Mark Johnson Custom Homes is proud to introduce Wilmington's first LEED Platinum home. The Platinum rating is the highest green-building certification from the USGBC and validates our commitment to building safe, sustainable and efficient homes. The homeowner will enjoy over $2300 of annual utility savings, as well as save over 100,000 gallons of water annually. Water savings are achieved through invisible irrigation system, buried 1,800 gallon rainwater collection system, low flow fixtures and Kohler dual flush toilets. ICF concrete wall construction, Rinnai tankless water heater (natural gas), Bosch Energy Star appliances, 17 SEER Trane HVAC with ERV.