The ranking comes from a new study by Homeprotect, which highlights environmental and structural dangers including subsidence, ground movement, and escape of water. Over 10,000 properties have been purchased in the Harrow area over the past three years. "Checking for exposure to environmental or structural risks during the homebuying process is essential, as issues such as flood or subsidence may not be immediately apparent." This ground movement risk has been confirmed by separate research from Ground Sure. "Plus, some structural or environmental risks can make it more difficult to get home insurance due to the way insurers review the risk profile of a property.