A laneway home isn't a renovation; it's a second residence built from grade up on your property. New foundation, new framing, new envelope, new services. Done poorly, it's the most expensive shed in your neighborhood. Done well, it's a home for your relatives, a long-term rental, or a place you eventually downsize into yourself.
The work
A laneway home is, in every meaningful sense, a brand-new house. Excavation, footing pours, foundation walls, framing, sheathing, weather barrier, windows, roofing, mechanicals, finishes: the whole sequence, just at a smaller footprint. The build itself is straightforward for any contractor with house-building experience. The hard part is everything that happens before the shovel goes in: zoning confirmation, site servicing, tree retention, FSR calculations, design that fits the lot, and a permit package the municipality can actually approve.
We've been doing site-built construction in the Lower Mainland since 2014. A laneway is not a kit; it's a custom build at a small scale. We treat it that way.
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Why Coastal
The laneway market in Greater Vancouver has two kinds of builders: pre-fab resellers who drop a manufactured unit on a foundation someone else poured, and full-service general contractors who do the whole build on site. We're the second kind. Same names from your first site visit through final inspection. Same crew that's renovating residential and commercial builds across Vancouver.
We'll coordinate a pre-fab supplier if that's the right call for your project; some lots and budgets favour it. But we won't pretend a turnkey kit-home solves the hard parts. Permits, services, and site work still happen on the ground.
Book a feasibility visit →Provincial zoning, rewritten
Bill 44, BC's Small-Scale Multi-Unit Housing legislation, requires municipalities to allow additional units on lots once limited to a single house or duplex. That's the reason a detached laneway home or garden suite is now possible on many properties that didn't permit one before.
What's allowed varies city to city, and bylaws are rewritten occasionally. We confirm what your specific lot permits before we design or price anything.
Common project types
Most ADU projects fit one of three shapes. Each has its own permit path, site-work demands, and budget range, and the right answer depends as much on the lot as on the homeowner.
A one-storey detached dwelling at the rear of the lot, typically 500–800 sq ft. The most-built ADU type in Metro Vancouver and the easiest to permit on a standard single-family lot.
A taller, larger ADU, usually 800–1,200 sq ft across two levels. Common where FSR allows additional height and the lot can absorb a more substantial structure.
A ground-floor garage with a one- or two-bedroom unit above. Common in older Vancouver and South Surrey neighbourhoods where lane access supports it.
INTEGRITY ABOVE ALL
The biggest hidden cost on an ADU project is finding out after the deposit that your lot can't actually accommodate one. Our feasibility visit covers four things, in this order. If any of them are a hard "no," we tell you on day one.
Zoning designation, floor space ratio remaining after the existing home, setback rules from rear lane and side lots, and any overlay restrictions (heritage, view cones, agricultural). We confirm what your lot legally allows before any design work begins.
Water, sanitary, storm, and electrical service capacity. Some lots have a clean independent run to the lane; others require costly upgrades to the main service or a complex tie-in through the front. We check what's there and what's needed before quoting.
Most Metro Vancouver municipalities have strict tree-protection bylaws, and a mature tree in the rear yard can quietly veto a laneway footprint. We map every protected tree, drip line, and required setback as part of the feasibility report.
Some municipalities have a streamlined laneway program; others run every ADU through full development permit review. We map the actual review path for your address (and the realistic timeline) before you commit to a design or a budget.
We run feasibility as a fixed-fee engagement before any design contract, so if your lot doesn't work, you haven't paid for drawings you can't use.
Request a feasibility visit →How an ADU build runs
A laneway home is a full new build, not a minor renovation. Each phase has its own pace, and we keep you informed at every step.
Site visit, lot eligibility check, FSR calc, services audit, tree assessment, and a concept sketch that fits the lot. You decide whether to proceed before any design fees are committed.
Architectural drawings, structural and mechanical engineering, energy compliance, arborist report if required, and submission to the municipality. Review timelines vary wildly: Vancouver longer, smaller municipalities faster.
Tree protection, demolition where required, excavation, service trenching, foundation pour, and underground rough-ins. The most disruptive phase for the existing home; we sequence it carefully.
Framing, sheathing, roofing, envelope, windows, mechanical and electrical rough-in, insulation, drywall, and interior finishes. Coordinated trades through to final paint and millwork.
Final mechanical, electrical, plumbing, and building inspections. Occupancy permit issued. Keys, documentation, and warranty package handed over. Annual follow-up included.
We thought about a laneway for two years before we called Coastal. The thing that surprised us was the feasibility visit: they came out, told us what FSR we had left, walked the rear yard, and identified a tree we'd have to design around. We had a clear picture of cost and timeline before we paid for a single drawing. Sixteen months later, our daughter and her partner live in the back. It's the best decision we've made on the property.
Common questions
Don't see yours here? Just call us.
(778) 878-9610Let's talk laneway homes
Free, candid, no pitch. Tell us what you're picturing. A laneway rental, a suite for family, the place you'll eventually downsize into. We'll start with what your lot allows, then tell you honestly what it takes and whether we're the right fit.