Webster · ADU cost
What it costs to build an ADU in Webster, NY
An 800 sq ft accessory dwelling unit in Webster runs roughly $200k–260k, or about $249–327/sq ft, and that per-square-foot figure sits deliberately above the $204–268/sq ft a full house costs here. An ADU still needs one whole kitchen, one whole bath, its own service panel and its own heating plant no matter how small you draw it, and those costs do not shrink with the floor plan, so they land on half the square footage and push the rate up. Whether the village will let you build one is a separate question from what it costs, and it gets answered parcel by parcel rather than townwide, since the Village of Webster maps 4 districts that treat accessory units differently from one another, so read the table below as a starting point rather than a verdict.
ADU cost by size in Webster
Standard finish, slab on grade, on a flat and clear part of the lot, general-contractor margin included. These are structure costs at Monroe County pricing, before the service and septic work a second dwelling can trigger.
| Size | Type | $ / sq ft | Estimated total |
|---|---|---|---|
| 400 sq ft | Studio | $331–$433 | $130k–175k |
| 600 sq ft | One bedroom | $276–$362 | $165k–215k |
| 800 sq ft | One bedroom, larger | $249–$327 | $200k–260k |
| 1,000 sq ft | Two bedroom | $233–$305 | $235k–305k |
400 sq ft — One room plus a bath. Garage conversions and small backyard cottages land here.
600 sq ft — The most common detached build - a real bedroom, full kitchen, one bath.
800 sq ft — Room for a proper living area. Still a single bath and one kitchen.
1,000 sq ft — About as large as most codes allow an accessory unit to go.
Why the rate is higher than a house
The systems below are priced for an 800 sq ft unit. The middle column is what each system would cost if it simply shrank with the floor plan; the left column is what it actually costs once you account for the equipment a dwelling needs one of regardless of size. The gap between the two columns is the whole reason small builds price the way they do.
| System | $ / sq ft in an ADU | If it scaled with floor area | Fixed per unit |
|---|---|---|---|
| Site work | $7–$11 | $7 | — |
| Foundation | $16–$23 | $16 | — |
| Framing | $25–$32 | $25 | — |
| Envelope - roof, siding, windows | $32–$41 | $32 | — |
| Plumbing | $28–$34 | $16 | 55% |
| Electrical | $18–$24 | $13 | 35% |
| HVAC | $23–$28 | $15 | 45% |
| Insulation | $7–$9 | $7 | — |
| Interior finishes | $32–$43 | $27 | 15% |
| Millwork & cabinetry | $18–$28 | $11 | 55% |
The fixed-per-unit share is a modeling assumption, not a figure from the code: it is our estimate of how much of each system's budget buys equipment a dwelling needs exactly one of - a kitchen rough-in, a bath group, a service panel, a heating plant - and therefore does not shrink when the unit does. Site work, foundation, framing, envelope and insulation are treated as scaling straight with floor area, which understates the premium slightly, because a small building carries more envelope per square foot of floor than a large one.
What the Webster code says about accessory units
Whether you can build one, and how large, is decided by the district your parcel sits in rather than by the town as a whole. The table shows how each mapped district treats ADUs alongside the lot and setback standards a second unit still has to fit inside. District boundaries and conditions vary, so treat it as a starting point and confirm the district that applies to your parcel.
