Permits are required for many home repair projects.
Each city, village, township, and county has their own requirements for pulling permits and it is good to be aware of what your municipality requires before beginning a project.
When working with contractors, make sure that they are aware of what permits are required for the work they are completing. A good idea is to ensure that the contractor's obligation to pull the necessary permits is written into the contracts before work begins.
A good rule of thumb is that if you are having electrical, mechanical, or plumbing work done or an addition added, you will need a permit. Any other work, such as driveways, roofing, siding, windows, garage work, masonry, waterproofing, interior remodeling, etc. may need a permit as well. The best way to find out is to contact your local building department.