questions are both architectural and financial.
How much of the existing house should be retained? Where can the secondary residence fit? How large should each home be? How independent should the two households be? What accessibility provisions should be incorporated now? And does the resulting construction budget make sense compared with the family’s alternatives?
Our Pre-Design Study can test the existing property, zoning, building area, massing, site constraints, preliminary construction budget and likely approval path before the full design process begins.
For more information about related work, see our Renovation and Addition Design in Toronto, Multiplex Design in Toronto and Pre-Design Study pages.
See the completed two-home project
Haus L1 creates two homes for two generations. Wider doors and preparation for a future stair lift support adaptability, but street access still involves one step. The completed project is distinct from the illustrative budget in this article.