Tree removal permit guide — Pittsburgh, PA

Most Pittsburgh tree-removal projects fall into one of four scenarios with very different permit implications:

Scenario 1: Flat-lot, private property, away from right-of-way. The most common case. Pittsburgh does not have a citywide DBH-based residential tree-protection ordinance, so tree removal in this scenario typically does not require a city permit. The contractor still needs to be licensed and insured; the homeowner still needs to verify HOA covenants if applicable; but the city itself doesn't require a removal permit.

Scenario 2: Hillside Overlay zone. Pittsburgh's Hillside Overlay applies to lots with slope generally exceeding 25%. The overlay requires erosion-control review for any work that disturbs the slope — including tree removal that could affect slope stability. Removing trees on Hillside Overlay lots typically requires submitted plans, an erosion-control approach, and sometimes a structural engineer's assessment. Many neighborhoods are largely or entirely in the Hillside Overlay: Mt. Washington, Beechview, Brookline, Polish Hill, the South Side Slopes, parts of Squirrel Hill, the West End, parts of Greenfield. Verify with the Department of City Planning.

Scenario 3: Right-of-way trees. Trees in the Pittsburgh right-of-way (typically the strip between sidewalk and street, but verify with the city) are managed by DPW Forestry. Removing or significantly pruning right-of-way trees requires a permit from DPW Forestry, regardless of who is paying for the work. The city itself maintains and removes right-of-way trees in many cases; private removal of a right-of-way tree by a homeowner-hired contractor is generally not permitted without DPW approval.

Scenario 4: Construction-tied removal. Any tree removal tied to a building permit (additions, ADUs, garages, decks over a certain size, driveway expansions, major site work) is reviewed as part of the building permit process. The Department of City Planning evaluates proposed tree removal in the context of zoning, the Hillside Overlay, drainage, and other site factors. Significant tree removal as part of construction can trigger additional environmental review.

The Hillside Overlay is the most consequential tree-removal regulator in Pittsburgh, even though it doesn't directly target trees. The overlay is part of the city's effort to prevent landslides, manage stormwater, and protect steep-slope ecosystems.

What the overlay covers: lots with slopes generally exceeding 25% within the designated overlay districts. The slope is measured across the lot — even a partially flat lot with a steep section can be in the overlay for that section. Pittsburgh's topography means many neighborhoods include large portions of overlay-zoned land.

What the overlay requires: any earth-disturbing activity (which includes removing trees with significant root systems on steep slopes) requires erosion-control review and approved plans. The plans are submitted to the city and may require a registered surveyor, a soil scientist, or a structural engineer depending on scope.

What homeowners often miss: even healthy trees on steep slopes have a stabilization function. Removing them changes the slope's stability profile and can trigger landslide risk that wasn't there before. Pittsburgh has well-documented landslide history, and the Hillside Overlay reflects that. Removing trees on slope without proper review and replacement planning can lead to property damage and liability that far exceeds the cost of doing it right.

The practical workflow on a Hillside Overlay lot: 1. ISA-certified arborist assesses the trees 2. If trees can stay, structural pruning + cabling is often the right path 3. If trees must come down, get the city Hillside Overlay review started early — it can take 6-12 weeks for review of significant work 4. Replacement plantings + erosion-control measures (silt fencing during work, replanting after) are typically required 5. Use contractors with documented Hillside experience

Pittsburgh DPW Forestry manages the city's right-of-way trees — typically trees in the parkway between sidewalk and street, but verify the specific right-of-way for your property.

What DPW Forestry handles: maintenance of city right-of-way trees, removal of dead or hazardous right-of-way trees, planting new street trees, and approvals for any private work on right-of-way trees.

What homeowners cannot do: remove or significantly prune a right-of-way tree without DPW Forestry approval. This applies even if the tree is causing problems for the adjacent private property (lifting sidewalk, blocking driveway sight lines, etc.) — the homeowner reports the problem to DPW Forestry, and the city decides on action.

What homeowners can do: report problems with right-of-way trees through 311 or directly to DPW Forestry. Request planting of a new street tree (often subsidized or city-funded). Request specific routine maintenance.

The permit process for private work on right-of-way trees is narrow — most maintenance is city-handled. If you need to remove a right-of-way tree as part of a private project (driveway widening, utility work, etc.), the DPW Forestry approval is the binding step. Plan ahead; right-of-way tree approvals can take 4-8 weeks.

When tree removal is part of a building or zoning permit, the Department of City Planning evaluates the removal in the broader site context. The review includes:

Hillside Overlay implications. If the construction is on overlay-zoned land, the tree removal is reviewed for slope-stability and erosion-control implications.

Drainage and stormwater. Pittsburgh has stormwater regulations that intersect with tree removal. Trees absorb significant water; removing trees can trigger stormwater-management requirements (rain gardens, infiltration trenches, etc.) for the new construction.

Zoning compatibility. Some Pittsburgh zoning districts have specific tree or vegetation requirements that affect what can be removed.

Replacement requirements. The city may require replacement plantings as part of the permit conditions, particularly in Hillside Overlay zones or where significant tree canopy is being lost.

The practical workflow: engage your contractor and an arborist early in the design phase. Tree-protection plans and replacement plans are easier to develop alongside the building plans than after the city flags issues during permit review.

Pittsburgh's tree-removal rules apply within the city limits. Surrounding jurisdictions in Allegheny County have their own rules:

Municipalities in Allegheny County (Mt. Lebanon, Bethel Park, Upper St. Clair, Fox Chapel, Sewickley, McCandless, Ross, etc.). Many have their own tree-protection ordinances, often less strict than Pittsburgh's Hillside Overlay framework but sometimes adding species-specific or DBH-based protections that Pittsburgh proper does not have.

Allegheny County (unincorporated areas). The county itself has limited tree-protection regulation; most regulation is at the municipal level.

Conservation districts. The Allegheny County Conservation District administers erosion-and-sediment control regulations that intersect with tree removal on slopes. Some major projects require conservation-district review in addition to municipal permits.

PA DCNR (state forest service). Pennsylvania has limited state-level residential tree regulation. State protections apply mostly to specific species (American chestnut, certain elm cultivars) and to forest-conservation programs that don't directly affect residential removal.

The practical implication: don't assume rules from one municipality apply across Allegheny County. Verify each property's actual jurisdiction.