How old are the homes in Harlem Township (Winnebago County), IL?

Name: Age of homes in Harlem Township (Winnebago County), IL, 2020–2024
Creator: US Census Bureau
License: https://www.census.gov/data/developers/about/terms-of-service.html

41.0% (±3.5 points) of the homes in Harlem Township (Winnebago County), IL were built before 1980 (2020–2024 American Community Survey).

2.5% were built before 1940.

6.1% were built in 2010 or later.

Figures last updated on November 12, 2026.

Built before 1980: 41.0% (±3.5 points)
Built before 1940: 2.5%
Built 2010 or later: 6.1%

When the homes in Harlem Township (Winnebago County) were built

Housing units by year structure built, 2020–2024
Year built	Harlem Township (Winnebago County)	Winnebago County	Illinois	United States
2020 or later	1.2% (±0.7 points)	0.3%	0.7%	2.0%
2010 to 2019	4.9% (±1.3 points)	2.3%	5.0%	9.4%
2000 to 2009	17.1% (±2.2 points)	11.0%	11.2%	13.6%
1990 to 1999	20.9% (±2.4 points)	12.4%	10.5%	12.4%
1980 to 1989	14.9% (±1.9 points)	10.5%	9.2%	12.9%
1970 to 1979	15.7% (±2.2 points)	15.0%	14.2%	14.2%
1960 to 1969	10.0% (±1.7 points)	13.0%	11.5%	9.9%
1950 to 1959	9.2% (±1.6 points)	13.8%	11.9%	9.5%
1940 to 1949	3.6% (±1.0 points)	6.2%	5.6%	4.4%
1939 or earlier	2.5% (±1.0 points)	15.5%	20.2%	11.7%

In Harlem Township (Winnebago County), the share of homes built before 1980 is lower than in Winnebago County (63.5%).

It is also lower than in Illinois (63.4%).

It is lower than the national figure (49.7%).

In Winnebago County, Harlem Township (Winnebago County) ranks 20 of 26 places with a published estimate, from highest to lowest share of homes built before 1980.

Statewide, it ranks 2397 of 2,751.

Rankings use the estimates alone; where margins of error overlap, neighboring ranks may not truly differ.

Why the age of a home matters: lead-based paint

Federal law treats housing built before 1978 as likely to contain lead-based paint.

Before a lease or sale of most pre-1978 housing, the landlord or seller must disclose any known lead-based paint and hazards and give the tenant or buyer the EPA pamphlet (42 U.S.C. § 4852d; 40 CFR part 745, subpart F; 24 CFR part 35, subpart A).

A contractor paid to renovate, repair or paint a pre-1978 home must be a certified firm, use a certified renovator and follow lead-safe work practices under the Renovation, Repair and Painting Rule (40 CFR part 745, subpart E) whenever the job disturbs more than 6 square feet of painted surface in a room or more than 20 square feet outside; window replacement and demolition always count (40 CFR 745.83).

Certification comes from EPA, or from the state where EPA has authorized the state to run the program.

The Census Bureau groups construction by decade, so the share built before 1978 lies between the share built before 1970 (25.3%) and the share built before 1980 (41.0%).

Homes built before 1980 in places near Harlem Township (Winnebago County)

Nearest places with a published estimate, compared with Harlem Township (Winnebago County)
Place	Distance	Homes built before 1980	Compared with this place
Harlem Township (Winnebago County)	—	41.0% (±3.5 points)	—
Loves Park	1.9 mi	41.6% (±4.4 points)	Not measurably different
Machesney Park	2.2 mi	54.4% (±5.3 points)	Higher
Caledonia Township	4.2 mi	16.5% (±7.1 points)	Lower
Caledonia	4.5 mi	76.6% (±33.3 points)	Higher
Roscoe	4.5 mi	9.1% (±3.4 points)	Lower
Candlewick Lake	5.8 mi	17.2% (±9.7 points)	Lower
Roscoe Township	6.0 mi	26.4% (±4.5 points)	Lower
Timberlane	6.2 mi	18.6% (±14.6 points)	Lower

Nearby places with a measurably lower figure: Caledonia Township, IL (16.5%), Roscoe, IL (9.1%), Candlewick Lake, IL (17.2%).