| District | Min lot | Setbacks F / S / R | Max height | ADU |
|---|---|---|---|---|
| Residential R-1-13.6 District — 13,600 sf (0.31 acres) minimum lot area, front yard 40 ft, rear yard 40 ft, side yards 20 ft total with neither less than 8 ft at the front and rear building line, maximum height 30 ft and maximum lot coverage 20%. The village's largest-lot district and SINGLE-FAMILY ONLY — § 175-10 permits single-family dwellings and their accessory uses, then a site-plan set (schools, churches, libraries, fire stations, municipal offices, telephone exchanges, utility substations, private swimming pools); no two-family, no townhouse, no accessory dwelling unit. THE DISTRICT STATES NO MINIMUM LOT WIDTH, which is unusual here — R-1-9.6, R-2-9.6 and RM all state 75 ft at the front building line and this one states none, so minLotWidthFt is null by design rather than unread. TWO TRAPS. (1) THE SUBDIVISION RULE IS A SECOND, HIGHER MINIMUM: § 175-11A(2) requires that 50% IN NUMBER of the lots appearing on any subdivision plan submitted be at least 16,000 sf, so a subdivider cannot build the whole plan at 13,600 sf — half the lots must be ~18% larger, and the recorded 13,600 sf is the floor for an individual lot, not the achievable average across a plan. (2) THE FRONT YARD IS CONTEXTUAL: where principal structures front the same street within 300 FEET of either side line, the required depth becomes the AVERAGE of the nearest such setbacks on each side (or the average of that setback and 40 ft where there is a structure on one side only), never less than 20 ft. On an infill lot in an established block the real front yard is a function of the neighbours, not of this figure. The side-yard rule also has a narrow-lot reduction for lots under 70 ft wide held in separate ownership at the effective date: the 20 ft total reduces by 1 ft for each foot of width under 70, floored at 12 ft total, and once the total falls below 16 ft THE TWO SIDE YARDS MUST BE EQUAL. Lot coverage counts ALL buildings including accessory buildings. Height is 30 ft for dwellings and structures attached to them, 18 ft for detached garages and 10 ft for accessory buildings. | 0.3122 ac | 40 / 8 / 40 ft | 30 ft | No |
| Residential R-1-9.6 District — 9,600 sf (0.22 acres) minimum lot area with 75 ft of lot width at the front building line, front yard 40 ft, rear yard 40 ft, side yards 16 ft total with neither less than 6 ft at the front and rear building line, maximum height 30 ft and maximum lot coverage 25%. The village's standard single-family district: § 175-12 permits single-family dwellings and their accessory uses plus the same site-plan set as R-1-13.6, with no two-family, townhouse or accessory dwelling unit. It is the same lot size as R-2-9.6 and RM — the three districts share the 9,600 sf / 75 ft baseline and differ only in what may be built on it, so THE DISTRICT NAME AND NOT THE LOT SIZE IS WHAT DETERMINES WHETHER A SECOND UNIT IS REACHABLE. Against R-1-13.6 this district trades 4,000 sf of lot for 5 percentage points of coverage (25% vs 20%) and 4 ft of total side yard. THE FRONT YARD CARRIES THE SAME 300-FOOT CONTEXTUAL AVERAGING OVERRIDE as every other residential district here (average of the nearest principal structures fronting the same street within 300 ft of either side line, floored at 20 ft), amended 6-9-1994 by L.L. No. 2-1994. The narrow-lot side-yard reduction is calibrated differently from R-1-13.6 and must not be carried across: it triggers below 60 FT of width (not 70), reduces the total by SIX INCHES per foot under 60 (not one foot), floors at 10 ft total (not 12), and forces equal side yards once the total falls below 12 ft (not 16). Lot coverage counts ALL buildings including accessory buildings. Height is 30 ft for dwellings and attached structures, 18 ft for detached garages, 10 ft for accessory buildings. | 0.2204 ac | 40 / 6 / 40 ft | 30 ft | No |
| Residential R-2-9.6 District — 9,600 sf (0.22 acres) minimum lot area with 75 ft of lot width at the front building line for a single-family dwelling, front yard 40 ft, rear yard 40 ft, side yards 16 ft total with neither less than 6 ft, maximum height 30 ft and maximum lot coverage 25%. THE RECORDED FIGURES ARE THE SINGLE-FAMILY ROW — this district's value is that it also reaches two-family dwellings and townhouses, and each carries its own larger standard. A TWO-FAMILY DWELLING NEEDS 18,000 SF AND 100 FT OF WIDTH — nearly double the single-family lot — and its total side-yard width increases by 10 ft with neither side less than 10 ft at the front and rear building lines. TOWNHOUSES ARE SIZED BY