What Are Lot Coverage and Floor Area?

Lot Coverage

Lot coverage refers to the percentage of a lot’s total area that is covered by buildings, measured by the building footprints (only the area they take up on the ground).

Floor Area

Floor area refers to the total usable interior space of a building across all levels. It provides a more direct measure of the actual size of a house or structure.

What Lot Coverage and Floor Area Controls Currently Exist?

Current Policy on Denman Island:

• 25% maximum lot coverage for residential lots

What options exist for controlling Lot Coverage and Floor Area?

Lot Coverage Restriction
Lot coverage limits how much of a lot can be covered by buildings and structures. It regulates only the building footprint. This tool is useful for protecting open space, limiting impervious surfaces, and maintaining Denman Island’s natural character.

Option based on review of lot coverage across the Islands Trust Area:

Lot Size	Lot Coverage	Max Footprint (m2)	Approx. House Size (GFA, 2 Storeys)
< 0.6 ha (1.5 acres)	15%	900 m²	1,800 m² (19, 375ft2)
1.2 ha (3acres)	10%	1200 m²	2400m² (25,833ft2)
5 ha (12.35 acres)	5%	2500 m²	5,000 m² (53,820 ft²)
10ha (24.70 acres)	5%	5000 m²	10,000m² (107,639ft2)
10 ha +	5%

Floor Area Restriction
Floor area limits the total interior space of a building across all floors. It directly controls the overall size of a building.

Option:

• Establish a fixed maximum floor area for the principal dwelling on all lots (e.g. 250m²/2,690 ft²)
• Note: A 250 m² home on a 0.5 acre lot uses ~6% coverage.
• Variances may be granted on a case-by-case basis, subject to review and approval by the LTC.

Alternative:

• Set grouped maximum floor areas by zoning (e.g., R1 zones allow smaller maximums than R2).
• Set grouped maximum floor areas by property size (e.g., 0–5 acres = 2,000 ft², 5–10 acres = 4,000 ft², etc.).

Recommended Approach

Staff recommends adopting a combined approach that limits both lot coverage and gross floor area, with a maximum GFA of 250 m² for principal dwellings. This strategy ensures that buildings remain appropriately sized in both footprint and overall interior space. Limiting lot coverage helps protect open space, maintain the natural character of the area, and control impervious surfaces that impact drainage and ecology. Meanwhile, a fixed GFA cap discourages oversized homes, promotes modest and attainable housing.

What is a secondary dwelling unit?

A secondary dwelling unit is a small, self-contained home with its own kitchen, bathroom, and sleeping area, located on the same property as the main house. These can include:

• Secondary suites – units inside the main house (e.g., basement or in-law suites)
• Accessory Dwelling Unit (ADU)– stand-alone units like garden suites, tiny homes on wheels, cob houses, or modular homes
• Accessory residential unit (ARU) – either a detached building or within a portion of a building, on the same lot as a non-residential principal use

 What’s currently allowed on Denman Island?

• Secondary suites are permitted in the R2 (Rural Residential), A (Agriculture), F (Forestry), and RE (Resource) zones.
• Detached secondary dwellings are allowed in the R2, RE and F zones with a Temporary Use Permit (TUP) and in the A zone outright.

Options for Supporting Secondary Dwelling Units:

1. Expand secondary suite permission
   • This would be primarily in R1 (smaller lot residential)
   • Not compatible in conservation, water zones and R4 (Denman Green)

2. Expand accessory residential unit permission

• • Residential use is currently permitted in the commercial and light industrial zones not in community zones
  • The LTC has approved draft language to permit residential in community zones

 

4. Allow an ADU or a secondary suites on eligible lots

• • Currently, only secondary suites are allowed as a principal use. This option would allow property owners to choose either type.

5. Allow secondary suites and ADU on eligible lots

• • Both a secondary suite and ADU could be permitted with conditions

6. Allow more than one ADU with a maximum combined floor area for all units in suitable areas (Flexible housing)

• • Maximum combined floor area and number of units would correspond with the size of lot for example:

Lot Size	Number of units	Maximum Combined floor area
< 0.6 ha (1.5 acres)	3	2500ft2
0.6 ha (1.5 acres – 1.2 ha (3acres)	5	3,500ft2
1.2 ha (3 acres)  – 5 ha (12.35 acres)	6	4,750 ft2
5ha (12.35 acres) – 10ha (24.70 acres)	7	7000 ft2

Introducing some or all of the options will increase housing options over the long-term and potentially enable a number of currently non conforming secondary dwelling units into legal conformity.

Each option above could be supported by the following conditions:

1. Removal of the TUP requirement for accessory dwelling units

• • This could permit secondary dwelling units outright where ADUs are permitted

2. Allow secondary suites and ADUs in suitable areas only

• • Use mapping to guide where these homes can go, avoiding sensitive areas like shorelines, steep slopes, wetlands, and areas of archeological and environmental significance (eg. not with in 200 metres from the natural boundary of the sea).
  • Preliminary mapping suggests limited areas are suitable for additional density and intensity of land use.

3. Zoning Requirements

• • Conditions could include size limits, location close to the main house, and water collection requirements to reduce environmental impact.