Buying a house with large trees: what to check before you commit

Big trees give a home shade and privacy. They can also come with risk, upkeep bills and bylaw limits on what you can build later. Before buying a house with large trees, look for visible warning signs, find out whether any of them are protected, and think about having a certified arborist inspect them.

A home inspector looks at the house. Usually nobody looks closely at the trees. That's a real gap in Greater Victoria, where mature Garry oaks, Douglas-firs and big ornamentals are everywhere.

Why do trees matter when you buy a house?

Trees affect a purchase in four main ways.

The first is value. Healthy, well-placed trees are part of what makes many properties appealing, but a tree in poor condition may need costly work soon after you move in.

Then there's risk. A large tree with a defect over a roof, driveway or neighbour's yard is a liability, and it becomes yours with the property.

Insurers may also ask about trees near the house. We can't give insurance advice, so ask your broker how they view large trees before you finalize coverage.

Last, think about what you might build. If you hope to add a suite, garage, addition or new driveway, a protected tree nearby can limit where and how you build. It can also mean permits, arborist reports and protection fencing.

What warning signs can a buyer spot?

You don't need to be an arborist to notice some red flags. UC IPM lists several visible signs of a hazardous tree:

• Mushrooms, brackets or other fungal growths on the trunk, roots or base
• Cracks or splits in the trunk or where large limbs join
• Cavities or hollows in the trunk or at the base
• Dead or dying branches, especially large ones over the house
• Wounds or cankers (sunken, dead patches of bark)
• A trunk that leans, especially if the lean looks new
• Cracks or lifted soil near the base of the tree

Some problems, like internal decay or root damage, can't be seen from outside. So a tree with no obvious red flags isn't necessarily sound.

Watch, too, for recent digging, new paving or fill soil near large trees. Construction in the root zone can hurt a tree for years after the crew has gone.

How can protected trees limit your future plans?

Many municipalities in Greater Victoria and the Cowichan Valley have tree protection bylaws, and the rules differ a lot from place to place. A bylaw may protect trees by species, trunk size or location. Many also cover work near a protected tree, as well as removing it.

The City of Victoria, for example, says you may need a permit to work within the protected root zone of a protected tree, even if you're leaving the tree standing. So a future addition, patio or driveway could need an arborist report, a tree permit and protection measures before construction starts.

The details vary between municipalities and get amended from time to time, so don't rely on general rules. Check the guide for the area you're buying in:

• Saanich, Victoria, Oak Bay, Esquimalt
• Central Saanich, North Saanich, Sidney
• Langford, Colwood, View Royal, Metchosin, Highlands
• Sooke, Juan de Fuca
• Duncan, Cowichan Valley

There's also a bylaw comparison table for the region on our consulting and permitting page. When in doubt, call the municipality.

Should you get a pre-purchase tree assessment?

It's worth considering if there are large trees near the house, trees you'd want to remove, or building plans that involve the yard. A certified arborist can tell you what shape the trees are in and how much risk they pose. They can also tell you how the local bylaw might affect your plans.

Options at Oakstead (from prices, plus GST):

Timing matters. Ask your realtor or lawyer how to fit a tree assessment into your offer conditions and inspection period, since we can't advise on contract terms.

Oakstead is consulting only. We don't cut or remove trees, so we have nothing to sell you once the assessment is done. If work is needed, we refer you to vetted local partners and take no referral fees.

What questions should you ask the seller and realtor?

• Has any tree work been done recently? Is there an invoice or arborist report?
• Have any trees been removed? Was a permit issued?
• Are any trees on the property protected under the local bylaw?
• Has any tree or large limb failed or caused damage before?
• Are there any disputes or agreements with neighbours about trees?
• Have there been insurance claims involving trees? (Your broker or lawyer can advise on what to ask here.)
• Was there construction near any large trees, and was an arborist involved?
• Are there tree permit conditions or securities still in place from past work?

Printable buyer checklist

Take this list to a showing, or work through it before you remove conditions:

1. Note every large tree within striking distance of the house, garage or driveway.
2. Look up at each tree for dead or broken branches.
3. Check trunks for cracks, splits and cavities.
4. Look for mushrooms or brackets on trunks, roots and at the base.
5. Note any trunk that leans, and check the ground on the opposite side for cracks or lifting.
6. Look for recent digging, fill, paving or trenching near trees.
7. Note trees close to the property line or overhanging a neighbour.
8. Note trees near power lines.
9. Ask the seller for any arborist reports, invoices or tree permits.
10. Check the municipal guide for whether trees on the lot may be protected.
11. Write down any future plans (addition, suite, driveway, garden) that could affect trees.
12. Ask your insurance broker how they treat large trees near the house.
13. Ask your realtor about timing for a tree assessment within your conditions.
14. Book a certified arborist if any of the above raises a concern.

Buying a property with big trees? Book a pre-purchase tree assessment before your subjects come off, or request a consultation.