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Written scope and price
Once the scope and selections are agreed in writing, the agreed work is not repriced without a documented change. Owner-requested changes and concealed conditions are explained before changed work proceeds.

Dayton, OH and the Miami Valley
We build home additions in Troy, OH, including room and second-story additions that connect to your existing home, roof and utilities.
Planning guide
Choose the closest project scope to see an early planning range. This is not a quote.
Build the project scope
Select the choices closest to the work. Each one changes the planning range and the breakdown below.
Typical planning range. Not a quote.
$56,000–$110,000
Planning breakdown
Representative midpoint by scope component
How to read the range
A property review turns this range into a project-specific scope. The written scope, selections, allowances and exclusions are what make the final number comparable.
If an owner change or concealed condition affects cost or timing, it should be described in writing and approved before changed work proceeds.
Project planner
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Short answer. Resolve footprint, access, easements and utility locations on the site plan before finalizing foundation and tie-in pricing; submit the complete package before assigning a construction start.
| Median year built | 1972 |
|---|---|
| Homes built before 1980 | 61% |
| Homes built in 2000 or later | 22% |
| Median home value | $217,400 |
| Owner-occupied homes | 66% |
72% of Troy's housing units are single-family detached homes, and the median home is valued at $217,400. Its share of detached homes is the 6th lowest of the 12 communities we serve. Older streets and newer subdivisions here follow different lot patterns, so the first question for an addition is how much room the lot allows. An older house may have a stone or block foundation and mixed framing at the connection point. A newer one usually has engineered framing and a simpler connection, but may be limited by easements and setbacks.
Housing figures: U.S. Census Bureau, American Community Survey 2020-2024 5-year estimates, retrieved October 25, 2026. Statements about what homes of an age typically contain are general and must be confirmed on site.
Sources: Miami County Building Regulations; Miami County required inspections list; Miami County residential plan review requirements; Miami County areas of jurisdiction; Troy Planning and Zoning. Read October 25, 2026. Fees and forms change, so confirm them for your address before work starts.
Troy's addition checklist calls for a scaled site plan with project location and dimensions, and supporting items such as utilities and easements.
Health department approval is required when an addition has new plumbing, according to Miami County, and final plumbing must be approved before the final structure inspection.
Plumbing approval source: Miami County permit guidance (plumbing approvals through Public Health). Checked October 25, 2026.
Local checkpoint source: City of Troy Planning and Zoning. Verified October 8, 2026.
The scope should cover setbacks, lot conditions, foundation approach, structural tie-in, roof and drainage, insulation, windows, utilities, HVAC capacity, interior transitions and protection of the occupied portion of the home. A sketch is useful, but the written scope must name the assumptions behind it.
Additions need a sequence that protects the existing house while the new space is exposed to weather. Confirm drawings, zoning questions, permit responsibility, utility changes, inspection stages and the temporary access path before demolition or excavation is placed on the calendar.
Planning in Troy
An addition connects a new structure to an existing home and a real site, so feasibility comes before finish selections.
01
Once the scope and selections are agreed in writing, the agreed work is not repriced without a documented change. Owner-requested changes and concealed conditions are explained before changed work proceeds.
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When a product includes a manufacturer warranty, keep its product information, registration details and terms. Manufacturer coverage belongs to the product; any workmanship responsibility should be stated separately in the project agreement.
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We protect access areas, document changes and carry insurance for the work we perform. If property is damaged, the issue is documented and handled under the project agreement and applicable coverage.
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At handover, keep the final scope, approved changes, inspection records, product information, care instructions and the right contact for any follow-up.
Planning ranges are starting points, not quotes. Final scope, selections, property conditions, approvals and written assumptions control the real project price.
Budgeting before you call? Read the Home Addition Cost in Dayton, OH guide for typical planning ranges and what moves the price.
Planning guide
Choose the closest project scope to see an early planning range. This is not a quote.
Build the project scope
Select the choices closest to the work. Each one changes the planning range and the breakdown below.
Typical planning range. Not a quote.
$56,000–$110,000
Planning breakdown
Representative midpoint by scope component
How to read the range
A property review turns this range into a project-specific scope. The written scope, selections, allowances and exclusions are what make the final number comparable.
If an owner change or concealed condition affects cost or timing, it should be described in writing and approved before changed work proceeds.
The estimate explains what is included, what is excluded and which decisions need to be made before work starts. Agreed work is not repriced without a documented change.
When products include manufacturer warranties, product information and applicable terms stay with the project record. Workmanship responsibility belongs in the written agreement.
When a project needs drawings, permits or inspections, we identify the jurisdiction and likely sequence early so the schedule is built around real constraints.
Troy's checklist calls for a scaled plan with the project location and dimensions, along with items such as parking, utilities and easements. Confirm the current checklist for the parcel before the addition is priced as final.
Yes. 72% of Troy's housing units are single-family detached homes, and the median home is valued at $217,400. Its share of detached homes is the 6th lowest of the 12 communities we serve. Identify the lot pattern and the foundation type at the connection point before design.
The city's development guidance says permanent additions typically need a zoning permit. Check the parcel, proposed footprint and current application requirements with Troy Planning and Zoning.