Dedicated second-story project references
Angi publishes a dedicated project range, a reported average, a unit range, a separate high-end unit threshold, a permit range, and a foundation-reinforcement starting point. These are individually scoped references rather than parts of a formula.
| Published reference | Value | What it measures |
|---|---|---|
| Second-story addition project rangeAngi · Cost Insights and article introduction | $100,000–$250,000 | Dedicated article range across size, design, rooms, and structural condition. |
| Reported second-story addition averageAngi · Article introduction | $175,000 | Publisher-reported average, not a Ramefor midpoint. |
| Second-story unit referenceAngi · Cost to Add a Second Story per Square Foot | $100–$300/sq ft | Broad unit reference; never multiplied by Ramefor. |
| High-end second-story unit thresholdAngi · Cost to Add a Second Story per Square Foot | $500 (up to)/sq ft | Separate high-end threshold, not every project's upper endpoint. |
| Second-story building permit referenceAngi · Cost Insights | $1,200–$2,000 | National planning reference; local requirements control. |
| Foundation reinforcement starting pointAngi · Cost Insights | $5,000 (starting at) | Starting point, never an automatic allowance. |
The dedicated table covers 800–1,100 square feet
Each row publishes an average cost range and a maximum. Ramefor preserves those as different semantic values. None feeds the home-addition calculator, and no result is derived by multiplying the unit reference.
| Published reference | Value | What it measures |
|---|---|---|
| 800 sq ft average cost rangeAngi · Cost to Add a Second Story per Square Foot > size table | $80,000–$240,000 | Published 800 sq ft average-range cell. |
| 800 sq ft maximumAngi · Cost to Add a Second Story per Square Foot > size table | $400,000 | Published 800 sq ft maximum, not an average. |
| 900 sq ft average cost rangeAngi · Cost to Add a Second Story per Square Foot > size table | $90,000–$270,000 | Published 900 sq ft average-range cell. |
| 900 sq ft maximumAngi · Cost to Add a Second Story per Square Foot > size table | $450,000 | Published 900 sq ft maximum, not an average. |
| 1,000 sq ft average cost rangeAngi · Cost to Add a Second Story per Square Foot > size table | $100,000–$300,000 | Published 1,000 sq ft average-range cell. |
| 1,000 sq ft maximumAngi · Cost to Add a Second Story per Square Foot > size table | $500,000 | Published 1,000 sq ft maximum, not an average. |
| 1,100 sq ft average cost rangeAngi · Cost to Add a Second Story per Square Foot > size table | $110,000–$330,000 | Published 1,100 sq ft average-range cell. |
| 1,100 sq ft maximumAngi · Cost to Add a Second Story per Square Foot > size table | $550,000 | Published 1,100 sq ft maximum, not an average. |
Establish structural feasibility before selecting finishes
This Old House's current process guide emphasizes foundation and structural capacity, soil and loads, zoning, permits, roof removal, framing, stairs, utilities, weather protection, and integration with the existing floor. It attributes its cost figures to older Angi data, so Ramefor uses the page for process only.
- Ask a structural professional to review available plans, footings, foundation walls, slabs, framing, load paths, soil assumptions, and evidence of cracking or movement.
- Confirm height, floor-area, setback, massing, fire-safety, egress, stair, and other zoning or building constraints with the relevant authority.
- Define full versus partial addition, roof removal and reconstruction, temporary shoring, dry-in milestones, and responsibility for weather damage.
- Coordinate staircase position, headroom, circulation, electrical service, plumbing pressure and drainage, water heating, HVAC capacity, and penetrations through the existing floor.
Plan occupancy, protection, sequence, and closeout
- Decide whether occupants can remain safely in the home and define temporary housing, utility shutdowns, dust separation, exits, security, and daily cleanup.
- Require a written schedule for design, engineering, approvals, roof opening, framing, dry-in, rough trades, inspections, insulation, finishes, and punch-list work.
- Protect occupied rooms, furniture, HVAC returns, floors, ceilings, and the existing envelope while structure and roof are open.
- Compare quotes for the same drawings, specifications, allowances, exclusions, temporary works, permits, inspections, change-order procedure, and closeout documents.
Sources, review dates, and limitations
Every dollar figure on this page comes from a registered source below. The figures remain separate because their project definitions and research methods differ.
Angi
How Much Does It Cost to Add a Second Story to Your Home? [2026 Data]
- Source published/updated
- Ramefor verified
How we use it: Ramefor uses this dedicated Angi page for second-story pricing context only; none of its rows feed the home-addition calculator.
Scope and limitations
- This dedicated dataset covers 800–1,100-square-foot rows and must not be blended with the 60–400-square-foot Second Story Build cells in Angi's general home-addition table.
- Full, partial, dormer, bonus-room, and structural scopes are not interchangeable.
- The article gives a broad three-to-twelve-month construction statement, which remains non-monetary editorial context.
This Old House
How To Add a Second Floor To Your Existing House
- Source published/updated
- Ramefor verified
How we use it: Process and scope source only. Its monetary figures are excluded because the page attributes them to 2024 Angi data and its rendered table contains a labeling inconsistency.
Scope and limitations
- Ramefor uses this source for structural assessment, foundation and soil capacity, zoning, permits, roof removal, framing, utilities, weather protection, sequencing, and temporary-living planning.
- The article explicitly attributes its cost figures to 2024 Angi data, so Ramefor does not register them as an independent 2026 pricing dataset.
- Its rendered cost table repeats the 1,000-square-foot label on the final row, reinforcing the decision not to use that table for pricing.
Related home additions resources
An orientation, not an estimate
These national references do not account for your location, taxes, existing conditions, product selections, contractor availability, or final scope. Get itemized local quotes before making a financial decision.