Washington / Washington
Washington has 681,294 residents (ACS 2020-2024 5-year, table B01003, https://data.census.gov/table/ACSDT5Y2024.B01003?g=160XX00US1150000, checked 2026-10-19), about 11,146 people per square mile.
Washington is the city this door is named for; it covers 61.126 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).
The quote form takes a ZIP code; for Washington that is 20001, 20002, 20003, 20004, 20005, 20006, 20007, 20008 and 49 more (Census 2020 ZCTA to county subdivision and ZCTA to place relationship files, ZIP areas at least 20% inside the town, https://www2.census.gov/geo/docs/maps-data/data/rel2020/zcta520/tab20_zcta520_cousub20_natl.txt and https://www2.census.gov/geo/docs/maps-data/data/rel2020/zcta520/tab20_zcta520_place20_natl.txt, checked 2026-10-19).
11% of Washington homes are single-family detached, 10% are in two- to four-unit buildings and 57% are in buildings of five or more units (ACS 2020-2024 5-year, table B25024, https://data.census.gov/table/ACSDT5Y2024.B25024?g=160XX00US1150000, checked 2026-10-19).
With 57% of Washington homes in buildings of five or more units and 11% detached, the condo association usually decides where outdoor units can go, so that approval comes before the quote. With 58% of Washington homes rented (ACS 2020-2024 5-year, table B25003, https://data.census.gov/table/ACSDT5Y2024.B25003?g=160XX00US1150000, checked 2026-10-19), the landlord signs the quote in many of them.
Of the 324,491 occupied homes in Washington, 48% heat with natural gas, 1% with heating oil, 47% with electricity and 1% with propane (ACS 2020-2024 5-year, table B25040, https://data.census.gov/table/ACSDT5Y2024.B25040?g=160XX00US1150000, checked 2026-10-19).
Gas heats 48% of Washington against electricity at 47%, so most quotes here are a partial-home system that carries the shoulder seasons and the summer while the gas boiler stays for the deepest cold, or a whole-home system when the house is ready for it.
Washington has about the District of Columbia oil share of 1% and the same 47% electric share (ACS 2020-2024 5-year, table B25040, https://data.census.gov/table/ACSDT5Y2024.B25040?g=050XX00US11001, checked 2026-10-19).
No electric utility is on file for Washington on this door yet, so this page does not name one; the name on the bill decides which rebate path applies.
Washington has 361,014 housing units, 31% built before 1940 and 69% before 1980, with 24% built in 2000 or later (ACS 2020-2024 5-year, table B25034, https://data.census.gov/table/ACSDT5Y2024.B25034?g=160XX00US1150000, checked 2026-10-19).
The median Washington home was built in 1958 (ACS 2020-2024 5-year, table B25035, https://data.census.gov/table/ACSDT5Y2024.B25035?g=160XX00US1150000, checked 2026-10-19) and the median home has 3.9 rooms (ACS 2020-2024 5-year, table B25018, https://data.census.gov/table/ACSDT5Y2024.B25018?g=160XX00US1150000, checked 2026-10-19).
Heating design temperature: 14F. Source: ENERGY STAR Design Temperature Limit Reference Guide (2019 Edition), District of Columbia row, 99% heating, PDF page 17 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 14F figure is the District of Columbia cold-day number a Washington heat pump is sized against, so ask the installer to show the system's heating output at 14F, not at the milder rating-label temperature.
Ask whether the quote is whole-home or partial-home, because with 48% of Washington on gas and 47% already electric the two paths carry different rebate figures and different sizing.
Ask for the heat-loss calculation room by room; a Washington house from before 1940 (31% of the 361,014 units) rarely matches a square-footage rule of thumb.
The form on this page is the follow-up for Washington. The public number is the number the contractor quotes from.
No local contractor is named on this door for Washington yet. A request from this page goes to the first licensed shop that takes the door.