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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.

A home addition joins a new structure to an existing one, so site, foundation, envelope and interior tie-ins belong in the first conversation. The extra square footage is only one part of the project. In Centerville, the first brief should also account for Montgomery County review and the property's existing conditions.
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.
Centerville says building approvals cover residential and commercial construction, including building, electric, plumbing, HVAC, gas and occupancy. Zoning permits are also required for many home-improvement projects and additions.
The city recommends submitting residential plans at least two weeks before the intended start and says the application is incomplete until the required materials and fees are submitted.
Local checkpoint source: City of Centerville Building Inspection. Verified September 20, 2026.
Planning in Centerville
An addition connects a new structure to an existing home and a real site, so feasibility comes before finish selections.
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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.
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.
Setbacks, lot coverage, easements and the location of utilities all limit where an addition can go and how large it can be. The local zoning authority has the final say, so it helps to check those limits before paying for detailed drawings.
Sometimes. Whether the existing system can serve the new space depends on its capacity and the duct layout, and larger additions often get separate equipment. It should be evaluated during planning, not after the framing is up.
Neither is automatically simpler. A second story avoids new footings but needs the existing walls and foundation to carry the extra load, plus a plan for the living space below. A ground-level addition needs new footings and a roof tie-in but leaves the rest of the house largely undisturbed.
The range follows the foundation and site work, structural connection, roof and exterior tie-ins, windows, utilities, HVAC, plumbing, drawings, approvals and finishes. A room addition, bump-out, second story and in-law suite carry different assumptions, so the scope needs to identify the type before a number is meaningful.
It may, depending on the property, setbacks, lot coverage, easements, footprint and local jurisdiction. Confirm the address-specific zoning and building path before detailed design or excavation, and make clear who prepares drawings, submits applications and schedules inspections.
The timeline includes feasibility, design, approvals, site work, foundation, framing, weather protection, utility tie-ins, inspections and interior finishes. The connection to the existing home and the approval path usually matter more than the square footage alone.
Centerville says building approvals cover residential and commercial construction, including building, electric, plumbing, HVAC, gas and occupancy. Zoning permits are also required for many home-improvement projects and additions. Check setbacks, lot coverage, easements, foundation conditions, roof and structural tie-ins, utility capacity and the local approval path. A home additions proposal in Centerville should identify who prepares drawings, submits applications and schedules inspections.
The agreement should identify the work, materials or allowances, exclusions, payment stages, schedule assumptions, permit responsibilities, cleanup and the process for changes. A single total without those details is difficult to compare or protect.
A change should be described in writing before the added work begins: what changed, why it changed, the price effect and the schedule effect. Concealed conditions and owner-requested changes are handled separately from the agreed scope.
For products that include a manufacturer warranty, keep the product name, model, registration instructions and applicable terms. The manufacturer sets that coverage. The contract should separately state any workmanship responsibility and how a problem is reported.
Walls, framing, wiring, plumbing, moisture and site conditions are not fully visible before demolition. The responsible next step is to document the condition, explain the options, update the cost or schedule in writing and get approval before proceeding with changed work.
Compare the scope line by line: demolition, structural work, rough-ins, finishes, allowances, permits, inspections, disposal, protection of occupied areas, cleanup, closeout and changes. The lowest headline number is not comparable if it leaves out different work.
The proposal should address access, dust control, floor and furniture protection, daily cleanup, temporary utilities, working hours and how damage is documented. Dayton Elite General Contractors is insured for the work it performs, and the project agreement should explain how any damage is reported and handled.