Information for Building a Triplex or Fourplex


Please note: In late 2023 and spring 2024, the Province introduced housing-related legislative changes that require the City to rewrite municipal rules around zoning, development, fees and charges, and public engagement. Visit Housing Changes in Coquitlam for more information.


The Zoning Bylaw permits a range of small-scale, ground-oriented housing options in lower-density neighbourhoods throughout the city. This includes a range of options including single-detached houses, backyard suites, duplexes, triplexes, fourplexes and multiplexes. 

These pages are for property owners who are interested in building either a triplex or a fourplex in areas where small-scale housing is allowed, including the R-1, R-2, R-3 and R-4 zones. See the following web pages to check whether your property qualifies.

This information is intended to be a resource to get you started, to direct you to where to find more information, and to highlight some things to think about as you plan to build a triplex or fourplex on your property:

Make Sure Your Property Qualifies

Below are questions to determine if your property is in a low-density residential area (which allows triplexes and fourplexes) and if your property meets the minimum size criteria.

To take advantage of small-scale housing you need to answer YES to ALL the following questions:

  1. Is my property in a low-density residential area, where triplexes and fourplexes are allowed? 
  2. Is my property in a Small-Scale Residential zone, which will allow a triplex or a fourplex? These zones include the R-1, R-2, R-3 and R-4 zones. 
  3. Does my property meet the minimum lot width and minimum lot area required for a triplex or fourplex? Explore your property’s lot size on QtheMap. If you want to build on an existing lot, the minimum lot size is 280 m2 (around 3,014 ft2) and there is no minimum width. If you want to subdivide a lot for small-scale housing, check the lot size requirements in the Zoning Bylaw. 

Before you start, if you answer YES to any of the following questions, please contact Development Services staff for more information: 

  1. Was the existing house on my property built before 1945? 
  2. Is there a creek on, or next to, my property?
  3. Is there a steep slope on, or next to, my property?
  4. Is my property located in a Transit-Oriented Area or another planning study area?

Development Application Process and Standard Plans

To simplify the Development Permit process, the City of Coquitlam developed Standard Plans for triplexes and fourplexes for the public to use and modify to fit their property’s size and slope. Using a standard plan package, which is an approved design, your hired professionals can put together a triplex or fourplex Development Permit application package quicker. This will also result in a faster and more predictable staff review. See the Standard Plans Development Application Process handout (PDF) for more details. 

If your property is not rectangular, is on a corner, does not have current or future lane access per Schedule R (PDF) of the Zoning Bylaw, or you wish to use your own design, please see our RT-1 Development Application Process handout (PDF)

Triplex or Fourplex Standard Plans

Explore our catalogue of Standard Plan Packages that vary in style and find one that meets your needs and property.

  1. 1 Computed generated image of a fourplex housing project.
  2. 2 Computed generated image of a fourplex housing project.
  3. 3 Computed generated image of a fourplex housing project.
  4. 4 Computed generated image of a fourplex housing project.
  5. 5 Computed generated image of a triplex housing project.
  6. 6 Computed generated image of a triplex housing project.

The Standard Plans need to be adjusted by your designer or architect to fit your property (e.g. slope, garbage pick-up location, existing trees, utility servicing requirements, etc.). The standard plans have been created with Coquitlam’s sloping properties in mind; with the individual units able to be adjusted independently from the other units, to build as close as possible to match the existing grade of your property. Your designer or architect may also want to consider EV charging capability and BC Energy Step Code Level 3 eligibility.

Your designer or architect will need to adjust the plan package for your property, including:

  • Limiting outside stairs and retaining walls proposed - to improve the project’s fit into the neighbourhood;
  • Limiting the number of stairs between the garbage enclosure and the garbage pick-up location;
  • Incorporating retained trees in the site design;
  • Anticipating storm water management and utility locations, including the possibility of BC Hydro infrastructure.

As the intent of the Standard Plans is to simplify the Development Permit process, the interior layout must remain substantially the same and the exterior appearance and materials (including window and door sizes and specifications, fence details, landscaping details) are not permitted to be changed if you wish to participate in the simplified Standard Plan process. If the interior layout is substantially altered or the exterior appearance of the building is changed, the application must follow the normal Development Permit design review process which may add to the review time and require further revision cycles.

If you are interested in using one of the Standard Plans packages, contact the Development Information Team with the option you want to use and a copy of a current (within one year) topographic survey. The Development Information Team can be reached by emailing, calling 604-927-3430, or in-person at City Hall. Staff will reply with the estimated elevations to be followed along the road frontage(s), a copy of the appropriate CAD drawings, and further instructions. 

The Application Process 

Before you can apply for a Building Permit to build your proposed triplex or fourplex you need to receive a number of approvals from the City. 

