Home addition cost in Charleston, SC
Local estimate from BLS wage data and BEA price levels. Reviewed Nov 4, 2026.
- Typical range (300 sq ft)
- $33,600 – $68,200
- Per sq ft
- $110 – $220
- before permit
- Versus US midpoint
- −12%
- US $57,500
- Rank of 300 metros
- #215
- 1 = most expensive
A home addition in Charleston, SC usually costs $33,600 to $68,200 for 300 sq ft. That works out to about $110 to $220 per sq ft before permits. Compared with the national midpoint that is $6,650 less. Carpenters earn a median of $24.22 an hour in the Charleston area, 17% below the US median of $29.12.
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Estimated cost for 300 sq ft in Charleston, SC, standard level
$44,000 to $57,800
About $143 to $187 per sq ft before permits. Labor is about 63% of the bill.
| Part | Low | High |
|---|---|---|
| Materials | $15,000 | $19,700 |
| Labor | $28,000 | $36,600 |
| Permits and fees | $960 | $1,550 |
| Total | $44,000 | $57,800 |
Cost breakdown for 300 sq ft in Charleston, SC
| Part of the job | Low | Midpoint | High | Share |
|---|---|---|---|---|
| Materials | $11,600 | $17,300 | $23,100 | 34% |
| Labor | $21,500 | $32,300 | $43,000 | 63% |
| Permits and fees | $500 | $1,250 | $2,000 | 2% |
| Total | $33,600 | $50,900 | $68,200 | 100% |
Why Charleston prices look the way they do
We price the labor side from BLS wage data for 6 trades: carpenters at 50%, cement masons and concrete finishers at 10%, electricians at 10%, plumbers, pipefitters and steamfitters at 10%, drywall and ceiling tile installers at 10%, roofers at 10%. Weighted together, Charleston wages are 0.84 times the national level. Labor makes up about 63% of the midpoint estimate (67% at national prices).
Materials are scaled with BEA's regional price parity for goods. Charleston is at 96.3 against 100 for the US, so a materials line of $18,000 nationally becomes $17,300 here (midpoint, 300 sq ft). Permits follow the all-items index of 101.0: $500 to $2,000.
Why two Charleston quotes can differ
Foundation
A foundation, framing, roofing and matching exterior finishes all have to be built before the interior work starts.
Type of addition
A new room is $125-$250 per sq ft; a bump-out $85-$200; an attic conversion $50-$150; a garage conversion $50-$200 (HomeGuide).
Plumbing and fixtures
Adding a bathroom or kitchen drives the price up the most.
Charleston: what basic, standard and premium work costs
The cited range is split into basic, standard and premium bands, then scaled to Charleston. Bands overlap, because plenty of standard jobs cost as much as a light premium one. Sizes run from bump-out (100 sq ft) to large suite (600 sq ft).
Basic
$33,600 to $47,400
Bump-out or simple room without plumbing
Standard
$44,000 to $57,800
Standard room addition with HVAC and electrical
Premium
$54,300 to $68,200
Large addition with bath or kitchen and a new foundation
| Size | Basic | Standard | Premium |
|---|---|---|---|
| bump-out (100 sq ft) | $11,500 – $16,500 | $15,300 – $20,300 | $19,100 – $24,100 |
| 20x20 room (400 sq ft) | $44,600 – $62,800 | $58,300 – $76,500 | $72,000 – $90,200 |
| large suite (600 sq ft) | $66,700 – $93,700 | $86,900 – $114,000 | $107,000 – $134,500 |
Charleston weather and the home addition calendar
Climate numbers on this page come from NOAA's 1991-2020 U.S. Climate Normals at the nearest suitable station, Charleston City (5 miles from the city center). They are 30-year averages, so any one year can run hotter, colder or wetter.
Weather is not a serious constraint for digging, grading and setting material in the ground in Charleston: no month in the averages is cold enough (an average overnight low at or below freezing (32°F)) or hot enough (an average daytime high of 90°F or more) to rule it out, so the workable window is all year.
Charleston gets about 44 inches of precipitation in a normal year. The wettest months are July, August and September (6.1 inches in August). The station averages about 25 days a year at 90°F or above.
We do not adjust the estimate by month, because we have no reliable published data on seasonal pricing. It is still worth asking contractors whether an off-peak start date changes their bid.
| Month | Avg high °F | Avg low °F | Precip (in) | For this job |
|---|---|---|---|---|
| Jan | 58 | 44 | 2.6 | Workable |
| Feb | 60 | 46 | 2.6 | Workable |
| Mar | 66 | 52 | 3.0 | Workable |
| Apr | 72 | 60 | 3.0 | Workable |
| May | 79 | 68 | 2.6 | Workable |
| Jun | 84 | 74 | 4.8 | Workable |
| Jul | 88 | 77 | 5.1 | Workable |
| Aug | 86 | 77 | 6.1 | Workable |
| Sep | 83 | 73 | 5.3 | Workable |
| Oct | 76 | 63 | 4.1 | Workable |
| Nov | 67 | 53 | 2.3 | Workable |
| Dec | 61 | 47 | 2.9 | Workable |
What local crews earn in Charleston
The labor line is built from BLS wage data, one trade at a time. This job draws on 6 trades. We compare each trade's local median with the US median, weight the ratios by how much of the job each trade does, and apply the blend to the national labor cost. For Charleston the blend is 0.84.