Nearby places with a measurably higher figure: Machesney Park, IL (54.4%), Caledonia, IL (76.6%).

Distance is measured in a straight line between the Census Bureau’s internal points for each place.

Homes built before 1980 across Winnebago County, place by place

Rank	Place	Homes built before 1980
14	Winnebago Township	47.6% (±9.0 points)
15	New Milford	44.9% (±16.8 points)
16	Rockton Township	44.7% (±6.0 points)
17	Winnebago	43.7% (±8.6 points)
18	Laona Township	42.3% (±22.4 points)
19	Loves Park	41.6% (±4.4 points)
20	Harlem Township (Winnebago County)	41.0% (±3.5 points)
21	South Beloit	40.9% (±9.9 points)
22	Roscoe Township	26.4% (±4.5 points)
23	Rockton	23.1% (±6.2 points)
24	Cherry Valley	21.2% (±7.3 points)
25	Roscoe	9.1% (±3.4 points)
26	Westlake Village	0.0% (±15.7 points)

Showing 13 of 26 places in Winnebago County, ranked from highest to lowest.

Survey years: 2020–2024 (American Community Survey 5-year estimates).

Margins of error are at the 90% confidence level.

What you can do on Seayora in Harlem Township (Winnebago County)

One account for renting, owning, managing and fixing homes, with these figures beside you.

Do repairs, renovations or maintenance?

Get found by owners and renters near Harlem Township (Winnebago County), and send estimates and invoices from your phone.

Join as a pro · Find a pro

Own or manage a rental?

List it, sign the lease and collect rent online, with the figures for Harlem Township (Winnebago County) beside you.

Create a landlord account · See what landlords get

Looking for a place to rent?

Browse homes for rent near Harlem Township (Winnebago County), save the ones you like and apply online.

Browse rentals · Create a renter account

Questions about Harlem Township (Winnebago County)

How old are most homes in Harlem Township (Winnebago County)?

41.0% of homes in Harlem Township (Winnebago County), IL were built before 1980 (2020–2024 American Community Survey).

Do homes in Harlem Township (Winnebago County) need a lead paint disclosure?

A home built before 1978 does, before it is rented or sold, unless an exemption applies (42 U.S.C. § 4852d); between 25.3% and 41.0% of homes in Harlem Township (Winnebago County) were built before then.

Does a contractor need lead certification to work on older homes in Harlem Township (Winnebago County)?

Yes, when the job disturbs more than 6 square feet of paint in a room or 20 square feet outside, or replaces a window: the firm must be certified and a certified renovator must direct the work under the Renovation, Repair and Painting Rule (40 CFR part 745, subpart E).

Sources

Selected Housing Characteristics (DP04), 2020–2024 ACS 5-year estimates — Harlem township, Winnebago County, Illinois

To check these figures in the Census Bureau’s own API, request the variables below from the 2024 ACS 5-year data profile (acs/acs5/profile) for Harlem township, Winnebago County, Illinois (county subdivision:32928, in state:17 county:201).

Each estimate (E or PE) has a margin of error beside it (M or PM).

The API needs a free key.

Request a Census API key.

DP04_0017PE, DP04_0017PM, DP04_0018PE, DP04_0018PM, DP04_0019PE, DP04_0019PM, DP04_0020PE, DP04_0020PM, DP04_0021PE, DP04_0021PM, DP04_0022PE, DP04_0022PM, DP04_0023PE, DP04_0023PM, DP04_0024PE, DP04_0024PM, DP04_0025PE, DP04_0025PM, DP04_0026PE, DP04_0026PM

This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.

Figures are published by the US Census Bureau, HUD, the Bureau of Labor Statistics and the FBI; Seayora reproduces them and does not adjust them, except where a sentence says it compares dollar figures after inflation. They describe the whole place, not any one building or street, and are not an appraisal, a rent determination, a tax bill, a safety rating or legal advice.