Investing in a home renovation project not only requires money, but also time and patience. While contractors, architects and designers can estimate how long a project may take, it is impossible to anticipate all of the scenarios that can affect that estimated timeline. Information from the real estate firm Keller Williams indicates an average kitchen remodel involving installation of new countertops, cabinets, appliances, and floors can take three to six months. But if ductwork, plumbing or wiring must be addressed, the job may take longer. A midline bathroom remodel may take two to three months. Adding a room to a house can take a month or two. The home improvement resource Renovation Junkies offers similar estimates, with the average home renovation taking between four and eight months. Homeowners need to consider time when planning their home projects.