Home additions
Adding to a house you already like, rather than buying one you like less. The hardest half of this job happens before anything is built.
An addition is the job where the municipality has the most say and the homeowner has the least warning about it. Everything structural is straightforward by comparison: the risk lives in zoning, in setbacks, in lot coverage, and in whether the thing you want is permitted as of right or needs a minor variance.
If it needs a variance, it goes to the Committee of Adjustment, which is an independent body appointed by council and sits on its own calendar. No builder controls that date. We tell you at feasibility whether your addition is likely to need one, because it is the single largest schedule risk on the job and finding out in month four is how a project loses a construction season.
The scope
- Zoning and feasibilityWhat the lot allows as of right, and what would need a variance. Before you commit to a design.
- Conservation authority reviewWhere the property sits near a valley, a watercourse or a regulated area, which is common across the northern GTA.
- Design and permit drawingsIncluding the structural design, sealed by a professional engineer where the work calls for one.
- Committee of AdjustmentPreparing the application and the drawings that go with it, and the notice requirements.
- Excavation, footings and structureUnderpinning where the existing foundation needs to go deeper, and the pre-condition survey of neighbouring property that goes with it.
- Tie-inRoof, envelope, mechanical and finishes joined to the existing house so the join does not announce itself.
The sequence
- Zoning review and feasibility
- 2 to 4 weeks
- Design and structural drawings
- 8 to 14 weeks
- Committee of Adjustment, if required
- Set by the municipality
- Permit review
- Set by the municipality
- Excavation and foundation
- 3 to 6 weeks
- Framing, roof and envelope
- 4 to 10 weeks
- Rough-ins, inspections and finishes
- 12 to 20 weeks
A rear addition that is permitted as of right is a very different programme from one that needs a variance. Treat those as two projects with two timelines, and ask any firm you are considering which one yours is before you get attached to a drawing.
What it costs, and what moves it
Additions carry costs a renovation does not: survey, structural engineering, the variance application if you need one, excavation, and often underpinning where the new foundation has to meet the old one. Those land early and they are spent whether or not the addition proceeds.
Underpinning next to a neighbour carries the most risk on this kind of job. A pre-condition survey of the adjoining property before work starts is cheap, and it is the best evidence there is when an argument starts about a crack that may have been there for a decade.
What to ask, whoever you hire
Take this list to us and to everyone else you are considering. The answers are more useful than the portfolios.
- Does this addition comply as of right, or does it need a minor variance?
- Is the property inside a conservation authority regulated area?
- Who seals the structural drawings, and is the engineer inside your price?
- Is a pre-condition survey of the neighbouring property included before underpinning?
- What is the plan if the Committee of Adjustment refuses or defers?
- Does anything here create a second dwelling unit or change the use, which is what brings development charges into play?
Projects
Questions we get on this
- Do I need a minor variance for a home addition?
- Only if the addition does not comply with the zoning by-law on setbacks, height, lot coverage or floor space index. If it does not, the application goes to the Committee of Adjustment, whose hearing dates are set by the municipality and not by your builder. Find out at feasibility, because it can add months.
- What does a home addition cost in the GTA?
- An addition costs more per square foot than renovating existing space, because you are paying for excavation, foundation, structure, envelope and roof before you reach anything you can see. Add survey, structural engineering and the variance application, all of which are spent before construction begins.
- What happens if underpinning damages my neighbour’s foundation?
- The pre-condition survey described above is what decides it, because it establishes with photographs and dates what was already cracked, settled or out of level before anyone dug. Ask, before the excavator arrives, who carries the liability insurance on the underpinning and what the limit is. Ask also whether the neighbour has been given notice in writing.
Further reading
- Underpinning a Toronto basement, and whether you actually need itWhat underpinning is, what benching is, the ceiling height that makes the whole thing worth doing, and the honest test for whether the basement you have is already good enough.
- Do you need a permit for that? A Markham renovation guideThe principle is simple. Work that changes structure or alters electrical, plumbing, or mechanical systems generally needs a permit. Cosmetic work generally does not. Here is where the line actually falls.
- How long a whole-home renovation actually takesConstruction is the part you can see. The schedule is usually decided months earlier, by drawings, approvals and one cabinet order. Here is what actually moves the clock.
The rest of the work
- RenovationOne contract covers the drawings, the permits, the construction and the cabinetry, for a kitchen, a main floor or the whole house.
- Custom homesA house drawn from the lot up and built by the people who drew it. One contract from the first sketch to the day the keys work.
- Interior designWe draw rooms to be lived in for twenty years. We choose and name every surface before a wall moves, and we document it well enough that nobody on site has to guess.
- MillworkWe cut cabinetry for the room it goes in, from the drawings we made of that room. Rift oak, fluted bases, unlacquered brass.