Concrete Coring in Vancouver: The Complete Guide
October 12, 2026
Concrete doesn’t glue itself to concrete. When a new slab, wall, or foundation needs to connect to an existing structure — a building addition, a slab extension, a new wall tied to an old foundation — the connection has to be engineered, not hoped for. That’s what rebar doweling (rebar planting) does: steel bars are drilled and epoxy-set into the existing concrete, and when the new concrete is poured around the exposed ends, old and new become one continuous structure.
At scanXpert, we perform rebar doweling across Greater Vancouver and BC — and every doweling job starts the same way our coring and cutting jobs do: with a GPR scan. See our rebar planting & doweling service page for the full service details.
What Is Rebar Doweling?
Rebar doweling — also called rebar planting — is the process of installing steel reinforcement bars into existing concrete to connect it to a new concrete pour. Holes are drilled into the old concrete to a specified diameter and depth, cleaned thoroughly, filled with high-strength structural epoxy, and fitted with rebar or dowel bars. Once the epoxy cures, formwork goes up and the new concrete is poured, locking onto the doweled steel. The result: the new section can’t separate, shift, or settle independently of the old.
How Doweling Is Done, Step by Step
- Layout and scanning. Dowel positions are marked per the design. Then the concrete is scanned with ground-penetrating radar to map existing rebar, conduits, and post-tension cables — new holes must never clash with what’s already embedded.
- Drilling. Holes are drilled with rotary-hammer or diamond core equipment to the specified diameter and embedment depth.
- Cleaning. Every hole is brushed and blown clean. Epoxy bond strength lives or dies on this step — dust is the enemy.
- Epoxy injection. Structural epoxy is injected from the back of the hole outward so no air is trapped.
- Bar insertion. Rebar is inserted with a slow twisting motion to full depth; alignment is checked.
- Cure, then pour. The epoxy cures on the manufacturer’s schedule. Then the new concrete is poured and tied to the doweled steel.
Where Doweling Gets Used
- Building additions and extensions tied to existing foundations
- New walls, columns, and slabs connected to old concrete
- Slab extensions and thickenings
- Seismic and structural upgrades
- Equipment pads and machinery foundations
- Stairs, landings, and retaining walls tied into existing structures
Why We Scan Before We Drill
A dowel hole drilled blind can sever existing rebar, cut an electrical conduit, or strike a post-tension cable — turning a connection detail into structural damage. GPR concrete scanning maps everything inside the concrete first: rebar location and depth, conduits, post-tension tendons, voids. On doweling jobs the scan does double duty — it keeps drilling safe and confirms the existing concrete is sound enough to anchor to.
What Weakens a Dowel
- Dirty holes. Dust left in the hole is the number-one cause of epoxy bond failure — brush and blow every hole.
- Wrong hole size. Too tight and the epoxy can’t surround the bar; too loose and bond area is wasted — diameter follows the epoxy spec.
- Rushing the cure. Loading or pouring before full cure compromises strength — cure times vary with temperature.
- Drilling blind. Hitting existing steel doesn’t just damage the structure; it can deflect the drill and ruin hole alignment.
Rebar Doweling Service in Vancouver, BC
If you need new concrete tied to existing structures, see our rebar planting & doweling service. We serve Greater Vancouver and all of BC, 24/7 — call (236) 868-2111 for a free quote, or request a quote online.
Frequently Asked Questions
How is doweling different from just pouring concrete against old concrete?
Concrete doesn’t bond structurally to concrete on its own — a cold joint between old and new pours can separate, leak, or shift. Dowels provide the steel continuity that makes the two pours act as one structure.
How strong is an epoxy-set dowel?
Installed correctly — correct diameter, cleaned holes, structural epoxy, full cure — epoxy-anchored dowels develop strength comparable to cast-in-place rebar. Installation discipline is everything.
How deep do dowel holes go?
Depth depends on bar diameter, the epoxy manufacturer’s data, and the engineer’s design — typically a multiple of the bar diameter. We drill to the specified embedment and verify it.
Can you dowel into decades-old concrete?
Yes, as long as the existing concrete is sound — age alone isn’t a barrier. We GPR-scan first to confirm what’s inside and that the concrete is suitable for anchoring.
Do I need an engineer for doweling?
For structural connections, yes — bar size, spacing, embedment depth, and epoxy selection should follow an engineer’s design. We install to spec and can coordinate with your engineer.
