Home addition cost in Rockford, IL
Local estimate from BLS wage data and BEA price levels. Reviewed Nov 4, 2026.
- Typical range (300 sq ft)
- $43,600 – $88,200
- Per sq ft
- $144 – $288
- before permit
- Versus US midpoint
- +15%
- US $57,500
- Rank of 300 metros
- #24
- 1 = most expensive
A home addition in Rockford, IL usually costs $43,600 to $88,200 for 300 sq ft. That works out to about $144 to $288 per sq ft before permits. Compared with the national midpoint that is $8,450 more. Carpenters earn a median of $34.99 an hour in the Rockford area, 20% above the US median of $29.12.
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Estimated cost for 300 sq ft in Rockford, IL, standard level
$57,000 to $74,800
About $187 to $245 per sq ft before permits. Labor is about 73% of the bill.
| Part | Low | High |
|---|---|---|
| Materials | $14,600 | $19,100 |
| Labor | $41,500 | $54,300 |
| Permits and fees | $880 | $1,450 |
| Total | $57,000 | $74,800 |
Cost breakdown for 300 sq ft in Rockford, IL
| Part of the job | Low | Midpoint | High | Share |
|---|---|---|---|---|
| Materials | $11,200 | $16,900 | $22,500 | 26% |
| Labor | $32,000 | $47,900 | $63,900 | 73% |
| Permits and fees | $460 | $1,150 | $1,850 | 2% |
| Total | $43,600 | $65,900 | $88,200 | 100% |
Where the Rockford price comes from
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, Rockford wages are 1.25 times the national level. Labor makes up about 73% of the midpoint estimate (67% at national prices).
Materials are scaled with BEA's regional price parity for goods. Rockford is at 93.6 against 100 for the US, so a materials line of $18,000 nationally becomes $16,900 here (midpoint, 300 sq ft). Permits follow the all-items index of 92.2: $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 Rockford. The wage table below marks each row.
Rockford: what basic, standard and premium work costs
The cited range is split into basic, standard and premium bands, then scaled to Rockford. 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
$43,600 to $61,500
Bump-out or simple room without plumbing
Standard
$57,000 to $74,800
Standard room addition with HVAC and electrical
Premium
$70,400 to $88,200
Large addition with bath or kitchen and a new foundation
| Size | Basic | Standard | Premium |
|---|---|---|---|
| bump-out (100 sq ft) | $14,900 – $21,200 | $19,600 – $25,900 | $24,300 – $30,600 |
| 20x20 room (400 sq ft) | $58,000 – $81,600 | $75,700 – $99,300 | $93,400 – $117,000 |
| large suite (600 sq ft) | $86,800 – $122,000 | $113,000 – $148,500 | $139,500 – $174,500 |
Related projects, priced for Rockford
Jobs that often go together with home addition are priced below at their usual sizes, using the same Rockford wage and price inputs. Compared with national midpoints, bathroom remodel comes out highest (+14%) and kitchen remodel lowest (+1%); the gap comes from the trades each job uses.
| Project | Size | Range | vs. US |
|---|---|---|---|
| Kitchen remodel | 120 sq ft | $18,600 – $31,600 | +1% |
| Bathroom remodel | 45 sq ft | $5,350 – $26,500 | +14% |
| Detached garage | 576 sq ft | $31,600 – $63,500 | +9% |
| Roof replacement | 2,000 sq ft of roof | $6,800 – $13,400 | +9% |
Rockford 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, Rockford Gtr Rockford Ap (5 miles from the city center). They are 30-year averages, so any one year can run hotter, colder or wetter.
For digging, grading and setting material in the ground, the comfortable months in Rockford are April through October: 7 of 12. Outside them, January, February, March, November and December have an average overnight low at or below freezing (32°F).
In January, February, March, November and December the average low is at or below freezing, which means frozen ground and slower digging, compaction and sod or stone placement. NOAA counts about 136 days a year with a low at or below 32°F at this station.