DENSITY, NOT BY LOT: 2,000 sf per dwelling unit, a minimum of ONE ACRE per townhouse group, and a hard cap of EIGHT UNITS PER ACRE — so the binding constraint on a townhouse scheme is the 8 du/acre cap and the one-acre group minimum, not the 9,600 sf district minimum, and sizing a townhouse yield off the district minimum overstates it by roughly 5x. Townhouse side yards are 40 FT to adjacent properties, with separate buildings in a development kept 20 ft apart or the height of the taller adjacent building, whichever is greater. BOTH THE TWO-FAMILY AND THE TOWNHOUSE ARE 'CONTROLLED SITE USES' SUBJECT TO SITE PLAN REVIEW AND APPROVAL UNDER ARTICLE XIV — they are not by-right, so a second unit here is discretionary. § 175-14 otherwise permits single-family dwellings and their accessory uses by right plus the standard site-plan set; there is no accessory dwelling unit. The front yard carries the same 300-foot contextual averaging override, floored at 20 ft, and the narrow-lot side-yard reduction matches R-1-9.6 (below 60 ft of width, six inches per foot, floor of 10 ft total, equal yards below 12 ft). Lot coverage counts all buildings including accessory buildings. Height is 30 ft for dwellings and attached structures, 18 ft detached garages, 10 ft accessory buildings. | 0.2204 ac | 40 / 6 / 40 ft | 30 ft | No |
| Residential RM District — 9,600 sf (0.22 acres) minimum lot area with 75 ft of lot width for a single-family dwelling, front yard 40 ft, rear yard 40 ft, side yards 16 ft total with neither less than 6 ft, maximum height 35 ft and maximum lot coverage 25%. THE VILLAGE'S ONLY MULTIFAMILY DISTRICT AND THE ONE THAT MATTERS FOR YIELD. § 175-16 reaches two-family AND MULTIPLE-FAMILY dwellings, townhouses and condominiums, all as controlled site uses under Article XIV site plan review, plus state-regulated multiple residences for the aged and infirm. THE MULTIFAMILY FORMULA IS THE HEADLINE: 20,000 sf for the first two units PLUS 3,000 SF FOR EACH ADDITIONAL UNIT, with a 150 ft minimum lot width — so a one-acre parcel (43,560 sf) supports about 9 units and the marginal unit costs only 3,000 sf, making the yield curve flatten sharply above the base. Two-family dwellings take 18,000 sf and 100 ft of width; townhouses take 2,000 sf per unit with a one-acre group minimum and an 8 du/acre cap. THE HEIGHT FIELD IS THE BIGGEST TRAP IN THIS DISTRICT AND THE RECORDED 35 FT IS THE SINGLE- AND TWO-FAMILY/TOWNHOUSE FIGURE ONLY: § 175-17D states that THERE IS NO LIMIT ON THE HEIGHT OF MULTIPLE-FAMILY DWELLINGS, CONDOMINIUMS OR NONRESIDENTIAL STRUCTURES. A 40 ft building owes 80 ft to each side and rear line. For nonresidential structures each foot above 35 ft adds 2 ft to the total side-yard width and 1 ft to the front-yard depth. Note the RM height for the ordinary house case (35 ft) is 5 ft taller than the three other residential districts (30 ft). The front yard carries the same 300-foot contextual averaging override, floored at 20 ft. Lot coverage counts all buildings including accessory buildings. No accessory dwelling unit exists here or anywhere in the village. | 0.2204 ac | 40 / 6 / 40 ft | 35 ft | No |
Size limits on record in Webster
Where the code states a size cap, it decides which row of the cost table above actually applies to you. These are the caps recorded for Webster:
- Residential R-1-13.6 District — 13,600 sf (0.31 acres) minimum lot area, front yard 40 ft, rear yard 40 ft, side yards 20 ft total with neither less than 8 ft at the front and rear building line, maximum height 30 ft and maximum lot coverage 20%. The village's largest-lot district and SINGLE-FAMILY ONLY — § 175-10 permits single-family dwellings and their accessory uses, then a site-plan set (schools, churches, libraries, fire stations, municipal offices, telephone exchanges, utility substations, private swimming pools); no two-family, no townhouse, no accessory dwelling unit. THE DISTRICT STATES NO MINIMUM LOT WIDTH, which is unusual here — R-1-9.6, R-2-9.6 and RM all state 75 ft at the front building line and this one states none, so minLotWidthFt is null by design rather than unread. TWO TRAPS. (1) THE SUBDIVISION RULE IS A SECOND, HIGHER MINIMUM: § 175-11A(2) requires that 50% IN NUMBER of the lots appearing on any subdivision plan submitted be at least 16,000 sf, so a subdivider cannot build the whole plan at 13,600 sf — half the lots must be ~18% larger, and the recorded 13,600 sf is the floor for an individual lot, not the achievable average across a plan. (2) THE FRONT YARD IS CONTEXTUAL: where principal structures front the same street within 300 FEET of either