London ARU guide

ARUs, Mature Trees, and Tree Grants in London, Ontario

The best London ARU lots often have the same thing that makes them complicated: mature trees. If a backyard suite is being planned in Old South, Old North, Wortley, Woodfield, or another canopy-rich neighbourhood, tree preservation and ARU feasibility should be reviewed together before drawings, trenching, or builder pricing get too far ahead.

Run The ARU Audit
Decision guide

Check the property before you spend on plans

Use the lot, loan, rent-cap, and servicing screens to decide whether the next step should be design work, a builder conversation, or more research.

  • Check the address
  • Review the loan rules
  • Confirm the rent math
  • Budget the hidden costs

Why Trees Belong In The ARU Feasibility Check

A mature tree can shape where the ARU goes, how services reach it, how construction equipment enters the yard, and whether the project creates by-law risk. London expects protected trees and root areas to be handled carefully during construction, so tree review belongs beside zoning, setbacks, lot coverage, and servicing.

  • Map large trees before choosing the backyard-suite footprint.
  • Avoid treating the shortest trench route as the best route if it crosses a root zone.
  • Coordinate arborist advice before the site plan becomes expensive to change.

The 40 cm And 50 cm Tree Thresholds Matter

Tree planning should happen before removal or heavy pruning is assumed. London Tree Grant frames the practical homeowner distinction clearly: mature-tree conservation support may start around the 40 cm DBH threshold, while larger protected trees can trigger stricter removal-permit concerns. If your ARU layout depends on changing a mature tree, measure first and get qualified advice before committing to a design.

The ARU question is not only 'can the unit fit?' It is also 'can the unit fit without turning a healthy canopy asset into a project risk?'

Canopy Data Can Help Prioritize Preservation

London's Forest City identity matters most in neighbourhoods where mature canopy is already under pressure. The London Tree Grant canopy dashboard gives homeowners a simple way to think about neighbourhood canopy health before a backyard project removes shade, privacy, and long-term property value.

  • Use canopy context when weighing tree preservation against ARU placement.
  • Prioritize pruning and cabling where tree health can be protected without compromising the unit.
  • Treat removal as a last-resort planning question, not the default first move.

A Better Combined Site-Plan Workflow

For mature London lots, the clean workflow is simple: screen the ARU, map the trees, check the grant/rebate path, then design the servicing route. This keeps the mature-neighbourhood ARU plan and tree-care plan from fighting each other late in the process.

  • Run the ARU zoning and lot-fit screen.
  • Measure major trees and note canopy, trunk location, and likely root areas.
  • Check London Tree Grant before pruning or preservation work begins.
  • Design the ARU footprint and utility route around the tree constraints that remain.

FAQ

Common questions, answered plainly

Should I check tree issues before designing a backyard ARU?

Yes. Mature trees can affect the ARU footprint, trench route, construction access, permit risk, and total budget. Tree review should happen before the design becomes expensive to revise.

Can tree grant planning and ARU planning happen together?

Yes. If a mature tree affects the ARU site plan, it makes sense to coordinate the ARU feasibility screen with qualified tree-care advice and any available preservation rebate path.

Does a tree grant replace London ARU zoning approval?

No. Tree grant or pruning rebate eligibility does not approve an ARU. The backyard suite still needs zoning, setbacks, lot coverage, permits, servicing, and inspections.

Screen The ARU And Tree Plan Together

Use the ARU audit first, then check London Tree Grant if mature trees affect the build area, service route, or construction access.

Run The ARU Audit