How do engineers expand roads to create new lanes without moving the houses/businesses that already exist along the side of the road?

Question

For example, how do engineers create 6+ lanes where there were only 4 before? How are they able to create additional lanes when there are solid structures that exist close to where the old lanes were?

In: Engineering

Answer 1

A lot of roads were originally built with space in the middle, and breakdown lanes and more space on the outside. That can be converted into additional traffic lanes.