Accessory buildings and uses: the 25%, the two storeys and the seven metres

It is Chapter 8.4 of Joint Regulation No. 9473, inside the buildability and construction volume. It establishes which uses may be accessory to a principal purpose permitted in the district, and with what height, occupancy, gross floor area and location parameters the accessory buildings housing them may be built. It is organised by the type of principal use: residential, commercial, marketing centre in a C-I district, industrial, and — in a closing section — institutional, tourist and anything else not covered earlier.

Accessory uses may be provided to any principal purpose permitted in the district where a property sits. Every accessory use permitted shall be clearly incidental and ordinarily related to the principal purpose it will serve, and must contribute to the comfort, convenience or need of the users of the principal purpose served. Every accessory use must be established together with, or after, the principal purpose is established, but never before. And discontinuing the principal purpose implies discontinuing the accessory uses, except for the dwelling units permitted in accessory buildings in residential districts.

• That the accessory use be clearly incidental and ordinarily related to the principal purpose, and contribute to its users’ comfort, convenience or need.Verified against the official source
• That the accessory use be established together with the principal purpose or after it, but never before.Verified against the official source
• For a professional office, home occupation or barbershop or beauty salon in a dwelling: that the space be no larger than twenty-five per cent of the gross floor area occupied by the dwelling unit; and if an accessory building is used, the lesser of that size and the occupancy percentage permitted to that building.Verified against the official source
• That the district’s residential characteristics be maintained, avoiding any impression that the property is occupied for a purpose other than the permitted dwelling, with the exception of the sign permitted for the accessory use.Verified against the official source
• That the total occupancy of the main and accessory buildings not exceed the district’s permitted figure, and that the accessory building’s not exceed twenty-five per cent of the main building’s area or fifteen per cent of the lot area, whichever is less.Verified against the official source
• That an accessory building built up to the lot line keep not less than one and a half metres of separation from the main building; if sited closer than that, it must observe the yards required for the district.Verified against the official source

• The chapter lists no documents of its own: it fixes uses and parameters. The documents are those of the corresponding construction or use permit process before OGPe or the hierarchy I-III autonomous municipality.

1. 1

   Step 1: The five rules that explain everything

   Before looking at a single figure it pays to understand the logic, because almost every refusal comes from here. Accessory uses may be provided to any principal purpose permitted in the district. Every accessory use shall be clearly incidental and ordinarily related to the principal purpose it will serve. It must contribute to the comfort, convenience or need of that principal purpose’s users. It must be established together with the principal purpose or after it, but never before: you do not build the accessory building first and the house afterwards. And discontinuing the principal purpose discontinues the accessory uses, with a single exception — the dwelling units permitted in accessory buildings in residential districts.

2. 2

   Step 2: The office or studio of whoever lives there

   Where space is provided on the property for a professional office or a resident’s studio, as an accessory use to a permitted dwelling unit, the space shall be no larger than twenty-five per cent of the gross floor area occupied or used by that dwelling unit. If a building is used for that purpose, the size is the lesser of that twenty-five per cent and the occupancy percentage permitted to that accessory building. In connection with these activities only family members residing in the dwelling unit may be used, except in the practice of a profession, where one private person could be employed; and in every case the services rendered shall be those the resident responsible for the studio or office produces. The district’s residential characteristics are maintained, with the exception of the sign permitted for this accessory use.

3. 3

   Step 3: The home occupation and the sentence that limits it

   The home occupation carries the same twenty-five per cent cap and the same lesser-of-the-two rule. But it adds three conditions of its own. Only family members residing in the dwelling unit may be used, and mechanical equipment in ordinary household use for purely domestic purposes. The services rendered or articles sold shall be those the family members residing there produce. And one short sentence settles many cases: "No site or space shall be provided or maintained for the sale of food or drink." As with the office, the property’s residential characteristics are maintained, with the exception of the permitted sign.

4. 4

   Step 4: Barbershop or beauty salon: a single chair

   Same twenty-five per cent cap and same lesser-of rule. And two conditions people often forget: in connection with operating these uses only one chair may be used, and the operator must reside in the dwelling unit they will be accessory to. The services rendered or articles sold shall be those the operator who inhabits the dwelling unit produces. Residential characteristics are maintained, with the exception of the permitted sign.

5. 5

   Step 5: The efficiency out back: up to two units

   Providing dwelling units in accessory buildings, except in R-U and R-T districts, is permitted as an accessory use where dwelling units exist in the main building, provided the property’s population density conforms to the district’s and the number of dwelling units in the accessory building is not greater than two. And there is an extra rule hidden in the gross-floor-area paragraph: an accessory building’s second storey may be occupied or used exclusively for dwelling units, provided the number of bedrooms is not greater than three and each is no larger than twelve feet by twelve feet, and the additional rooms include only a living room, dining room, kitchen, bathroom and one balcony per permissible dwelling unit. Remember too the exception in Rule 8.4.1: these dwelling units are the one thing that is not discontinued when the principal use ceases.