You may also need:

  • A Subdivision for any required road of lane dedications. 
  • A Watercourse Protection Development Permit if the proposed development is located within a Watercourse Protection Development Permit Area in the Maillardville, Austin Heights and Burquitlam-Lougheed Neighbourhood Plans). More information is available in our Watercourse Protection Development Permit Guide (PDF).

More information is available on our Builder Resources page or in our Development Permit Application Guide (PDF), which outlines the process for obtaining a Development Permit.

For more information on using the City’s standard plans, read our Standard Plan Development Application Process handout (PDF). If you are using a custom design, please read our RT-1 Development Application Process handout (PDF)

Hire Professionals to Help

You will need to hire professionals to help you as part of your project team to work with you on different pieces of your application. We have included links to websites of professional organizations, where possible. This is a high level list of some of the professionals you may require, and examples of work they can provide.

BC Land Surveyor

  • Produces a certified Topographic Plan with: elevation points, location and sizes of trees on or next to your property; any easements or statutory right-of-ways registered on the property; any watercourse or slope and the required setbacks from these natural features.
  • Produces a Subdivision Plan which is required for a Subdivision Application
  • Produces a Strata Plan to create separate legal titles for strata units.

Building Designer or Architect

  • Designs and produces plans of the building, or if using the City’s standard plans, they adjust them to fit your property’s slope, garbage pick-up location, existing trees, and any utility servicing requirements. An architect is not required to design a triplex or fourplex. However, an engineer or architect will be required to be the Coordinating Registered Professional at the time of the Building Permit application.

Civil Engineer

  • Designs and produces plans of the water, sanitary sewer, and storm sewer connections to your triplex or fourplex.
  • Designs plans, oversees construction, and signs-off on Frontage Works.
  • May be the Coordinating Registered Professional at the time of the Building Permit application.

Qualified Environmental Professional (QEP)

  • A Qualified Environmental Professional is defined in Part 5 (PDF), Section 523 of the Zoning Bylaw (Riparian Areas Regulation).
  • Produces a Riparian Areas Protection Regulation detailed assessment report if a development is proposed within the Streamside Protection and Enhancement Area (SPEA) as shown on QtheMap.

Qualified Tree Expert (QTE)

Geotechnical Engineer   

  • Evaluates and reports on the soil conditions for construction and slope stability, making recommendations as to construction methods, setbacks from slopes, and monitoring to allow for construction on your property.

Heritage Professional

  • Evaluates and reports on the conservation of buildings, and other historically significant features, and the significance of a property in relation to Coquitlam’s cultural heritage.
  • Works with the applicant and other development professionals to ensure character defining elements are conserved and celebrated within a Heritage Revitalization Agreement development.
  • To find out if your property is on the City’s Heritage Inventory, contact the Development Information Team by email.

Landscape Designer or Landscape Architect

  • Both of these professionals can design and produce plans for your property’s landscaping. Hiring a Landscape Designer is acceptable when there are no street trees required to be planted. A Landscape Architect is the required professional for designing the plans, and overseeing the installation of any required street tree planting. If your development is required to install street trees, it may make economic sense to have your Landscape Architect design your property’s landscaping as well being responsible for the boulevard landscaping. 

Coordinating Registered Professional (CRP)

  • Triplex and fourplex development applications are considered “complex” as defined in the City’s Building Bylaw. For many Building Permit applications for triplexes or fourplexes, a project will require, at a minimum, a Civil Engineer, and a Structural Engineer to provide their professional services for a proposed project. Where two or more Registered Professionals are providing their services on a project, they need the oversight of a Coordinating Registered Professional (CRP).
  • A CRP (may be an architect or an engineer) is required at the time of Building Permit application for a triplex or fourplex to coordinate all professionals working on the development and to sign-off on the required BC Building Code Schedules stating that the work has been completed to conform to the approved Development Permit.

Applicable Fees and Charges

It is important that you talk to professionals about creating a budget for your Housing Choices project. There may be other costs associated with your development that are not outlined here, and you will need to ensure you have created an appropriate project budget.

Aside from the hiring of professionals required to complete your application(s), and the construction crews required to work on the development, here are some (but not all) of the items that have financial implications. These fees, charges, and securities are required at different times during your development process and City staff will be able to let you know when these would be payable, and which would be applicable to your project.

Application Fees (See the Fees and Charges page) are associated with:

Engineering Works

All new developments contribute to upgrading adjacent streetscapes to a modern urban standard, including curbs, gutters, sidewalks, lighting, landscaping and rear lane improvements. These upgraded street works are called “Frontage Works”. You will be required to either pay into the Frontage Works Program (staff will confirm if you’re eligible through the application process) or construct the Frontage Works as part of your project. Your Civil Engineer can provide you with a cost estimate for these works. The Engineering & Public Works Fees and Charges listing in Schedule F of the Fees and Charges Bylaw (PDF) can be helpful to estimate the costs. Costs may be associated with the following:

  • “Capping”, or sealing off, old services (storm sewer, water, sanitary sewer, electrical, gas);
  • Upgrading services to newer or larger sized equipment; 
  • Extending new services to your property; and
  • Inspection Fees.

