London Ontario ARU Bedroom Mattress Guide: CP-1600-300 GFA Rules Explained

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London Ontario ARUs and CP-1600-300: A Plain-Language Summary

The City of London's Interim Control By-law CP-1600-300 governs how property owners can add Additional Residential Units (ARUs) to their homes. ARUs include basement apartments, garage lofts, additions, and internal secondary suites. The bylaw was introduced as London worked through its long-term ARU policy framework, and its core size restriction has practical consequences that most tenants and buyers don't fully think through until they're standing in the space.

The restriction: an ARU cannot exceed 80% of the gross floor area (GFA) of the primary dwelling. A 1,000 sq ft house can legally host an ARU of up to 800 sq ft. But many London homes are older bungalows in the 900-1,100 sq ft range, which means ARU bedrooms in these homes are compact by necessity.

The minimum floor area for an ARU in London is 25 square metres, or about 269 square feet. That's a very small apartment. A single bedroom within that unit could be 75-90 square feet at best, depending on how the kitchen, bathroom, and living area divide the remaining space.

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What the GFA Limit Means for Bedroom Size

Here's a worked example that captures what London ARU bedrooms actually look like in practice.

A typical older London bungalow might be 1,100 sq ft on the main floor. Under CP-1600-300, the basement ARU can be up to 880 sq ft (80% of 1,100). A functional one-bedroom basement apartment at 880 sq ft is genuinely liveable. The bedroom might be 130-150 sq ft, and a queen fits well.

But many basement ARUs in London are more constrained. A 900 sq ft bungalow gives a maximum 720 sq ft ARU. Carve out a kitchen (80 sq ft), bathroom (50 sq ft), and living area (180 sq ft), and the bedroom is around 100-120 sq ft. That's workable for a queen if the room is roughly rectangular, but borderline in an L-shape or irregular layout. A double at 54 x 75 inches gives about the same sleeping surface with more clearance.

One factor that often surprises ARU occupants: doorway width. Ontario Building Code requires a minimum 810 mm (about 32 inch) clear opening for bedroom doors. Standard mattress delivery involves getting the mattress around basement stairwells, which can be tight. Our white glove delivery team has navigated London basement stairwells before. When you call, tell us about the stairwell geometry so we can plan accordingly.

Choosing the Right Mattress for a Small ARU Bedroom

Small rooms benefit from a few mattress choices that don't apply in typical bedrooms.

Edge support matters more in a small room because you're likely to sit on the edge to put on shoes or dress. A mattress with a firm perimeter coil structure, like the Restonic ComfortCare line, holds its shape at the edge rather than collapsing. This makes the room more functional as a living space, not just a sleeping space.

Profile height also matters. Low-profile mattresses (8-10 inches) look less bulky in a small room and are easier to handle in tight stairwells. Our ComfortCare line runs at a practical mid-profile height that balances room aesthetics with sufficient coil depth. Very thick "pillow top" mattresses in a compact room can feel overwhelming and create a harder delivery situation.

Ontario Building Code Bedroom Standards That Apply

Beyond CP-1600-300's ARU size cap, the Ontario Building Code (OBC) sets minimum bedroom dimensions that apply to all residential construction including ARUs. These standards are worth knowing whether you're the tenant, landlord, or purchaser of an ARU unit.

Under the OBC, a bedroom used by one person must have a minimum floor area of 7 square metres (about 75 sq ft). A bedroom for two or more persons must be at least 11 square metres (about 118 sq ft). These are absolutes, not recommendations. A bedroom below these thresholds isn't legally a bedroom, which affects how the unit can be advertised and rented.

A 7 sq m (75 sq ft) room can technically hold a twin mattress and not much else. The minimum keeps the room legal; it doesn't make it comfortable. A room at 10-12 sq m (108-130 sq ft) gives a double or queen reasonable placement options and starts to feel liveable rather than merely legal.

If you're moving into an ARU and the landlord describes a room as a "double bedroom," it should meet or exceed the 11 sq m standard. If it's described as a "single bedroom," 7 sq m is the minimum. Ask before signing the lease, and bring a tape measure. We've heard from enough tenants who arrived to find a very different room than expected.

Mattress Delivery to London Ontario ARUs

We deliver white glove from our Brantford showroom to London and the greater London area. The white glove service includes bringing the mattress into the room, setting it up on the frame, and removing all packaging. Old mattress removal is available if you need the existing one gone.

For ARU basement deliveries specifically: tell us about the stairwell when you book. Our delivery team is comfortable with tight spiral staircases, narrow basement stair landings, and low-ceiling basement approaches. We'd rather know the constraints in advance than be surprised on delivery day.

Call Brad at (519) 770-0001 to confirm your London delivery address, discuss the room dimensions, and lock in a delivery slot. We work Monday through Friday during showroom hours and can often accommodate weekend deliveries with advance notice.

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