It depends
united-statesnew-jersey
I will give you some examples from engineering land development to illustrate what I mean.
Regulations state what you CAN do
So a lot of zoning ordinances state explicitly what a parcel of land in that zone can be used for. For example, in the City of Camden's zoning code explicitly states what you can do in the R-2 zone (§870-52):
Principal Uses:
- Single-family detached dwellings.
- Semidetached dwellings.
- Duplex (two-family) dwellings.
- Townhouse (attached/row) dwellings.
- Buildings, structures, and other uses owned and operated by the City of Camden for municipal purposes.
- Parks, playgrounds, or recreation areas, community center buildings, and libraries.
- Public, private, or parochial educational institutions.
Accessory Uses:
- In-ground and aboveground swimming pools and/or other structures customarily incidental to a private swimming pool on a property,
subject to the requirements of § 870-193.
- Accessory buildings and structures, subject to the requirements of § 870-189.
- Off-street parking and private garages, subject to the requirements of § 870-214 and 870-230 through 870-241.
- Fences and walls, subject to the requirements of § 870-197.
- Signs, subject to the requirements of § 870-253.
- Porches, decks and patios, subject to the requirements of § 870-190.
So if you are trying to do something that's not on that list, you can't do it without permission. And if you are doing something on that list, your approvals process is a lot easier because you don't need that permission.
The stringent nature of zoning rules also should not be understated. For example, although off-street parking is a permitted Accessory Use, it's not a permitted Principal Use. Therefore, if you try and convert an existing lot in the R-2 zone into a parking lot as the only use (i.e. the Principal Use), you would need a special permit for that.
Regulations state what you CAN'T do
Elsewhere in that zoning code are rules about parking requirements. Specifically in §870-231B(1), the code states the following for when you CAN'T use compact car parking:
The width of all aisles providing direct access to individual parking stalls shall be in accordance with the requirements set forth below. Compact car spaces may be permitted by the Planning Board only where the total number of spaces proposed to be provided exceeds 50 and shall not exceed 30% of the total number required. If permitted, compact car parking spaces shall be clearly identified by markings and/or signage and shall be grouped in one or more locations rather than dispersed throughout the site.
These rules more or less stipulate that a Planning Board can't approve a parking lot with compact car spaces if the lot has 50 or fewer spaces. So if you wanted to get approval for such a lot, you'd have to seek approval from the Zoning Board (that's not explicitly stated, but when you learn land use law, if the Planning Board can't do something then the power usually goes to the Zoning Board).
Regulations provide guidelines
For land use purposes, this is generally only the purview of professionals to handle, but there are lots of regulations which more or less provide boundaries for Professional Engineers, Environmental Scientists, Surveyors, Architects, Planners, etc. to work within. For example, the State of New Jersey's stormwater rules operate in such a manner. The overall rule requirements are stipulated in NJAC 7:8, however, actual implementation of the rule needs to conform with the State's Best Management Practices (BMP) Manual.
I won't go much into specifics regarding the BMP Manual other to say it's hundreds of pages describing the various ways the State permits stormwater designs to demonstrate compliance with NJAC 7:8 and the features that can be used to achieve that. But the actual choice of features, where they are placed on the site, and just about every other design element is determined by the professional performing the design and regulators are only limited in their scope to affirming that the proposed design conforms with the applicable rules.
In general, regulations are written in a way to achieve some particular goal and often do so by either stating what you can't do, by stating what you can do (which in a way says that you can't do anything else), or by providing guidelines.
I will say that if your situation falls into the first two categories, the issue is cut and dry. If you fall into the guidelines category you then need to see if the rules you have to follow provide for resolving disputes. NJAC 7:8 states that if you need to deviate from strict conformance with it, then you need to seek a variance or waiver. I will also say that the granting of such a waiver is going to hinge on the opinion of the professional reviewing it. Generally, when we have to go through this process, it comes down to both the design engineer and the review engineer sitting down and discussing things in technical detail and coming to an agreement.
Once that's figured out, the recommendation to approve is given to the regulatory body and they default approve it. The reason for the default approval is none of the members of the Planning Board are as qualified as the review engineer to determine if granting the waiver is appropriate.