Home addition cost in Knoxville, TN
Local estimate from BLS wage data and BEA price levels. Reviewed Nov 4, 2026.
- Typical range (300 sq ft)
- $33,600 – $68,100
- Per sq ft
- $110 – $221
- before permit
- Versus US midpoint
- −12%
- US $57,500
- Rank of 300 metros
- #217
- 1 = most expensive
If you want to build a home addition in Knoxville, plan on $33,600 to $68,100 for 300 sq ft, all in. Per sq ft, that is $110 to $221 for materials and labor, with the permit on top. The local midpoint runs 12% lower than the national one. Carpenters earn a median of $24.23 an hour in the Knoxville area, 17% below the US median of $29.12.
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Estimated cost for 300 sq ft in Knoxville, TN, standard level
$43,900 to $57,700
About $143 to $188 per sq ft before permits. Labor is about 64% of the bill.
| Part | Low | High |
|---|---|---|
| Materials | $15,000 | $19,600 |
| Labor | $28,000 | $36,600 |
| Permits and fees | $880 | $1,450 |
| Total | $43,900 | $57,700 |
Cost breakdown for 300 sq ft in Knoxville, TN
| Part of the job | Low | Midpoint | High | Share |
|---|---|---|---|---|
| Materials | $11,500 | $17,300 | $23,100 | 34% |
| Labor | $21,600 | $32,300 | $43,100 | 64% |
| Permits and fees | $460 | $1,150 | $1,850 | 2% |
| Total | $33,600 | $50,800 | $68,100 | 100% |
Why Knoxville prices look the way they do
The wage side of the estimate leans on carpenters, who do 50% of the hours on a typical job. Their local median is $24.23 an hour. Add the other trades involved and the blended wage index for Knoxville is 0.85 (US = 1.00), which puts labor at 64% of the total.
On the materials line, the BEA goods price index for the Knoxville metro is 96.2 (US = 100). The midpoint materials bill for 300 sq ft comes to $17,300, compared with $18,000 at national prices. Permit and inspection fees are scaled by the broader index (92.6) and land at $460 to $1,850.
Data note: 10% of the labor weighting for this project uses a statewide median because BLS has no published metro figure for that trade in Knoxville. The wage table below marks each row.
Climate in Knoxville: timing your home addition job
We use NOAA's 1991-2020 climate normals for Knoxville Mcghee Tyson Ap (10 miles from the city center). These are 30-year monthly averages, not forecasts.
February through December is the stretch where digging, grading and setting material in the ground runs into the fewest weather problems in Knoxville (11 of 12 months). January has an average overnight low at or below freezing (32°F).
In January the average low is at or below freezing, which means frozen ground and slower digging, compaction and sod or stone placement. NOAA counts about 67 days a year with a low at or below 32°F at this station.
Knoxville gets about 52 inches of precipitation in a normal year, including roughly 5 inches of snow. The wettest months are March, July and December (5.3 inches in July). Inside the workable window, September and October are the driest, at 3.5 and 2.8 inches. The station averages about 37 days a year at 90°F or above.
Does the season change the price? Probably, but we do not have a sourced seasonal price curve, so the estimator shows a year-round figure and does not adjust by month. When you collect quotes, ask whether scheduling in a slower month gets a better rate.
| Month | Avg high °F | Avg low °F | Precip (in) | For this job |
|---|---|---|---|---|
| Jan | 48 | 30 | 4.8 | Cold |
| Feb | 53 | 33 | 4.8 | Workable |
| Mar | 61 | 40 | 4.9 | Workable |
| Apr | 71 | 48 | 4.7 | Workable |
| May | 79 | 57 | 4.1 | Workable |
| Jun | 86 | 65 | 4.2 | Workable |
| Jul | 88 | 69 | 5.3 | Workable |
| Aug | 88 | 68 | 3.6 | Workable |
| Sep | 83 | 61 | 3.5 | Workable |
| Oct | 72 | 49 | 2.8 | Workable |
| Nov | 60 | 38 | 4.2 | Workable |
| Dec | 51 | 33 | 5.0 | Workable |
Cost by quality level and size in Knoxville
Three bands are cut from the same cited range and localized for Knoxville wages and prices. They overlap on purpose: a good standard job and a modest premium job can cost the same. The grid below prices the same bands at 3 common sizes.
