Duplex and Multiplex Costs
Single custom homes, homes with secondary suites, and vacation homes.
See also: Laneway House Costs, Single Home Costs
Estimated costs based on similar recent projects.
Actual costs will vary depending on the site and design. Updated March 2026.
Hard Costs vs Soft Costs
Every construction project has both “hard costs” for the actual built components, and “soft costs” which are usually the design, consultant, and city permit fees. When added together these become the “Total Project Cost”.
As a high level rule of thumb, we recommend estimating lane houses at $600psf Project Cost,
and Houses/Plexes at $500psf.
The difference is because smaller homes always cost more psf vs big homes (becuase they have all the expensive parts of the house, but none of the cheaper rooms that dilute the cost of a larger home).
Project Cost = Soft Costs + Hard Costs
Soft Costs
Site Survey / Arborist
Designer / Architect
Engineers and Consultants
City Permit Fees and Development Fees
3rd Party Fees (Legal, Electricity Service, Insurance)
Taxes (GST in BC)
Hard Costs
Demolition / Deconstruction
Asbestos / Lead Abatement
Tree Removal / Protection
Site Servicing (Sewer, Power, Water)
The Building!
Landscape (Soil, Plants, Pathways, Fences, Retaining)
Taxes (PST and GST in BC)
What’s Not Included in our estimate for Project Cost?
The interest / fees for the Construction loan are not included. Owners / Developers finance their projects through a range of sources, ranging from cash, to HELOC lines of credit, to Construction Loans or Private Financing.
Some institutions, like Vancity, provide special financing packages for multiplex homes.
The cost of this financing is separate from our work as a design and build team.
Marketing or other development and sales related costs
Plex Costs
Duplexes and multiplexes are now allowed in many cities. These are quite different from houses with suites because they can be stratified and sold as separate units (or) they can be retained under one ownership and rented.
Plex prices can vary a lot by site, and by design, but the typical Project Cost for a Lanefab net zero plex in Vancouver is ~$500 psf.
If not building to the net-zero or passive house standard, then it is roughly $20psf less.
This is a Total Project Cost (not including land or finance or Hydro costs)
For a typical 4000sf to 8000sf plex it looks like this:
~$30 psf for Design and Consultants
~$40 psf for City Permit Fees
~$410 psf for Hard Costs (Hazmat, Demo, Landscape, Building and GST)
~$20 psf upgrade to Net-Zero / Passive House
So, this is ~$500 psf - n/i land, finance costs or the BC Hydro Service (as it is a large variable).
Lanefab’s efficient buildings and smart power systems can usually reduce the size of the Hydro service but they might be:
~$2,000 for a 200A service serving 1 to 3 units
~$40,000 for 400A service serving 4 to 6 units
~$120k for a Pad Mounted Transformer serving 6 or more units
(or where there are a lot of car charging parking spaces included)
Timing of Costs
For a typical custom lane house, we would work with you for around 1 to 1.5 years to do the design and permitting, 2 months for hazmat and demo, and ~1 year for the construction. The permitting time varies a lot depending on which city you are building in. Vancouver can be 6 months to a year for permits, while Kelowna or Burnaby could be much faster.
So, in the first year the Soft Costs (design, consultants, city feees) would need to be paid.
In the second / third year, after the permit is issued, and the construction contract is signed, then the Hard Costs would be payable in instalments over the course of the build.
Here’s more info on the Design Process and Construction Process
Net Zero / Passive House Density Bonus - Upgrade Cost
In the city of Vancouver there is a ~20% density bonus for zero emissions buildings that certify as a CHBA Net Zero home or PHI Passive House.
These homes are highly efficient, all electric, and sometimes have either thicker walls or solar panels. There is usually some extra design and engineering work involved, as well as certification costs.
For a 4000sf laneway house the density bonus is an extra 800sf and the upgrade cost is roughly $80k to $100k.
Vancouver Net Zero Plex on a 33x122 Lot:
Base 4000sf plex ‘Total Project Cost’ = $2m
Net Zero Upgrade = $100k
Additional 800sf of floor area at ~$500psf = $400k
Total Project Cost for a 4800sf Net Zero Plex = $2.5m
Vancouver Net Zero Plex on a 50x122 Lot:
Base 6000sf plex ‘Total Project Cost’ = $3m
Net Zero Upgrade = $120k
Additional 1000sf of floor area at $500psf = $500k
Total Project Cost for a 3360sf Net Zero Home = $3.62m
Here’s more info on the Design Process and Construction Process
What’s Included? How is a Lanefab Home Different?
Every single Lanefab home is built to a higher level of design, quality, comfort and performance compared to many of the ‘builder spec’ homes on the market.
Building Envelope:
Lanefab builds to a level of energy efficiency and comfort equivalent to Step 4 of the BC Energy Step code at a minimum. Many of our projects go above and beyond, but this is our baseline of quality and performance.
This includes 13” thick walls, triple glazed windows, fresh air exchanger, and an air source heat pump for heat and A/C.
Features and Finishes:
Our homes are all custom designed and include features like floor heat, extensive custom millwork, natural materials, unique finishes and careful design by our award winning team.
Upgrades and Air Quality:
Lanefab is one of the few builders offering a HEPA filter upgrade to the central HRV ventilation system. This can provide your family with smoke free air during the months when fire smoke can be a real danger.
We can also design and build a range of custom options, from rainwater tanks, to steam showers, to built in media systems, smart window shades, or custom edible gardens. Just ask!
Here’s more info on the Design Process and Construction Process
