The small house icon is an indicator that you're connected to a Verizon Network Extender.
Click to enlarge source:androidcentral
They are primarily used for people that want to have Verizon Wireless service in their house, but there is no or very little network coverage in their area. They purchase the Network Extenders that hook up to their broadband connection and provide coverage for them. Someone in around you might have one of these extenders.
Source
Dialing #48 will give you a recording telling you if you're connected to a Network Extender.
Here's a picture of Network Extender
Click to enlarge