Carpenters (47-2031), 50% of the weighting: a median of $24.22 an hour, 17% below the US median of $29.12. The middle half of them earn between $21.37 and $29.52 an hour. About 1,240 work in the metro. That is 31.5 per 10,000 jobs, compared with 43.1 nationally, so expect fewer local crews to bid.
Cement masons and concrete finishers (47-2051), 10% of the weighting: a median of $25.27 an hour, 8% below the US median of $27.41. The middle half of them earn between $22.52 and $30.36 an hour. About 300 work in the metro. That is 7.6 per 10,000 jobs, compared with 13.3 nationally, so expect fewer local crews to bid.
For electricians (47-2111, weighted 10%) the local median is $28.37 an hour, which is 7% below the national $30.38. The middle half of them earn between $23.54 and $31.81 an hour. BLS counts 1,480 of them working in the area, 37.5 for every 10,000 jobs (US: 48.7), so the local bench is thinner than average.
Plumbers, pipefitters and steamfitters (47-2152), 10% of the weighting: a median of $27.58 an hour, 10% below the US median of $30.67. The middle half of them earn between $23.50 and $31.15 an hour. About 960 work in the metro. That is 24.4 per 10,000 jobs, compared with 30.0 nationally, so expect fewer local crews to bid.
For drywall and ceiling tile installers (47-2081, weighted 10%) the local median is $18.59 an hour, which is 34% below the national $28.33. The middle half of them earn between $18.36 and $23.51 an hour. BLS counts 70 of them working in the area, 1.8 for every 10,000 jobs (US: 5.3), so the local bench is thinner than average.
Roofers (47-2181), 10% of the weighting: a median of $23.09 an hour, 13% below the US median of $26.65. The middle half of them earn between $18.81 and $29.46 an hour. About 110 work in the metro. That is 2.8 per 10,000 jobs, compared with 8.7 nationally, so expect fewer local crews to bid.
A quick sensitivity check: moving the lead trade (carpenters) from the median to the 75th percentile wage adds about $3,500 to the midpoint estimate; the 25th percentile takes off about $1,850. That is a swing of roughly 3.7% to 6.8% of the total, which is useful for judging whether a bid reflects wages or something else, such as scope or margin.
Charleston-North Charleston has 394,170 jobs in total (BLS, May 2025), ranking 66th by size among the 300 metros on this site.
| Trade | Weight | 25th pct | Median | 75th pct | US median | Ratio | Level used |
|---|---|---|---|---|---|---|---|
| Carpenters (47-2031) | 50% | $21.37 | $24.22 | $29.52 | $29.12 | 0.83 | metro |
| Cement masons and concrete finishers (47-2051) | 10% | $22.52 | $25.27 | $30.36 | $27.41 | 0.92 | metro |
| Electricians (47-2111) | 10% | $23.54 | $28.37 | $31.81 | $30.38 | 0.93 | metro |
| Plumbers, pipefitters and steamfitters (47-2152) | 10% | $23.50 | $27.58 | $31.15 | $30.67 | 0.90 | metro |
| Drywall and ceiling tile installers (47-2081) | 10% | $18.36 | $18.59 | $23.51 | $28.33 | 0.66 | metro |
| Roofers (47-2181) | 10% | $18.81 | $23.09 | $29.46 | $26.65 | 0.87 | metro |
| Blended | 100% | 0.84 | |||||
Charleston against nearby metros and the rest of South Carolina
Contractors rarely work more than an hour or two from home, so the neighboring metros set a rough ceiling and floor for your quotes. Midpoints for 300 sq ft range from $48,800 to $50,900 across Charleston and its five closest metros.
| Area | Range | Midpoint | vs. here |
|---|---|---|---|
| Charleston, SCthis page | $33,600 – $68,200 | $50,900 | |
| Hilton Head, SC65 miles | $33,300 – $67,600 | $50,500 | −1% |
| Florence, SC80 miles | $33,100 – $67,000 | $50,100 | −2% |
| Myrtle Beach, SC85 miles | $32,200 – $65,400 | $48,800 | −4% |
| Columbia, SC95 miles | $32,900 – $66,800 | $49,900 | −2% |
| Savannah, GA95 miles | $33,100 – $67,100 | $50,100 | −2% |
| South Carolina (statewide) | $33,500 – $67,900 | $50,700 | level |
| United States | $38,000 – $77,000 | $57,500 | +13% |
Out of the 300 metros we cover, Charleston ranks #215 for the cost of this job (#1 is the most expensive). Statewide, Charleston is 0% above the South Carolina figure.
