Geotechnical Reports for a New Home in Vancouver and Burnaby
Everything you see in a finished home sits on something you never see: the soil. Before a new house, duplex or laneway home goes up, someone has to confirm that the ground can carry it, that the excavation will stay stable, and that water will be managed. That is the job of a geotechnical engineer, and the document they produce is usually called a geotechnical report.
This guide explains what a geotechnical report covers, when Vancouver and Burnaby expect one, what the engineer does during construction, and how to plan for it so it doesn’t become a surprise.
What a geotechnical report actually is
A geotechnical report is a professional engineer’s assessment of the ground under and around your future home, with recommendations for how to build on it. In BC, Engineers and Geoscientists BC publishes guidelines for this work, and they apply to houses (Part 9 of the BC Building Code) as well as larger buildings.
A typical report for a new home covers:
- Site investigation: a review of existing information, then test holes drilled or dug to see the soil layers, plus logs describing what was found.
- Groundwater: how high the water table is and how it might behave in wet months. The guidelines say groundwater should be monitored unless it can be shown to be unnecessary.
- Foundation recommendations: how much load the soil can safely carry, how deep footings should go, and whether anything special (engineered fill, piles, a raft slab) is needed.
- Excavation and slopes: safe cut angles, whether shoring is needed, and how to protect neighbouring properties.
- Drainage and below-grade walls: earth and water pressures on basement walls, perimeter drainage and slab support.
- Seismic considerations and expected settlement or movement.
When Burnaby requires geotechnical work
Burnaby’s submission checklist for new single-family and duplex dwellings in the R1 zone (revised July 2026) lists two separate geotechnical items:
| Item | When it’s required | Who signs it |
|---|---|---|
| Letter of Assurance, Schedule B: Geotechnical | Listed as a standard document at building permit application | A professional engineer (P.Eng.) with a permit to practice |
| Geotechnical report | Only if the property is flagged as a floodplain or slope instability area | A professional engineer |
The Letter of Assurance is the engineer’s formal commitment to design the geotechnical aspects of the project and to review the work on site. So even on a lot that isn’t flagged, you should expect a geotechnical engineer to be part of your Burnaby design team. Burnaby’s checklists change from time to time, so confirm the current version with the City before you apply.
When Vancouver requires geotechnical work
The City of Vancouver’s bulletin on geotechnical and shoring design for one- and two-family homes (2016-005-BU, revised 2017) says additional design and submittals are required in three situations:
- Peat or liquefiable soils
- Deep basements, defined as more than 8 feet deep
- Sites next to a previous excavation where the amount of undisturbed native soil is limited or unknown
In those cases the City expects a detailed geotechnical report, a shoring design, fill specifications and, for peat areas, a sealed impact statement. The engineer must also supervise the excavation and shoring, survey neighbouring properties before work starts, notify neighbours and manage groundwater. The City can also ask for an independent review of the report where conditions are unusually complex.
Outside those situations, geotechnical input still shows up during inspections. Vancouver’s low-density housing inspection guide asks for a geotechnical engineer’s letter confirming soil bearing capacity and suitable subsurface conditions at the footings and forms stage “where applicable”, and calls for a geotechnical engineer to direct repairs where soil under sumps or sewer lines is unstable.
Soil problems that are common in the Lower Mainland
BC’s Homeowner Protection Office (a branch of BC Housing) published a best-practices guide for builders on foundations and geotechnical challenges. The conditions it flags are the ones that most often change a design here:
- Peat and organic soils, which keep settling as they decompose and are generally unsuitable to build on directly.
- Old or unmanaged fill, which can be loose, mixed or sitting on buried organic material.
- Soft clays, which compress under load and can settle unevenly.
- High groundwater, which affects basement drainage and waterproofing.
- Slopes, especially where fill is placed at the top or soil is removed at the bottom.
The guide recommends involving a geotechnical engineer when a site or the slope below it is steeper than about 20 degrees (about 10 degrees in clay), when it is below the flood construction level, or when organic, compressible or expansive soils are present. It also notes that a geotechnical engineer can reduce the risk of problems even when one isn’t required.
What the geotechnical engineer does during construction
The report is only half the job. Once the Letter of Assurance is signed, the engineer reviews the work on site to confirm that the ground matches what the design assumed. Typical visits include:
- Excavation: checking that cuts are stable and, where needed, shoring is built as designed.
- Footing subgrade: confirming the soil at the bottom of the excavation is suitable before forms and concrete go in.
- Fill and under-slab: checking that any fill is the right material and properly compacted.
- Drainage: reviewing perimeter drainage and any groundwater measures.
- Completion: issuing the final letter (Schedule C-B) that the City needs before occupancy.
If the soil turns out different from what the test holes showed, the engineer adjusts the recommendations on the spot. That is far cheaper than discovering a problem after the concrete is poured.
How it affects your budget and schedule
The cost of geotechnical work depends on the lot, the depth of the basement and how much investigation is needed, so get a written quote from the engineer once your design is taking shape. A simple, flat lot with good soil usually needs a modest investigation and a few site visits. A sloped lot, a deep basement or a site with peat or high groundwater needs more testing, shoring design and supervision, and may lead to a different foundation.
On schedule, the main thing is order: the geotechnical investigation belongs in the design stage, before the permit application, not after. On a straightforward lot (relatively flat, no significant trees, little slope), building a custom home takes about 10 months from foundation to finish once permits are in hand. Poor soil, groundwater or shoring can add to that, which is exactly why it pays to know early.
Questions to ask before you hire a geotechnical engineer
- Are you registered with Engineers and Geoscientists BC, and does your firm hold a permit to practice?
- Will you sign the Schedule B Letter of Assurance and carry out the field reviews through to the final letter?
- How many test holes do you plan, and will you monitor groundwater?
- Does your quote include site visits during excavation and footings, or are those billed separately?
- Do you carry professional liability insurance suitable for this work?
Related reading
- Building inspections for a new home in Vancouver and Burnaby
- How long does it take to build a custom home?
- How to compare builder quotes in BC
- Building permits & approvals support
Wondering what the soil on your lot could mean for your foundation and basement?
Sources
- City of Burnaby: submission checklist, R1 new single-family and duplex dwellings (PDF)
- City of Vancouver: Bulletin 2016-005-BU, geotechnical and shoring design for 1-2 family homes (PDF)
- City of Vancouver: low-density housing inspection stages guide (PDF)
- Engineers and Geoscientists BC: Geotechnical Engineering Services for Building Projects (v2.1, 2021)
- Homeowner Protection Office: Housing Foundations and Geotechnical Challenges, best practices for residential builders in BC (PDF)
Requirements and timelines are approximate and change over time. Confirm what applies to your lot with your municipality and a registered geotechnical engineer.
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