Patio rules & permits in Montgomery Township, PA

Site plan and setbacks

A patio permit application must include a site plan showing the patio's placement on the property. Setback requirements vary by zoning district, and a patio (like a deck) that does not meet the accessory standards must be located within the building envelope — the district's full required yards.

Source: Montgomery Township Code — Zoning, Art. XXI, Miscellaneous Provisions (eCode360) confirm with township

Impervious surface ratio

A patio adds impervious surface. For a lot used for a single-family detached dwelling (or agriculture) the maximum impervious surface ratio is 30%; some other uses are capped at 35%. Confirm your lot's current coverage before sizing the patio.

Source: Montgomery Township Code — Zoning, R-1 Residential District (eCode360) confirm with township

Call 811 before you dig

Pennsylvania law requires calling PA One Call (dial 811 or visit pa1call.org) at least 3 business days before any digging — including fence post holes — so underground utilities can be marked for free.

Source: Pennsylvania One Call System (PA 811)

Patio permits & impervious coverage (PA UCC + local zoning)

A flat, at-grade patio (concrete, pavers, brick, or stone with no roof and no structural frame) generally does NOT need a Uniform Construction Code building permit — a slab on grade isn't a "structure" under the code. But almost every municipality still requires a zoning permit to check setbacks and, especially, impervious-surface coverage, and many add stormwater requirements for new impervious area.

• Zoning permit: nearly always required so the township can confirm the patio meets property-line setbacks and does not push the lot over its impervious-coverage limit.
• Impervious coverage: a patio adds impervious surface, which is capped as a percentage of the lot by zoning district; going over the cap requires a variance or a smaller/permeable design.
• Stormwater: many townships require stormwater best-management practices once new impervious area passes a threshold (often around 1,000–1,500 sq ft) — permeable pavers or a small infiltration bed can help.
• When a building permit IS needed: a patio becomes permit-worthy if it has a permanent roof or cover (pergola with a solid roof, pavilion), is raised on a structural frame, or includes electrical, gas, or plumbing (an outdoor kitchen or gas fire feature).
• Call 811 before you dig: excavating the gravel base still counts as digging, so PA One Call applies.

Whether a patio is reviewed as a zoning permit or a building permit, and the exact impervious-coverage cap and stormwater threshold, are set locally — confirm both with your township before sizing the patio.

Source: PA Uniform Construction Code — scope of residential building permits

Property lines

You are responsible for building on your own property. If you are not certain where your property line is, find your official plot plan (often included with closing documents), check the county GIS map, or hire a surveyor. Building over the line can mean rebuilding the fence at your own cost.

Easements

Drainage, utility, and access easements commonly cross residential lots. Most townships restrict or prohibit fences in easements, and a utility can remove a fence built in one. Your deed and recorded plot plan show easements.

HOA rules

If your home is in a homeowners association, HOA rules apply on top of township rules and are often stricter (style, color, height, approval process). Get HOA approval in writing before applying for the township permit.

Corner lots and sight triangles

Corner lots usually face extra restrictions near intersections so drivers can see cross traffic ('clear sight triangles'). If you are on a corner, ask the township specifically about street-side fence rules.