Addition Capacity
Addition analysis: Moderate capacity.

How much further your lot can grow — remaining footprint, height, and GFA capacity under current zoning.

The capacity analysis below compares your existing building against the maximum permitted envelope. Rear, side, and vertical addition opportunities are identified along with program yield — what the additional area translates to in rooms and bedrooms.

Max Storeys
2storeys
Up to 8.5 m total height
Est. GCA
147
1,586 ft² across 2 floors
Remaining GFA
+639ft²
60% of envelope used
Permitted
By right
Under RS zoning
01 / Buildable Envelope

Here’s what fits on your lot.

Massing computed from setbacks, lot geometry, and zoning height limits — a conservative envelope before architectural massing optimisation.

Where you can expand.

Rear
Major
+34 ft depth available
Side
None
+2 ft width available
Vertical
1 storey addition
+11 ft height available
Expansion Magnitude
+793 ft2
Meaningful
Best strategy: Vertical Addition may offer the largest increase in usable space.

Dimensions are estimated from lot geometry, zoning setbacks, and the existing building footprint. Confirm with a survey and site-specific review before proceeding.

Vertical Addition

Build above the existing house within the permitted height envelope.

Likely Feasible
Estimated area
+569 ft2
Height left
3.3 m
Estimated number of storeys
1
Expanded kitchenFamily roomHome office

Rear Addition

Expand behind the existing rear wall while staying inside the buildable footprint.

Likely Feasible
Estimated area
+224 ft2
Rear depth
10.5 m
Footprint
21 m2
Estimated number of storeys
1
Storage or layout improvementSmall officeMudroom

Side Addition

Side-yard expansion appears narrow and likely needs design review.

Not Feasible
Available side width
0.5 m
Minimum screen is 1.2 m.
Side width
0.5 m
Footprint
2 m2
Estimated number of storeys
1
Storage or layout improvementSmall officeMudroom
Local Precedent

Projects similar to yours.

Nearby permit records within 300m and Committee of Adjustment records within 250m from the last 24 months.

93 Wiley Ave
Two-storey rear additionCancelled
75m away

Proposal for second-storey addition, interior alterations, and a new basement suite.

53 Wiley Ave
Rear addition varianceClosed
102m away

Minor variance application for a partial rear one-storey addition with deck and rear cantilevered second-storey addition.

Rear setback1.2 m reduction
Lot coverage4.5% increase
53 Wiley Ave
Interior alteration and additionPermit issued
102m away

Revision to structural work for a ground and second floor rear addition.

02 / Capacity Analysis

Existing vs. max envelope.

MetricExistingMax PermittedRemaining
Footprint474 ft²793 ft²+319 ft²
Height17 ft28 ft+11 ft (~1 storey)
GFA474 ft²1,586 ft²+1,112 ft²
Envelope Utilization
60%
Footprint
61%
Height
30%
GCA
50%
Overall
Significant capacityConsider rebuild economics

Some standards may vary depending on unit configuration, frontage conditions, window placement, and lot geometry.

02 / Estimated Buildable Area

Floor-by-floor GCA estimate.

LevelEst. GCA (m²)Est. GCA (ft²)
Ground Floor74793 ft²
Level 274793 ft²
Total Est. GCA1471,586 ft²

GCA estimates are based on the computed buildable footprint at each floor level. Actual achievable floor area depends on core / corridor placement, structural design, and final unit mix. Professional massing optimization typically improves these numbers 8–15%.

03 / Potential Layout Scenarios

Three credible programs for your lot.

Each is a starting point — a real design pass will refine unit count, mix, and circulation against site-specific constraints.

2 units
  • 620 ft2 addition
  • 1 storey
  • Lowest variance risk
  • Keeps main floor expansion simple
Best suited for

2 units
  • 1,180 ft2 addition
  • 2 storey partial scope
  • Best value balance
  • Adds bedrooms without full rebuild
Best suited for

2 units
  • 1,850 ft2 addition
  • Major structural scope
  • Highest construction cost
  • Full family-home transformation
Best suited for

04 / Constraints & Risks

What might slow you down.

01Protected private tree review may reduce the usable rear-yard footprint.
02Exact side-yard clearance should be confirmed before assuming construction access.
03A deep rear addition may trigger rear setback, depth, or angular-plane review.
04Existing structure may require underpinning, beams, or foundation upgrades.

These factors may significantly affect achievable unit count, floorplate efficiency, and overall development feasibility.

05 / Permit Requirements

What you'll file with the City.

01Current survey or site plan with building footprint and lot boundaries
02Architectural concept plans for the preferred addition strategy
03Zoning review against height, setbacks, depth, and lot coverage
04Building permit drawings and code review
05Arborist review if protected trees are within the work area

Permit and approval requirements vary depending on the final building design, unit count, parking configuration, and servicing conditions.

06 / Development Recommendation

This is a snapshot.

Let's make it real.

Proceed with an architect-led feasibility review before committing to design drawings. The best first pass is to test two options: a compliant rear addition and a rear-plus-second-storey concept. That comparison will show whether the added construction cost of vertical work is justified by the extra bedrooms and long-term value.

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LotMore provides preliminary zoning and development insights for informational purposes only. We do not guarantee accuracy or compliance with applicable by-laws, codes, or regulations. All use of this website is at your own risk. Users should consult a qualified professional before making any development or construction decisions.