Basic
$33,600 to $47,400
Bump-out or simple room without plumbing
Standard
$43,900 to $57,700
Standard room addition with HVAC and electrical
Premium
$54,300 to $68,100
Large addition with bath or kitchen and a new foundation
| Size | Basic | Standard | Premium |
|---|---|---|---|
| bump-out (100 sq ft) | $11,500 – $16,500 | $15,200 – $20,200 | $18,900 – $23,900 |
| 20x20 room (400 sq ft) | $44,600 – $62,800 | $58,300 – $76,500 | $71,900 – $90,100 |
| large suite (600 sq ft) | $66,700 – $93,700 | $86,900 – $114,000 | $107,000 – $134,500 |
Why two Knoxville quotes can differ
Permits
Construction permits run $500-$2,000, or $5-$21 per $1,000 of project cost (HomeGuide).
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).
Knoxville labor market for home addition
Wages are the part of this estimate that changes most from town to town. 6 trades carry the job here, and each is compared with its US median. The weighted result for Knoxville is 0.85 times the national level.
For carpenters (47-2031, weighted 50%) the local median is $24.23 an hour, which is 17% below the national $29.12. The middle half of them earn between $22.11 and $28.56 an hour. BLS counts 1,280 of them working in the area, 30.1 for every 10,000 jobs (US: 43.1), so the local bench is thinner than average.
For cement masons and concrete finishers (47-2051, weighted 10%) the local median is $22.10 an hour, which is 19% below the national $27.41. The middle half of them earn between $20.71 and $23.82 an hour. BLS counts 550 of them working in the area, 13.0 for every 10,000 jobs (US: 13.3), so the local bench is about average.
Electricians (47-2111), 10% of the weighting: a median of $28.19 an hour, 7% below the US median of $30.38. The middle half of them earn between $22.79 and $34.73 an hour. About 2,170 work in the metro. That is 51.1 per 10,000 jobs, compared with 48.7 nationally, so the supply of crews looks typical.
For plumbers, pipefitters and steamfitters (47-2152, weighted 10%) the local median is $28.78 an hour, which is 6% below the national $30.67. The middle half of them earn between $22.69 and $35.32 an hour. BLS counts 1,700 of them working in the area, 40.0 for every 10,000 jobs (US: 30.0), so the local bench is deeper than average.
Drywall and ceiling tile installers (47-2081) carry 10% of the labor weighting. BLS does not publish this trade for the Knoxville metro, so we used the Tennessee statewide median: $22.84 an hour against $28.33 for the US. The middle half of them earn between $18.98 and $27.18 an hour.
For roofers (47-2181, weighted 10%) the local median is $21.65 an hour, which is 19% below the national $26.65. The middle half of them earn between $17.89 and $22.80 an hour. BLS counts 440 of them working in the area, 10.4 for every 10,000 jobs (US: 8.7), so the local bench is deeper than average.
Quotes come from real crews, not medians. If the carpenters on your job are paid at the 75th percentile ($28.56 an hour) instead of the median, the labor line grows by about $2,850. At the 25th percentile ($22.11) it shrinks by about $1,400. The total moves by 5.6% or 2.7%, so wages alone rarely explain a quote that is far outside our range.
For context on the local economy, BLS counts 424,600 jobs in the Knoxville area. That makes it the 59th largest of the 300 metros we cover, with 0.27% of US employment.
| Trade | Weight | 25th pct | Median | 75th pct | US median | Ratio | Level used |
|---|---|---|---|---|---|---|---|
| Carpenters (47-2031) | 50% | $22.11 | $24.23 | $28.56 | $29.12 | 0.83 | metro |
| Cement masons and concrete finishers (47-2051) | 10% | $20.71 | $22.10 | $23.82 | $27.41 | 0.81 | metro |
| Electricians (47-2111) | 10% | $22.79 | $28.19 | $34.73 | $30.38 | 0.93 | metro |
| Plumbers, pipefitters and steamfitters (47-2152) | 10% | $22.69 | $28.78 | $35.32 | $30.67 | 0.94 | metro |
| Drywall and ceiling tile installers (47-2081) | 10% | $18.98 | $22.84 | $27.18 | $28.33 | 0.81 | state |
| Roofers (47-2181) | 10% | $17.89 | $21.65 | $22.80 | $26.65 | 0.81 | metro |
| Blended | 100% | 0.85 | |||||
Related projects, priced for Knoxville
Because every project leans on different trades, Knoxville's wage level does not move all prices equally. Against the US midpoint, kitchen remodel runs −6% and roof replacement −12%.
| Project | Size | Range | vs. US |
|---|---|---|---|
| Kitchen remodel | 120 sq ft | $17,400 – $29,600 | −6% |
| Bathroom remodel | 45 sq ft | $4,250 – $21,000 | −10% |
| Detached garage | 576 sq ft | $26,500 – $53,100 | −9% |
| Roof replacement | 2,000 sq ft of roof | $5,300 – $11,100 | −12% |
Is Knoxville cheap or dear? The local comparison
Of the five closest metros, 3 are cheaper than Knoxville. Dalton is the lowest at about $48,400 (midpoint, 300 sq ft), 95 miles away.
