Building permits are required for all decks that are attached to the home or are 30 inches or more above grade. Decks and platforms not more than 30 inches above adjacent grade do not require a building permit.
If you want to build a deck that is attached to your home and it is over the 30", you will need to get a building permit. You will need to submit a Building Permit Application, a deck plan submittal checklist, a site plan and building plans.
The American Wood Council's "Design for Code Acceptance #6 - Prescriptive Residential Wood Deck Construction Guide" is a valuable resource that can be used to show code compliance for residential wooden decks. This guide includes tables for sizing all structural elements including footings. The sizing for wood members are based on exposure to exterior conditions and weather treatment of certain wood species, both of which reduce structural capacity.
Retaining walls less than four feet in height, including the 30” footing depth, do not require a building permit but must meet zoning setback requirements. To find out the setback requirements for your zone, please call the Planning at (801) 789-6617 or go HERE.
If you want to build a retaining wall that is more than four feet in height, you will need to get a building permit. You will need to submit a Building Permit Application, a site plan, and engineered building plans.