Rockford gets about 37 inches of precipitation in a normal year, including roughly 37 inches of snow. The wettest months are May, June and August (5.2 inches in June). Inside the workable window, September and October are the driest, at 3.6 and 2.6 inches. The station averages about 15 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 | 29 | 15 | 1.6 | Cold |
| Feb | 33 | 18 | 1.6 | Cold |
| Mar | 47 | 28 | 2.4 | Cold |
| Apr | 60 | 39 | 3.8 | Workable |
| May | 71 | 50 | 4.2 | Workable |
| Jun | 81 | 60 | 5.2 | Workable |
| Jul | 84 | 64 | 3.8 | Workable |
| Aug | 82 | 62 | 4.2 | Workable |
| Sep | 75 | 54 | 3.6 | Workable |
| Oct | 62 | 42 | 2.6 | Workable |
| Nov | 47 | 31 | 2.3 | Cold |
| Dec | 34 | 20 | 1.9 | Cold |
Rockford against nearby metros and the rest of Illinois
Of the five closest metros, all are cheaper than Rockford. Racine is the lowest at about $59,300 (midpoint, 300 sq ft), 70 miles away.
| Area | Range | Midpoint | vs. here |
|---|---|---|---|
| Rockford, ILthis page | $43,600 – $88,200 | $65,900 | |
| Janesville, WI25 miles | $43,100 – $87,100 | $65,100 | −1% |
| Madison, WI60 miles | $40,200 – $81,300 | $60,700 | −8% |
| Kenosha, WI60 miles | $40,100 – $81,100 | $60,600 | −8% |
| Racine, WI70 miles | $39,200 – $79,300 | $59,300 | −10% |
| Milwaukee, WI70 miles | $40,500 – $81,900 | $61,200 | −7% |
| Illinois (statewide) | $47,400 – $95,800 | $71,600 | +9% |
| United States | $38,000 – $77,000 | $57,500 | −13% |
Out of the 300 metros we cover, Rockford ranks #24 for the cost of this job (#1 is the most expensive). Statewide, Rockford is 8% below the Illinois figure.
Elsewhere in Illinois
| Metro | Size | Range | Midpoint | vs. here |
|---|---|---|---|---|
| Chicago, IL | 4,513,280 jobs | $49,000 – $99,000 | $74,000 | +12% |
| Peoria, IL | 166,020 jobs | $43,700 – $88,300 | $66,000 | level |
| Champaign, IL | 105,500 jobs | $42,500 – $85,900 | $64,200 | −3% |
| Springfield, IL | 100,810 jobs | $44,200 – $89,400 | $66,800 | +1% |
| Bloomington, IL | 88,110 jobs | $43,000 – $86,900 | $64,900 | −2% |
Metros of a similar size
Big cities and small ones price differently, so here is Rockford against the 4 metros with the closest total employment.
| Metro | Size | Range | Midpoint | vs. here |
|---|---|---|---|---|
| Cedar Rapids, IA | 139,260 jobs | $36,500 – $73,800 | $55,100 | −16% |
| Evansville, IN | 135,250 jobs | $39,500 – $79,800 | $59,700 | −10% |
| Huntington, WV | 140,740 jobs | $35,600 – $72,000 | $53,800 | −18% |
| Flint, MI | 135,040 jobs | $39,500 – $79,900 | $59,700 | −9% |
What local crews earn in Rockford
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 Rockford the blend is 1.25.
Carpenters (47-2031), 50% of the weighting: a median of $34.99 an hour, 20% above the US median of $29.12. The middle half of them earn between $27.33 and $47.16 an hour. About 810 work in the metro. That is 58.8 per 10,000 jobs, compared with 43.1 nationally, which suggests plenty of local crews to bid.
