Crawl Space Repair and Encapsulation in Greater Victoria

What crawl space repair covers, and which parts are ours

Crawl space repair is not one trade, it is a cluster of them. The single most useful thing to settle before you take quotes is which parts a given company performs and which it subcontracts or quietly leaves to you. Here is our side of that line, stated plainly.

We publish this because the alternative is worse for you. A quote that silently folds mould remediation, framing repair and pest work into a liner price is either padding the number or planning to skip those parts once the hatch closes. Ask every company you speak to to mark its own version of this table before you compare prices, because two quotes covering different rows are not comparable at all.

What an encapsulation actually includes

A loose sheet of plastic laid over the dirt is not an encapsulation. It is the most common thing already sitting under a house when a homeowner calls about a musty smell, and it is why so many people believe the approach does not work.

The US Department of Energy publishes the reference assembly in its Building America Solution Center: insulation on the walls rather than in the floor above, run down to grade and then a further 24 inches (610 mm), over a 6 mil polyethylene vapour retarder that covers the floor and turns up the perimeter walls, seams overlapped 6 inches at the code minimum and 12 inches recommended.

Three details separate that from a plastic sheet. The barrier is continuous, floor to wall. It is mechanically fastened and taped rather than laid loose. And the insulation moves from the floor above to the perimeter wall, which is what brings the crawl space inside the heated envelope of the house instead of leaving it an outdoor space with a lid on it.

Sealing the vents changes which rules apply

This is the part the national how-to articles leave out, and it is the part that decides whether a crawl space repair passes inspection in British Columbia. Section 9.18 of the BC Building Code treats crawl spaces as either heated or unheated, and the split does not depend on a furnace being down there. Encapsulating a vented crawl space moves it across that line on purpose, and the requirements for ground cover, walls and ventilation move with it.

The free-access edition of the Code that publishes this clause text is offline as this page is reviewed, so the citations below go to the Building Code Appeal Board instead. Those decisions quote the clauses verbatim, and unlike the Code itself they show how the argument actually got settled.

Those two decisions settle the two arguments a homeowner is most likely to have during a crawl space repair. You may use a poly liner, and a building official may not insist on concrete as a blanket policy. And a sealed crawl space is not merely sealed: it still has to be ventilated as part of the house, which is exactly why a proper encapsulation arrives with conditioned air or a dehumidifier rather than just closing the vents.

The practical consequence is the one worth pressing a contractor on. A quote that seals the vents but leaves the walls uninsulated and the space with no mechanical ventilation has not produced a heated crawl space. It has produced an unvented unheated one, which is the assembly that traps moisture instead of removing it.

What a repair crew has to do before it goes under the house

A crawl space meets the legal definition of a confined space in British Columbia, and that changes what a legitimate company does before anyone crawls in. Under Part 9 of the Occupational Health and Safety Regulation, a confined space is an area that is enclosed or partially enclosed, is not designed or intended for continuous human occupancy, has limited or restricted means for entry or exit that may complicate first aid or rescue, and is large enough and so configured that a worker could enter to perform assigned work. A typical Victoria crawl space satisfies all four tests.

What follows from that is not discretionary. The employer must hold a written confined space entry program, a hazard assessment of the space, and written safe work procedures covering entry permits, lockout, verification and testing, ventilation, standby persons and rescue. Under the same Part 9 rules, where a flammable or explosive atmosphere in excess of 20% of the lower explosive limit could develop, the atmosphere must be monitored continuously.

For a homeowner that reduces to one short question worth asking before anyone is hired: do you treat this as a confined space entry, and who is the standby person while your worker is under my floor. A company doing crawl space repair properly answers without pausing. The same answer explains a real part of why the published cost ranges further down sit where they do.

How to check a crawl space repair company in British Columbia

Two checks take about five minutes between them and are worth more than a page of reviews.

• Pull a clearance letter. WorkSafeBC runs a free search that reports whether a business is registered and paying its premiums. Its own guidance is blunt about the stakes: to be absolved of liability for a subcontractor’s unpaid premiums you need a letter confirming the firm was active and in good standing for the entire period of the contract.
• Know where you stand as the person hiring. WorkSafeBC guidance for homeowners draws the line at the independent business: hire one and you are its customer, but if it is not registered and paying, you could be held responsible for its premiums. Hire an individual who is not in business for a one-time job instead and the threshold is 24 or more total hours, past which you are required to register with WorkSafeBC yourself.
• Ask for the humidity target in writing, and for the method of hitting it. A repair sold without a number cannot be checked after the hatch closes.
• Ask which rows of the scope table above the price actually covers, and which it does not.

How thick the liner should be

The Code number is a floor, not a specification. The ground cover minimum quoted in BCAB #1373 is 0.10 mm polyethylene, roughly 4 mil. Liners sold for encapsulation work are commonly 10 mil to 20 mil, because sheet at the code minimum tears the first time anyone crawls across it, and a crawl space repair gets judged years later rather than on handover day.

That choice is not free, and it is not large either. This Old House prices liner by gauge: about $0.05 to $0.20 per square foot at 4 mil, and $0.40 to $0.60 per square foot at 20 mil. Materials run 30% to 50% of an encapsulation total. Across a 1,000 square foot crawl space, the step from code minimum to the heaviest liner is a few hundred dollars of material inside a five-figure job, which is why specifying it is worth more than haggling over it.

Humidity is the number that tells you it worked

A sealed crawl space is judged on what the air inside it does after the liner goes down, and there is a published target. The US EPA advises keeping indoor humidity below 60 percent and ideally between 30 and 50 percent relative humidity, and notes that materials dried within 24 to 48 hours of a leak will in most cases not grow mould.

That is why an encapsulation in this climate normally includes a dehumidifier or a supply of conditioned air, and not the liner alone. A sealed space with no moisture removal has nowhere to send the water vapour already held in the soil and the framing. A cheap hygrometer left on a joist for a week is the honest test of whether the work did what it was sold to do.

What published data says the work costs

We do not publish a price for our own work, because the number moves with square footage, headroom, standing water, and what is already growing under the floor. What can be published is what independent guides report the market charging, so a quote can be sanity checked before anyone visits.

Neither column is a Greater Victoria number and neither is a quote from us. Read them as the shape of the market: a liner-only job in the low five figures at most, and a drained, insulated, dehumidified space costing roughly twice a bare encapsulation.

The line items left off a cheap quote are the ones that decide whether the space stays dry. On top of the liner work, the same Ontario 2026 guide lists mould remediation at $500 to $4,000 and up, drainage with a sump pump at $1,000 to $3,000, and a crawl space rated dehumidifier at $1,200 to $2,500. A quote materially cheaper than its neighbours has usually dropped one of those three, and the scope table near the top of this page is how you find out which.

What to have ready before an inspection

The assessment goes faster, and the quote comes back tighter, when these are known before anyone opens the hatch.

• Roughly how many square feet the crawl space covers, and the headroom at its lowest point.
• Whether water pools down there after a storm, and where it comes in. Standing water is a drainage problem before it is a liner problem, which usually points at perimeter drains.
• What the ground is now: bare soil, an old sheet of poly, a concrete skim coat.
• Whether the space is vented to the outside, and whether any ducts or heating equipment run through it. That is the heated or unheated question above.
• Any cracking in the foundation wall around the crawl space, which is a separate scope from the liner. See crack repair and, where a full basement is also involved, basement waterproofing and our guide to basement waterproofing cost in Victoria.
• Whether anything in the crawl space has already been disturbed, rebuilt or partly lined by someone else, and roughly when.