Charleston / Union
Union has 8,079 residents (give or take 34) (ACS 2020-2024 5-year, table B01003, https://data.census.gov/table/ACSDT5Y2024.B01003?g=160XX00US4573105, checked 2026-10-19), about 990 people per square mile.
Union is about 162 miles from the Census center point for Charleston in a straight line and covers 8.164 square miles of land (Census 2024 Gazetteer internal points and land area, https://www2.census.gov/geo/docs/maps-data/data/gazetteer/2024_Gazetteer/, checked 2026-10-19).
Of the 3,904 occupied homes in Union, 45% heat with natural gas, 0% with heating oil, 53% with electricity and 1% with propane (ACS 2020-2024 5-year, table B25040, https://data.census.gov/table/ACSDT5Y2024.B25040?g=160XX00US4573105, checked 2026-10-19).
Electricity already heats 53% of Union homes, ahead of gas at 45%, and a home on electric baseboard sees the biggest bill change from a heat pump because it replaces resistance heat one for one.
Union has about the Union County oil share of 1% and 5 points less electric heat than the county's 58% (ACS 2020-2024 5-year, table B25040, https://data.census.gov/table/ACSDT5Y2024.B25040?g=050XX00US45087, checked 2026-10-19).
Union has 4,388 housing units, 21% built before 1940 and 82% before 1980, with 5% built in 2000 or later (ACS 2020-2024 5-year, table B25034, https://data.census.gov/table/ACSDT5Y2024.B25034?g=160XX00US4573105, checked 2026-10-19).
Union has 6 points more pre-1940 homes than Union County as a whole (15%) and 8 points fewer homes built after 2000 than the county's 13% (ACS 2020-2024 5-year, table B25034, https://data.census.gov/table/ACSDT5Y2024.B25034?g=050XX00US45087, checked 2026-10-19). An older stock means more insulation upgrades before the heat pump goes in.
The median Union home was built in 1965 (ACS 2020-2024 5-year, table B25035, https://data.census.gov/table/ACSDT5Y2024.B25035?g=160XX00US4573105, checked 2026-10-19) and the median home has 5.2 rooms (ACS 2020-2024 5-year, table B25018, https://data.census.gov/table/ACSDT5Y2024.B25018?g=160XX00US4573105, checked 2026-10-19).
65% of Union homes are single-family detached, 11% are in two- to four-unit buildings and 15% are in buildings of five or more units (ACS 2020-2024 5-year, table B25024, https://data.census.gov/table/ACSDT5Y2024.B25024?g=160XX00US4573105, checked 2026-10-19).
50% of Union homes are rented (ACS 2020-2024 5-year, table B25003, https://data.census.gov/table/ACSDT5Y2024.B25003?g=160XX00US4573105, checked 2026-10-19), so beside the 65% detached houses there is a real share of jobs where the landlord, not the resident, signs the quote.
Union has 10 points more five-plus-unit buildings than the county's 5% (ACS 2020-2024 5-year, table B25024, https://data.census.gov/table/ACSDT5Y2024.B25024?g=050XX00US45087, checked 2026-10-19).
50% of Union homes are rented (ACS 2020-2024 5-year, table B25003, https://data.census.gov/table/ACSDT5Y2024.B25003?g=160XX00US4573105, checked 2026-10-19), so the market splits between resident-led jobs where the occupant picks the system and landlord-led jobs where they do not, and the rebate paperwork differs.
82% of Union homes were built before 1980 and only 5% in 2000 or later (ACS 2020-2024 5-year, table B25034, https://data.census.gov/table/ACSDT5Y2024.B25034?g=160XX00US4573105, checked 2026-10-19), so most of the stock predates modern insulation codes; the installer's heat-loss calculation, not a square-footage rule, decides the tonnage.
No electric utility is on file for Union on this door yet, so this page does not name one; the name on the bill decides which rebate path applies.
Median household income in Union is $31,914 (ACS 2020-2024 5-year, table B19013, https://data.census.gov/table/ACSDT5Y2024.B19013?g=160XX00US4573105, checked 2026-10-19); many state and utility heat pump rebate programs set higher incentive tiers for income-qualifying households, so the household income on the application, not the town median, decides which level applies.
Heating design temperature: 22F. Source: ENERGY STAR Design Temperature Limit Reference Guide (2019 Edition), Union County row, 99% heating, PDF pages 105 to 107 of 141 (Revised 11/11/2020), https://www.energystar.gov/sites/default/files/Design%20Temperature%20Limit%20Reference%20Guide%20(2019%20Ed)%20-%20ENERGY%20STAR%20Single-Family%20New%20Homes_Rev11.pdf, fetched 2026-10-19, 99%.
That 22F figure is the Union County cold-day number a Union heat pump is sized against, so ask the installer to show the system's heating output at 22F, not at the milder rating-label temperature.
Ask for the heat-loss calculation room by room; the median Union home has 5.2 rooms and was built around 1965, and the count of heads and the tonnage follow the rooms and the insulation, not the square footage.
The form on this page is the follow-up for Union. The public number is the number the contractor quotes from.
No local contractor is named on this door for Union yet. A request from this page goes to the first licensed shop that takes the door.