side line, the required depth becomes the AVERAGE of the nearest such setbacks on each side (or the average of that setback and 40 ft where there is a structure on one side only), never less than 20 ft. On an infill lot in an established block the real front yard is a function of the neighbours, not of this figure. The side-yard rule also has a narrow-lot reduction for lots under 70 ft wide held in separate ownership at the effective date: the 20 ft total reduces by 1 ft for each foot of width under 70, floored at 12 ft total, and once the total falls below 16 ft THE TWO SIDE YARDS MUST BE EQUAL. Lot coverage counts ALL buildings including accessory buildings. Height is 30 ft for dwellings and structures attached to them, 18 ft for detached garages and 10 ft for accessory buildings.The two-family route carries a real dimensional penalty: 18,000 sq ft and 100 ft of width against the 9,600 sq ft / 75 ft single-family baseline
- Residential R-1-9.6 District — 9,600 sf (0.22 acres) minimum lot area with 75 ft of lot width at the front building line, front yard 40 ft, rear yard 40 ft, side yards 16 ft total with neither less than 6 ft at the front and rear building line, maximum height 30 ft and maximum lot coverage 25%. The village's standard single-family district: § 175-12 permits single-family dwellings and their accessory uses plus the same site-plan set as R-1-13.6, with no two-family, townhouse or accessory dwelling unit. It is the same lot size as R-2-9.6 and RM — the three districts share the 9,600 sf / 75 ft baseline and differ only in what may be built on it, so THE DISTRICT NAME AND NOT THE LOT SIZE IS WHAT DETERMINES WHETHER A SECOND UNIT IS REACHABLE. Against R-1-13.6 this district trades 4,000 sf of lot for 5 percentage points of coverage (25% vs 20%) and 4 ft of total side yard. THE FRONT YARD CARRIES THE SAME 300-FOOT CONTEXTUAL AVERAGING OVERRIDE as every other residential district here (average of the nearest principal structures fronting the same street within 300 ft of either side line, floored at 20 ft), amended 6-9-1994 by L.L. No. 2-1994. The narrow-lot side-yard reduction is calibrated differently from R-1-13.6 and must not be carried across: it triggers below 60 FT of width (not 70), reduces the total by SIX INCHES per foot under 60 (not one foot), floors at 10 ft total (not 12), and forces equal side yards once the total falls below 12 ft (not 16). Lot coverage counts ALL buildings including accessory buildings. Height is 30 ft for dwellings and attached structures, 18 ft for detached garages, 10 ft for accessory buildings.The two-family route carries a real dimensional penalty: 18,000 sq ft and 100 ft of width against the 9,600 sq ft / 75 ft single-family baseline
- Residential R-2-9.6 District — 9,600 sf (0.22 acres) minimum lot area with 75 ft of lot width at the front building line for a single-family dwelling, front yard 40 ft, rear yard 40 ft, side yards 16 ft total with neither less than 6 ft, maximum height 30 ft and maximum lot coverage 25%. THE RECORDED FIGURES ARE THE SINGLE-FAMILY ROW — this district's value is that it also reaches two-family dwellings and townhouses, and each carries its own larger standard. A TWO-FAMILY DWELLING NEEDS 18,000 SF AND 100 FT OF WIDTH — nearly double the single-family lot — and its total side-yard width increases by 10 ft with neither side less than 10 ft at the front and rear building lines. TOWNHOUSES ARE SIZED BY DENSITY, NOT BY LOT: 2,000 sf per dwelling unit, a minimum of ONE ACRE per townhouse group, and a hard cap of EIGHT UNITS PER ACRE — so the binding constraint on a townhouse scheme is the 8 du/acre cap and the one-acre group minimum, not the 9,600 sf district minimum, and sizing a townhouse yield off the district minimum overstates it by roughly 5x. Townhouse side yards are 40 FT to adjacent properties, with separate buildings in a development kept 20 ft apart or the height of the taller adjacent building, whichever is greater. BOTH THE TWO-FAMILY AND THE TOWNHOUSE ARE 'CONTROLLED SITE USES' SUBJECT TO SITE PLAN REVIEW AND APPROVAL UNDER ARTICLE XIV — they are not by-right, so a second unit here is discretionary. § 175-14 otherwise permits single-family dwellings and their accessory uses by right plus the standard site-plan set; there is no accessory dwelling unit. The front yard carries the same 300-foot contextual averaging override, floored at 20 ft, and the narrow-lot side-yard reduction matches R-1-9.6 (below 60 ft of width, six inches per foot, floor of 10 ft total, equal yards below 12 ft). Lot coverage counts all buildings including accessory buildings. Height is 30 ft for dwellings and attached structures, 18 ft detached garages, 10 ft accessory buildings.The two-family route carries a real dimensional penalty: 18,000 sq ft and 100 ft of width against the 9,600 sq ft / 75 ft single-family baseline
