What Happens to the Trees When You Demolish a House in Oakville

The rule in one line

Oakville's Private Tree Protection By-law says you need a permit to remove any tree on private property with a trunk 15 centimetres or more across at breast height, measured 137 centimetres above the ground. If you're not sure, wrap a tape around the trunk: about 47 centimetres around is the cut-off.

Why a teardown brings an arborist in

When a tree removal is tied to a demolition, the town asks for an arborist report from a certified arborist. The report looks at every regulated tree on the lot, and often the ones close to it on neighbouring properties, and says which can stay and how to protect them.

• Boulevard trees belong to the town and have their own process.
• Boundary trees need the neighbour's written consent to remove.
• Dead and high-risk trees still need a permit, though fees are waived.

How trees are protected during the work

For each tree that stays, the arborist sets a protection zone. Hoarding goes up around it before any machine arrives, and it stays up until the builder is done. Inside that zone, there's no stockpiling of debris or soil, no parking and no machine tracking.

Roots are the real concern. Most of a tree's roots are in the top layer of soil and spread well past the branches, so compaction from heavy equipment can do more harm than a broken limb.

How trees change the demolition

On a narrow lot, a tree in the side yard can decide which side the excavator comes in from. A tree close to the house can mean part of the foundation is removed with a smaller machine or by hand. It's normal, and it's much easier to plan for up front than to deal with on the day.

It can also change what happens after the demolition. If a big tree sits near where the new foundation will go, your builder and arborist may decide on a different footprint, a different excavation method or a smaller machine for part of the dig. Those are design decisions, and they're much easier to make on paper than in the field.

When it makes sense to bring in a professional

You'll need an arborist for the report. You'll also want your demolition contractor to see the lot with the arborist's plan in hand, so they can confirm how machines will get in and where debris can go.

It's worth doing before your builder finalises the footprint of the new house, because that's when there's still room to adjust. Our residential demolition and site clearing crews work to the tree protection plan on every lot.

Bring your arborist's report to the site visit if you have it. If you don't yet, your demolition contractor can still point out which trees are likely to shape the work, so you know what to ask the arborist about.

The takeaway

Trees and teardowns can live together. Know which trees are regulated, get the arborist report into your permit package, put hoarding up before anything moves, and plan machine routes around root zones. Bolan Group Demolition Oakville is glad to walk your lot with your plan. Book a free estimate.