Building codes and permits
Probably every American city enforces a building code, most of which follow a uniform code published by an independent council. Building codes ensure that the structure is stable, materials are relatively fire resistant, that plumbing and electricity are sufficient, and that people can move in, out, and around in the building. These codes are strictly enforced and allow for very little exception. If one of these codes is deemed applicable to a proposed intervention, one should expect to closely adhere to its standards. Violations of building codes can result in fines and, eventually, condemnation and seizure by public authorities.
Building codes are enforced by a city’s building inspectors and code enforcement officers. These officials decide whether a structure meets the standards required by that town. These codes not only cover permanent buildings but they also regulate structures that are temporary, in the public right-of-way, or use innovative materials. These are where DIY activity is most likely to encounter the building code. The building code allows for temporary structures (which stand for less than 6 months) as long as they still meet all standards for structural stability, fire safety, entries and exits, lighting, ventilation, and sanitation. If you want to erect a temporary structure, you will probably need to get approval from the building inspector. You will be required to submit a site plan showing the structure and its relationship to property boundaries, as well as provide the designed occupant load (the number of intended users) and adequate exits. This can be a high bar to achieve without the help of a professional structural engineer! (However, you may be able to avoid some of these rules if the structure is less than 120 square feet – a little more than 10 feet wide by 10 feet long – or designed for fewer than 10 people.)
The building code also regulates any structure that reaches into public space known as rights-of-way. Generally, any structure below 8 feet in height cannot intrude into space such as a sidewalk unless it is a step or an architectural feature like a column, sill, or lentil. Even then these encroachments are limited to less than 12 inches. Certain locations may be even stricter: in Raleigh, N.C., posts and columns are not allowed at all within the right-of-way or sidewalk. Though you probably intend your intervention to engage the public realm, care must be taken along the boundaries between public and private space, lest your project be removed by city officials. Finally, if your project uses uncommon construction materials or techniques, you may have to prove its safety by obtaining a load test from a professional engineer.
Building permits are the first step in complying with a building code. Most types of building or site work require a building permit before it can begin. The main exceptions are accessories to houses such as detached tool sheds, playground equipment, and inflatable pools. Permit applications require a description of the work, drawings or plans, and the signatures of relevant licensed professionals such as a construction contractor, architect, or structural engineer. The building permit is time-limited: a project must be started and completed within the approved timeframe or an extension or new permit will be required. All new buildings and structures, as well as changes to a building or structure that change its fundamental classification, also require a certificate of occupancy before the work is considered complete and people may inhabit the space. These involve an inspection by a city official when work is nearly complete.
All this talk of buildings and structures begs the question, what counts as a building or structure? The standard building code defines a building quite simply as “any structure used or intended for supporting or sheltering any use or occupancy.” In Raleigh’s code of ordinances, a building is defined as “any structure, place, or any other construction built for the shelter or enclosure of persons, animals, chattels or property of any kind or any part of such structure, shelter or property.” A structure is “anything constructed or placed upon a property which is supported by the ground or which is supported by any other structure.” In other words, a building provides shelter to people and things, while a structure is more broadly anything that rests on the ground or another structure.