Where We Work
Paradise Valley has the most demanding residential regulations in the Valley: a 25% floor area ratio, an Open Space Criteria height plane on top of the height limit, and a Hillside Building Committee that reviews projects before a permit application can be filed. Designing here means designing to that framework from the first sketch.
Two things decide a Paradise Valley project before design begins: whether the parcel is hillside, and how much floor area the 25% FAR leaves you. Hillside status routes you through committee review before permit application and replaces the flat height limit with a plane following natural grade. On flatland, the Open Space Criteria "imaginary tent" often constrains the house more than the height limit does.
Flatland Standards
Total floor area may not exceed 25% of lot area, except in R-10 zoning. It counts area under the roof of the main building, second storeys, all accessory buildings including gazebos and ramadas, certain courtyards, and eaves. Fully subterranean portions are excluded — which is why basements are a common strategy here.
Total square footage of all accessory buildings cannot exceed 50% of the ground area of the main residence, and accessory structures are capped at 16 feet including chimney.
Measured from Lowest Natural Grade or Lowest Unrestored Excavated Grade, whichever is lower.
Applied in addition to the height limit. No building may penetrate a plane beginning 16 feet above the 20-foot setback line and rising toward the centre of the lot at 20%. In practice:
Chimneys may not penetrate the plane. On most lots this is what actually shapes the massing — the height limit is theoretical until you are well inside the setbacks.
Setback certification is required at pre-slab inspection when a structure is within 3 feet of the minimum setback; height certification at stem inspection when within 2 feet of maximum height. Both must be sealed by an Arizona-registered engineer or land surveyor.
Hillside Parcels
To all land in the mapped Hillside Development Area, and to all land where natural terrain under the building pad has a slope of 10% or greater — whether mapped or not. The one exemption is a 10%-plus slope created by a natural wash on otherwise non-hillside land.
A pre-application review is mandatory for every hillside application. From there a project is assigned to Administrative Hillside Chair Review, Combined HBC Review, Concept Plan Review or Formal HBC Review. The committee has six members — three Council-appointed citizens and three rotating Planning Commissioners — and meets as needed.
Additions and accessory structures qualify for Chair review only if they do not exceed or increase main residence height, add more than 100 SF of footprint, create more than 100 SF of additional disturbed area, add more than 15 linear feet of wall, propose significant added exterior lighting, or create significant adverse visual impact.
| Building-site slope | Allowable disturbance |
|---|---|
| 10% | 60.0% |
| 15% | 34.1% |
| 20% | 19.9% |
| 25% | 13.1% |
| 30% | 10.6% |
| 40% | 10.0% |
| 60% | 8.0% |
| 80%+ | 4.0–6.0% |
Source: Hillside Building Committee
Cited from Town-published materials as of 2026. Per-district setbacks vary across R-175, R-43, R-35/A, R-18/A and R-10 and should be confirmed against the current Zoning Ordinance for your parcel — E-Project does this at feasibility.
Other Requirements Worth Budgeting For
Required any time more than 12 linear feet of wall or fence, or 12 SF of roof or slab, is removed — and must be obtained before the building permit issues.
Sealed by an Arizona-registered civil engineer on any single-family home, where 999 SF or more of impervious area is added, or where work value exceeds $500,000.
Required in all new structures, and in existing structures undergoing a 50% structural addition, alteration or repair, or affecting 50% or more of the building.
9.0% of the building permit fee on new construction or remodels valued at $500,000 or more; a haul permit applies when more than 100 cubic yards of dirt moves on or off site.
Town dust control plan where disturbance is under about 4,356 SF; a Maricopa County dust control permit above that, unless owner-builder.
A building permit is required for any structure over 8 inches requiring a fixed ground location — and a separate application is required for each type of structure.
If the parcel is in the mapped Hillside Development Area, or if natural terrain under the building pad slopes 10 percent or more anywhere — mapped or not — then Article XXII applies and the Hillside Building Committee is involved. A pre-application review is mandatory for all hillside applications, and the Town's guidance is that hillside committee review happens before applying for a building permit. New homes, remodels and additions, solar installations, accessory structures such as ramadas, and new pools all go through it.
On flatland, maximum height measured from lowest natural grade or lowest unrestored excavated grade, whichever is lower, is 24 feet on lots under 3 acres, 26 feet on lots of 3 to under 4 acres, and 30 feet including chimneys on lots of 4 acres or more. On top of that, the Open Space Criteria imposes an imaginary plane beginning 16 feet above the 20-foot setback line and rising toward the centre of the lot at 20 percent — roughly 16 feet at the 20-foot setback, 20 feet at 40 feet, 24 feet at 60 feet. On hillside parcels a 24-foot plane paralleling pre-development natural grade governs instead, with an overall 40-foot maximum.
Total floor area shall not exceed 25 percent of the lot area, except in R-10 zoning. That figure includes area under the roof of the main building, second storeys, all accessory buildings such as gazebos and ramadas, certain courtyards, and eaves. Fully subterranean portions are excluded. Separately, the total square footage of all accessory buildings cannot exceed 50 percent of the ground area of the main residence, and accessory structures are capped at 16 feet in height including chimney.
An administrative Hillside Chair review is available for accessory structures and additions that do not exceed or increase the main residence height, do not increase the existing building footprint by more than 100 square feet, do not create more than 100 square feet of additional disturbed area, do not increase wall length by more than 15 linear feet, do not propose significant added exterior lighting, and do not create significant adverse visual impact. Anything beyond that goes to a fuller review track.
The Town states that initial review and each subsequent review may take up to 15 business days, with an additional 3 to 5 business days to process the permit after approval. Deferred truss calculations, revisions and re-stamps are also up to 15 business days. In-house plan review fee is 65 percent of the building permit fee and covers up to two reviews; additional reviews are billed hourly. All permit applications are submitted electronically through the Town's Citizen Portal.
FAR, the Open Space Criteria plane and hillside status decide the project. Have them checked before you commit.
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