| Area | Range | Midpoint | vs. here |
|---|---|---|---|
| Knoxville, TNthis page | $33,600 – $68,100 | $50,800 | |
| Asheville, NC95 miles | $33,700 – $68,400 | $51,100 | +1% |
| Dalton, GA95 miles | $31,900 – $64,800 | $48,400 | −5% |
| Chattanooga, TN95 miles | $34,000 – $68,900 | $51,500 | +1% |
| Johnson City, TN100 miles | $32,400 – $65,700 | $49,100 | −3% |
| Kingsport, TN100 miles | $32,700 – $66,200 | $49,400 | −3% |
| Tennessee (statewide) | $33,800 – $68,600 | $51,200 | +1% |
| United States | $38,000 – $77,000 | $57,500 | +13% |
Across 300 US metros, Knoxville comes in at #217 from the top. The priciest is Honolulu, HI at $79,600; the cheapest is Brownsville, TX at $44,300 (midpoints, 300 sq ft). Statewide, Knoxville is 1% below the Tennessee figure.
Other Tennessee metros
| Metro | Size | Range | Midpoint | vs. here |
|---|---|---|---|---|
| Nashville, TN | 1,099,300 jobs | $35,300 – $71,600 | $53,500 | +5% |
| Memphis, TN | 611,670 jobs | $33,900 – $68,700 | $51,300 | +1% |
| Chattanooga, TN | 268,750 jobs | $34,000 – $68,900 | $51,500 | +1% |
| Kingsport, TN | 119,560 jobs | $32,700 – $66,200 | $49,400 | −3% |
| Clarksville, TN | 103,220 jobs | $33,000 – $66,900 | $50,000 | −2% |
| Jackson, TN | 84,530 jobs | $32,700 – $66,300 | $49,500 | −3% |
Cities with a workforce like Knoxville's
Big cities and small ones price differently, so here is Knoxville against the 4 metros with the closest total employment.
| Metro | Size | Range | Midpoint | vs. here |
|---|---|---|---|---|
| Greenville, SC | 434,900 jobs | $33,400 – $67,700 | $50,600 | level |
| Baton Rouge, LA | 409,690 jobs | $36,100 – $73,100 | $54,600 | +7% |
| New Orleans, LA | 445,550 jobs | $33,800 – $68,500 | $51,100 | +1% |
| Madison, WI | 408,070 jobs | $40,200 – $81,300 | $60,700 | +20% |
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Home addition in Knoxville: your questions
+How much does it cost to build a home addition in Knoxville?
For 300 sq ft, expect $33,600 to $68,100 in the Knoxville area. A standard-spec job lands at $43,900 to $57,700. Small jobs usually cost more per sq ft and large ones less.
+What is the price per sq ft for home addition in Knoxville?
About $110 to $221 per sq ft for materials and labor, plus $460 to $1,850 for the permit if one is needed. The US range is $125 to $250.
+Is home addition cheaper in Knoxville or Asheville?
Asheville is 95 miles away. The midpoint for 300 sq ft there is $51,100, which is 1% more than Knoxville ($50,800). Wage and materials indexes both feed that gap.
+How much of the bill is labor in Knoxville?
About 64% at the midpoint, or $32,300 out of $50,800. Materials are 34% and permits 2%. Nationally, labor is 67%.
+What would 20x20 room (400 sq ft) cost in Knoxville?
$44,600 to $90,100. Pick a different size in the estimator above to get your own number.
+Does home addition need a permit in Knoxville?
Often, but rules are set by your city or county building office, so call before you hire. Budget $460 to $1,850 for fees in the Knoxville area (our national range of $500 to $2,000 scaled by the local price level).
+Is Knoxville expensive for home addition compared with the rest of Tennessee?
Knoxville is 1% below the Tennessee statewide estimate ($51,200 at the midpoint). We cover 8 metros in Tennessee; see the state page to compare them.
+What do carpenters earn in Knoxville?
The BLS median is $24.23 an hour in the Knoxville area, compared with $29.12 nationally. The 25th to 75th percentile range is $22.11 to $28.56.
+What do basic and premium home addition work cost in Knoxville?
For 300 sq ft, basic work runs $33,600 to $47,400 and premium work $54,300 to $68,100. Basic means: bump-out or simple room without plumbing. Premium means: large addition with bath or kitchen and a new foundation.
+When is the best time to build a home addition in Knoxville?
Based on NOAA 1991-2020 normals, the comfortable months for this kind of work are February through December. September and October are typically the driest of those months. Local contractors' schedules matter as much as the weather, so book early for the busy months.
Home addition near Knoxville
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.