- Residential RM District — 9,600 sf (0.22 acres) minimum lot area with 75 ft of lot width for a single-family dwelling, front yard 40 ft, rear yard 40 ft, side yards 16 ft total with neither less than 6 ft, maximum height 35 ft and maximum lot coverage 25%. THE VILLAGE'S ONLY MULTIFAMILY DISTRICT AND THE ONE THAT MATTERS FOR YIELD. § 175-16 reaches two-family AND MULTIPLE-FAMILY dwellings, townhouses and condominiums, all as controlled site uses under Article XIV site plan review, plus state-regulated multiple residences for the aged and infirm. THE MULTIFAMILY FORMULA IS THE HEADLINE: 20,000 sf for the first two units PLUS 3,000 SF FOR EACH ADDITIONAL UNIT, with a 150 ft minimum lot width — so a one-acre parcel (43,560 sf) supports about 9 units and the marginal unit costs only 3,000 sf, making the yield curve flatten sharply above the base. Two-family dwellings take 18,000 sf and 100 ft of width; townhouses take 2,000 sf per unit with a one-acre group minimum and an 8 du/acre cap. THE HEIGHT FIELD IS THE BIGGEST TRAP IN THIS DISTRICT AND THE RECORDED 35 FT IS THE SINGLE- AND TWO-FAMILY/TOWNHOUSE FIGURE ONLY: § 175-17D states that THERE IS NO LIMIT ON THE HEIGHT OF MULTIPLE-FAMILY DWELLINGS, CONDOMINIUMS OR NONRESIDENTIAL STRUCTURES. A 40 ft building owes 80 ft to each side and rear line. For nonresidential structures each foot above 35 ft adds 2 ft to the total side-yard width and 1 ft to the front-yard depth. Note the RM height for the ordinary house case (35 ft) is 5 ft taller than the three other residential districts (30 ft). The front yard carries the same 300-foot contextual averaging override, floored at 20 ft. Lot coverage counts all buildings including accessory buildings. No accessory dwelling unit exists here or anywhere in the village.The two-family route carries a real dimensional penalty: 18,000 sq ft and 100 ft of width against the 9,600 sq ft / 75 ft single-family baseline
Costs an ADU adds that a house does not
- Septic and water A second dwelling adds bedrooms to the design flow, which on an unsewered parcel often means expanding or replacing the existing system rather than tapping it. This is the single most common reason an ADU budget moves after design, and it is site-specific enough that no model should quote it - get it evaluated early.
- Utility service RG&E territory. A detached unit needs power run to it, and whether it goes on its own meter or subfeeds the main house changes both the cost and the permit path.
- Access and parking Many codes require an added parking space for the accessory unit, and a detached unit usually needs a driveway extension or a path, both of which count against a lot-coverage or impervious-surface cap.
- Short-term rentalsShort-term rentals prohibited. NO SHORT-TERM RENTAL PROVISION EXISTS IN THE VILLAGE OF WEBSTER, AND THE NEGATIVE IS RECORDED AS 'prohibited' RATHER THAN 'unknown' BECAUSE THE USE LISTS ARE CLOSED AND WERE TESTED AT BOTH LEVELS. Every residential article opens with the words 'only the following structures and uses shall be permitted' (§ 175-10 R-1-13.6, § 175-12 R-1-9.6, § 175-14 R-2-9.6, § 175-16 RM), which makes each list a closed matrix in the same way Scottsville's em-dash table is: a use absent from the list is barred, not merely unaddressed. NONE OF THE FOUR RESIDENTIAL DISTRICTS PERMITS A TOURIST HOME, A BED-AND-BREAKFAST, A ROOMING OR BOARDING HOUSE, A HOTEL OR MOTEL, OR EVEN A HOME OCCUPATION — the residential lists run to single-family dwellings and their accessory uses plus a short site-plan set (schools, churches, libraries, fire stations, municipal offices, telephone exchanges, utility substations, private swimming pools) and, in R-2-9.6 and RM, the additional dwelling types. THE SECOND LEVEL IS ARTICLE XV SPECIAL PERMIT USES (§ 175-42, guid 7738796), WHICH WAS READ IN FULL AND IS SHORT: the 'in any district' list is private clubs, golf courses, parks and playgrounds, hospitals, nursing and proprietary homes, cemeteries, charitable/educational/governmental services, nursery schools, excavation and topsoil removal, and off-site parking. Residential uses are special-permitted only in the NB and CB business districts, and multiple-family dwellings only in GI. NO LODGING OR TRANSIENT USE APPEARS AT EITHER LEVEL IN ANY RESIDENTIAL DISTRICT. THE CODE DOES DEFINE 'TOURIST HOME' in § 175-3 ('a private residence in