Cement masons and concrete finishers (47-2051), 10% of the weighting: a median of $36.21 an hour, 32% above the US median of $27.41. The middle half of them earn between $24.80 and $42.13 an hour. About 140 work in the metro. That is 10.2 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 $44.85 an hour, which is 48% above the national $30.38. The middle half of them earn between $35.68 and $51.27 an hour. BLS counts 370 of them working in the area, 26.9 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 $45.31 an hour, 48% above the US median of $30.67. The middle half of them earn between $30.80 and $56.91 an hour. About 440 work in the metro. That is 32.0 per 10,000 jobs, compared with 30.0 nationally, so the supply of crews looks typical.
Drywall and ceiling tile installers (47-2081) carry 10% of the labor weighting. BLS does not publish this trade for the Rockford metro, so we used the Illinois statewide median: $30.38 an hour against $28.33 for the US. The middle half of them earn between $24.78 and $49.27 an hour.
Roofers (47-2181), 10% of the weighting: a median of $31.30 an hour, 17% above the US median of $26.65. The middle half of them earn between $23.18 and $41.67 an hour. About 180 work in the metro. That is 13.1 per 10,000 jobs, compared with 8.7 nationally, which suggests plenty of local crews to bid.
A quick sensitivity check: moving the lead trade (carpenters) from the median to the 75th percentile wage adds about $8,000 to the midpoint estimate; the 25th percentile takes off about $5,050. That is a swing of roughly 7.6% to 12.1% of the total, which is useful for judging whether a bid reflects wages or something else, such as scope or margin.
Rockford has 137,650 jobs in total (BLS, May 2025), ranking 161st 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% | $27.33 | $34.99 | $47.16 | $29.12 | 1.20 | metro |
| Cement masons and concrete finishers (47-2051) | 10% | $24.80 | $36.21 | $42.13 | $27.41 | 1.32 | metro |
| Electricians (47-2111) | 10% | $35.68 | $44.85 | $51.27 | $30.38 | 1.48 | metro |
| Plumbers, pipefitters and steamfitters (47-2152) | 10% | $30.80 | $45.31 | $56.91 | $30.67 | 1.48 | metro |
| Drywall and ceiling tile installers (47-2081) | 10% | $24.78 | $30.38 | $49.27 | $28.33 | 1.07 | state |
| Roofers (47-2181) | 10% | $23.18 | $31.30 | $41.67 | $26.65 | 1.17 | metro |
| Blended | 100% | 1.25 | |||||
Specs and site conditions that change a Rockford bid
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.
Permits
Construction permits run $500-$2,000, or $5-$21 per $1,000 of project cost (HomeGuide).
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Home addition in Rockford: your questions
+How much does it cost to build a home addition in Rockford?
For 300 sq ft, expect $43,600 to $88,200 in the Rockford area. A standard-spec job lands at $57,000 to $74,800. Small jobs usually cost more per sq ft and large ones less.
+What is the price per sq ft for home addition in Rockford?
About $144 to $288 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 Rockford or Janesville?
Janesville is 25 miles away. The midpoint for 300 sq ft there is $65,100, which is 1% less than Rockford ($65,900). Wage and materials indexes both feed that gap.
+How much of the bill is labor in Rockford?
About 73% at the midpoint, or $47,900 out of $65,900. Materials are 26% and permits 2%. Nationally, labor is 67%.
+What would 20x20 room (400 sq ft) cost in Rockford?
$58,000 to $117,000. Pick a different size in the estimator above to get your own number.
+Does home addition need a permit in Rockford?
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 Rockford area (our national range of $500 to $2,000 scaled by the local price level).
+Is Rockford expensive for home addition compared with the rest of Illinois?
Rockford is 8% below the Illinois statewide estimate ($71,600 at the midpoint). We cover 6 metros in Illinois; see the state page to compare them.
+What do carpenters earn in Rockford?
The BLS median is $34.99 an hour in the Rockford area, compared with $29.12 nationally. The 25th to 75th percentile range is $27.33 to $47.16.
+What do basic and premium home addition work cost in Rockford?
For 300 sq ft, basic work runs $43,600 to $61,500 and premium work $70,400 to $88,200. 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 Rockford?
Based on NOAA 1991-2020 normals, the comfortable months for this kind of work are April through October. 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 Rockford
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.