Refundable Securities

Refundable securities will need to be provided to the City to complete specific works. Some of these securities may include: 

  • A Development Permit security, at 2.5% of the estimated cost of construction;
  • A Frontage Works security for works and services (if you are participating in the Frontage Works Program), at 110% of the estimate provided by your Engineering consultant; and
  • An Engineering & Public Works security for damage deposits. 

These deposits are refunded once City staff are satisfied that the work has been completed and maintained after a set period of time.

City Amenity Cost Charges (ACCs)

Before a Building Permit is issued, City Amenity Cost Charge (ACC) payments are due. ACCs help pay for amenities including community centres, recreation facilities and libraries, which are needed to serve the community due to growth.

City Development Cost Charges (DCCs)

Before a Building Permit is issued, City Development Cost Charge (DCC) payments are due. DCCs help pay for transportation, water, sewer, drainage, park acquisition and some park development projects which are needed to serve the community due to growth. 

Other Agencies’ Development Cost Charges

In addition to the City’s DCCs, other agencies have development charges that we collect on their behalf at the time of issuing a Building Permit. These charges are subject to change and may increase during the time you are in application with the City. Check with Development Planning to confirm the rates which would be in effect. 

Links to information on these various charges are listed below can be found at the City’s Fees and Charges page:

  • Greater Vancouver Sewerage and Drainage District Development Cost Charge (Coquitlam is in the Fraser Sewerage Area); 
  • Greater Vancouver Water District Development Cost Charge;
  • Translink Development Cost Charges; and
  • School Site Acquisition Charges.

Additional Resources

In addition to the designing your project to meet the Design Guidelines (PDF) as part of your Development Permit Application package, your project must meet all other City Bylaw requirements, including the requirements set out in the Zoning Bylaw

Some helpful Zoning Bylaw links include:

Other considerations:

  • Floor Area or Floor Area Ratio is a calculation used to determine how much of a property can be developed. It includes the area of all garages, all levels of stairs, and basements. Crawl spaces (spaces 1.2m, or 4ft., or less in height) are not included. Carports and decks are excluded from the Floor Area calculation, but still count towards the maximum allowable Lot Coverage. The maximum permitted Floor Area is calculated using the area of the lot prior to any road or lane dedications multiplied by the permitted density ratio in the Zoning Bylaw.
  • Lot Coverage is calculated using the area of the lot after any lane or road dedications have been applied.
  • Lot grading plans are required indicating the existing and finished grades and all top of wall and bottom of wall elevations for any proposed retaining walls.
  • Accessory dwelling units are allowed so long as the total number of dwelling units (principal and accessory) on your property is four or less (in the R-1, R-2 and R-3 zones). The City will not accept a design which could possibly be converted to more than four units in the future.   
  • Each housing unit must have a minimum 20 m2 (215 sq. ft.) of outdoor space. Dwelling units may be designed to share outdoor space.

Designing with the Slope of the Property

The building and site improvements proposed for your property should not impact your neighbour’s property. We would prefer your project be designed with no retaining walls, however, minimum stepped retaining is allowed (see the Zoning Bylaw, Maximum Retaining Wall Height Section 516 (PDF)).

All submitted plans should show the existing and proposed elevations, at all changes in grade, and the existing elevations at least 1 metre beyond the property lines of the site proposed to be developed.

Garbage and Recycling Enclosure

Garbage and green waste carts and must be stored in a garage or in a structure that is fully enclosed (with a roof) in order to be wildlife resistant. Enclosures must be designed so that there are no gaps which may give entry to wildlife (for example, no lattice). Each triplex or fourplex unit will be provided one 240L size cart for organic waste, one 240L size cart for garbage, a blue recycling box, and a glass recycling box. See the Waste Collection Brochure (PDF) for information on the number, size and enclosure requirements for solid waste carts.

BC Hydro Requirements

You should discuss your hydro requirements with BC Hydro. If there is a requirement from BC Hydro to install a Local Pad Transformer (LPT), the City prefers it to be located away from the front of the building and screened with appropriate landscaping. An electrical room may also be required in the building design.

Be A Good Neighbour During Development

On September 3, 2019, Council endorsed the Good Neighbour Development Policy. Please review this policy and ensure that you understand what this means for you as a developer. Note that, at this time, no declaration is needed as part of this application. However, a declaration will be needed before the City will issue a Building Permit or Demolition Permit.