which overnight sleeping accommodations are provided for overnight transient paying guests') and expressly excludes hotels, motels, automobile courts, bed-and-breakfasts, tourist homes, furnished rooming houses, dormitories, boarding homes and 'other accommodation used for transient occupancy' from the definitions of 'apartment' and 'apartment building' — so the drafters had the transient-lodging concept in mind and placed it nowhere in a residential district. THE WHOLE-CODE SWEEP WAS ALSO RUN AND IS MANDATORY IN THIS COUNTY: all 34 substantive chapters of the Village Code were enumerated from /WE0133 and there is no rental, registration, occupancy or property-maintenance chapter. CHAPTER 75 LICENSES AND PERMITS — flagged in the county handoff as the most likely home of a rental permit on the Gates Ch. 148 / Mendon Ch. 208 / Village of Pittsford Ch. 154 pattern — WAS OPENED AND IS NOT ONE: it is 613 characters covering Article I Billiard Rooms and Pool Rooms, Article II Circuses, Sideshows and Outdoor Exhibitions, and Article III Merry-Go-Rounds and Other Rides. That candidate is closed; do not re-check it. New York State's 2025 statewide short-term rental registry (Ch. 99 of the Laws of 2025) still obliges every host to register regardless of local law. Confirm with the Building Department at (585) 265-3770. Separate question from whether you can build the unit.
- Building dept(585) 265-3770
Sizing up a specific parcel in Webster?
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Building a full house instead?
A standard-finish house in Webster runs $204–268/sq ft, about $370k–480k at 1,800 sq ft . See what it costs to build a house in Webster.
ADU cost in nearby towns
All Monroe County towns: Rochester (City) · Brighton · Chili · Clarkson · Gates · Greece · Hamlin · Henrietta · Irondequoit · Mendon · Ogden · Parma · Penfield · Perinton · Pittsford · Riga · Rush · Sweden · Webster · Wheatland · Town/Village of East Rochester (Village) · Brockport (Village) · Churchville (Village) · Fairport (Village) · Hilton (Village) · Honeoye Falls (Village) · Pittsford (Village) · Scottsville (Village) · Spencerport (Village)
More on Webster: Can you build an ADU here? · Zoning for new construction · Monroe County build cost
ADU cost in Webster: common questions
How much does it cost to build an ADU in Webster, NY?
An 800 sq ft accessory dwelling unit in Village of Webster runs roughly $200k–260k at a standard finish, general-contractor margin included. A 400 sq ft studio runs about $130k–175k. Those are structure costs on an easy site and do not include the septic, water or electrical service work a second unit often triggers.
Why does an ADU cost more per square foot than a house in Webster?
Because a lot of a dwelling's cost is per dwelling, not per square foot. One kitchen, one bath group, one service panel and one heating plant cost about the same in an 800 sq ft cottage as in a 1,800 sq ft house, so on the smaller unit they get spread over less than half the floor area. That is why an ADU here prices at $249–327/sq ft against $204–268/sq ft for a full house, even though it is the same trades doing the same work.
Are ADUs allowed in Webster?
Village of Webster has 4 districts. All districts prohibit ADUs. Check the specific address with the free ADU checker or confirm with the building department at (585) 265-3770 before you spend money on design.
Can I rent an ADU in Webster short term?
Short-term rentals prohibited for Village of Webster. ADU rules and short-term-rental rules are set separately, so a unit you are allowed to build is not automatically one you are allowed to rent nightly. Confirm both before you underwrite the build on short-term-rental income.
ADU costs are modeled estimates in current 2026 dollars at the Monroe County regional index, general-contractor margin included, derived from Offsite's cost engine with a stated adjustment for the equipment a dwelling needs one of regardless of size. They are planning numbers for decision-support only - not a bid, quote, or guarantee, and not legal, architectural or engineering advice. They cover the structure and exclude septic expansion, utility service runs, site work beyond a flat and clear pad, and permit fees. ADU eligibility, size, owner-occupancy and permit conditions in the Village of Webster vary by district and often carry exceptions this page does not show; zoning last reviewed 2026-08-14; verify with the building department at (585) 265-3770 before relying on any answer. Sources: Offsite / Aldo cost engine (costEngine.js + constants.js); zoning dataset (municipalData.js).