Elsewhere in South Carolina
| Metro | Size | Range | Midpoint | vs. here |
|---|---|---|---|---|
| Greenville, SC | 434,900 jobs | $33,400 – $67,700 | $50,600 | −1% |
| Columbia, SC | 394,200 jobs | $32,900 – $66,800 | $49,900 | −2% |
| Spartanburg, SC | 165,150 jobs | $33,600 – $68,100 | $50,900 | level |
| Myrtle Beach, SC | 146,260 jobs | $32,200 – $65,400 | $48,800 | −4% |
| Florence, SC | 89,060 jobs | $33,100 – $67,000 | $50,100 | −2% |
| Hilton Head, SC | 81,920 jobs | $33,300 – $67,600 | $50,500 | −1% |
Metros of a similar size
Big cities and small ones price differently, so here is Charleston against the 4 metros with the closest total employment.
| Metro | Size | Range | Midpoint | vs. here |
|---|---|---|---|---|
| Columbia, SC | 394,200 jobs | $32,900 – $66,800 | $49,900 | −2% |
| Boise, ID | 391,790 jobs | $34,700 – $70,400 | $52,500 | +3% |
| Des Moines, IA | 404,130 jobs | $37,300 – $75,400 | $56,300 | +11% |
| Tucson, AZ | 389,630 jobs | $33,800 – $68,600 | $51,200 | +1% |
Planning more than one job in Charleston?
Jobs that often go together with home addition are priced below at their usual sizes, using the same Charleston wage and price inputs. Compared with national midpoints, kitchen remodel comes out highest (−6%) and bathroom remodel lowest (−10%); the gap comes from the trades each job uses.
| Project | Size | Range | vs. US |
|---|---|---|---|
| Kitchen remodel | 120 sq ft | $17,400 – $29,700 | −6% |
| Bathroom remodel | 45 sq ft | $4,250 – $21,000 | −10% |
| Detached garage | 576 sq ft | $26,700 – $53,500 | −8% |
| Roof replacement | 2,000 sq ft of roof | $5,500 – $11,400 | −9% |
Get 3 local quotes
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Home addition in Charleston: your questions
+How much does it cost to build a home addition in Charleston?
For 300 sq ft, expect $33,600 to $68,200 in the Charleston area. A standard-spec job lands at $44,000 to $57,800. Small jobs usually cost more per sq ft and large ones less.
+What is the price per sq ft for home addition in Charleston?
About $110 to $220 per sq ft for materials and labor, plus $500 to $2,000 for the permit if one is needed. The US range is $125 to $250.
+Is home addition cheaper in Charleston or Hilton Head?
Hilton Head is 65 miles away. The midpoint for 300 sq ft there is $50,500, which is 1% less than Charleston ($50,900). Wage and materials indexes both feed that gap.
+How much of the bill is labor in Charleston?
About 63% at the midpoint, or $32,300 out of $50,900. Materials are 34% and permits 2%. Nationally, labor is 67%.
+What would 20x20 room (400 sq ft) cost in Charleston?
$44,600 to $90,200. Pick a different size in the estimator above to get your own number.
+Does home addition need a permit in Charleston?
Often, but rules are set by your city or county building office, so call before you hire. Budget $500 to $2,000 for fees in the Charleston area (our national range of $500 to $2,000 scaled by the local price level).
+Is Charleston expensive for home addition compared with the rest of South Carolina?
Charleston is 0% above the South Carolina statewide estimate ($50,700 at the midpoint). We cover 7 metros in South Carolina; see the state page to compare them.
+What do carpenters earn in Charleston?
The BLS median is $24.22 an hour in the Charleston area, compared with $29.12 nationally. The 25th to 75th percentile range is $21.37 to $29.52.
+What do basic and premium home addition work cost in Charleston?
For 300 sq ft, basic work runs $33,600 to $47,400 and premium work $54,300 to $68,200. Basic means: bump-out or simple room without plumbing. Premium means: large addition with bath or kitchen and a new foundation.
+Is there a bad season to build a home addition in Charleston?
Not from a temperature point of view. NOAA's 1991-2020 normals show no month with a freezing-level overnight low or a 90°F-plus average high, so timing is mostly about contractor availability and rain.
Home addition near Charleston
Where these numbers come from
Base prices are national ranges from the sources below. We scale labor by local BLS wages, materials by BEA goods prices and permits by the BEA all-items price level. Full method on the methodology page.
- HomeGuide: How Much Does a Home Addition Cost? (2026) (accessed November 4, 2026)
- Cost to Renovate: Renovation Labor Report 2026: Where the Money Goes (accessed November 4, 2026)
- HomeGuide: 2026 Building Permit Costs | Fees & Cost Calculator (accessed November 4, 2026)
- BLS Occupational Employment and Wage Statistics, May 2025
- BEA Regional Price Parities, 2024
- NOAA NCEI U.S. Climate Normals, 1991-2020
Note on derived figures: Materials = 32% of the installed price, from Cost to Renovate's mid-range 'Structural' category split (56% labor, 32% materials, 11% permits and design). It is a category average rather than an addition-specific figure.