William G. Day Company
HVAC contractor in Wilmington, DE 19804
About this company
William G. Day Company is listed as an HVAC contractor at 330 Water St in Wilmington, Delaware, in New Castle County. It is one of 9 HVAC companies in ZIP 19804.
Other HVAC companies nearby
Shellhorn & Hill501 S Market St, Wilmington
0.4 mi(302) 658-5293
Enhanced Heating and Air Conditioning1201 N Orange St Ste 700#757b, Wilmington
0.8 mi(302) 763-3960
Tri Elite Advisors Hvac225 7th Ave, Wilmington
0.8 mi(484) 347-5220
Moyer Indoor Outdoor - Services You Can Count On25 Brookside Dr, Wilmington
1.5 mi(302) 353-4404
One Hour Heating & Cooling410 Meco Dr, Wilmington
1.6 mi(302) 324-5998
Housing market around ZIP 19804
Figures describe the local area, not this company.
Typical home value$276,000−0.5% past year · +69% in 10 years
12-month value outlook+1.3%
Days to sale agreement15Philadelphia metro · 13 a year ago
New homes permitted, 20251,322New Castle County
Listings with a price cut26.3%Philadelphia metro
Sale price vs list100.1%Philadelphia metro
New construction sales229Philadelphia metro, Aug · −25% from last year
Source: Zillow (home values, rent, outlook and metro sales), data through Sep 2026. Permits: U.S. Census Bureau.
Typical home value, last 10 years
Source: Zillow Home Value Index, Sep 2026.
Local building angle: New Castle County permitted 1,322 new homes in 2025, including 188 apartment units. 4% of the homes in this ZIP were built since 2000.
Local figures are estimates from public records and Zillow housing data, updated regularly.