6. 6

   Step 6: Height, occupancy and gross floor area

   Accessory buildings to a principal residential use may not have more than two storeys or exceed seven metres in height, or the height of the main building they serve — whichever applies — except buildings for agricultural uses permitted in the districts, whose heights are set by the use’s particular conditions. Occupancy has two limits applying at once: the total occupancy of the main and accessory buildings shall not exceed the district’s permitted figure, and the accessory building’s occupancy shall not exceed twenty-five per cent of the main building’s area or fifteen per cent of the lot area, whichever is less. Gross floor area for accessory buildings is twice the occupancy area.

7. 7

   Step 7: Where it may go: the 60%, the 40% and the metre and a half

   Accessory-use spaces may be provided as part of a main building or in accessory buildings, and those may sit, unless the regulation says otherwise, in any section of the lot where the main building may be located, or in required side or rear yards, with conditions. On interior lots they may sit in those yards provided they are built at a distance from the road line of not less than sixty per cent of the lot’s depth; and where the lot’s depth is greater than the district requires, a setback equal to the required percentage multiplied by that district’s minimum lot depth is allowed. On corner lots or lots fronting two or more roads, beyond the sixty per cent, not less than forty per cent of the distance between the road line and its corresponding opposite side of the lot is required, where that distance is not the depth. And in every case: accessory buildings built up to the lot line shall be separated from the main building by not less than one and a half metres; if one is to sit closer than that, it must observe the yards required for the district.

8. 8

   Step 8: Commerce: storage, motors and compressors

   On the commercial side, storage as an accessory use rises: the space shall be no larger than fifty per cent of the gross floor area occupied or used for the principal purpose, with the same lesser-of rule where an accessory building is used. And there is a rule that settles many neighbour complaints: motors, electrical substations and compressors or refrigeration units must be located as part of the main building without protruding from its general lines; where the primary use’s nature makes that impossible, siting them in separate structures may be allowed, provided a separation of not less than ten feet from any side or rear boundary line of the lot is observed. Height remains two storeys and seven metres, or the main building’s, save in extensive commercial recreation projects, where the Adjudicative Board sets it on the basis of the adequate functioning of the principal uses and the public’s safety and comfort. In commerce developed under Chapter 5.1, accessory-use spaces are located as an integral part of the main building.

9. 9

   Step 9: Marketing centre in a C-I district: no franchise buildings

   Here accessory buildings may be dedicated only to services; simple commercial recreation; trade in tyres, accessories and motor vehicle parts and light mechanics; restaurants, including fast food; and retail sales. They may not exceed five metres in height. Occupancy and gross floor area shall be no greater than fifty per cent of that permitted in the main building. They may sit in any of the yards required for the marketing centre, observing minimum yards of fifteen metres from any boundary and a setback of not less than fifteen metres from the main building and from any other accessory building. For accessory uses, the required parking must be provided independently of that provided for the main building. And an unusual design rule: to keep the same architectural vocabulary, every accessory building must conform to the marketing centre’s main building’s general architecture; generic buildings, or ones symbolically or visually representing a franchise, are not permitted, and only limited use of corporate identity features through signage is allowed.

10. 10

    Step 10: Industry, and everything else

    On the industrial side, accessory storage has the same fifty per cent cap, but with a valve: OGPe may authorise a larger storage space where the nature of the industrial use to be established justifies it. Facilities for a watchman or guard employed on the property are permitted as an accessory use where a district-permitted industrial use operates there. Accessory buildings may not exceed five metres in height, and their occupancy and gross floor area, combined with the main building’s, shall not exceed the district’s maximum percentages. Location follows the same sixty, forty and metre-and-a-half rules. And the last section picks up what did not fit before: accessory uses and buildings for institutional, tourist and other uses not covered are authorised by OGPe’s Adjudicative Board or the hierarchy I-III autonomous municipality, adjusting to the height, occupancy, gross floor area and location parameters established for residential uses.

Before OGPe or the hierarchy I-III Autonomous Municipality, as applicable, within the construction or use permit process. In extensive commercial recreation projects, the Adjudicative Board sets accessory buildings’ height and OGPe’s Executive Director their occupancy area, both on the basis of the adequate functioning of the permitted principal uses and the public’s safety and comfort. Institutional, tourist and other accessory uses and buildings not covered are authorised by OGPe’s Adjudicative Board or the hierarchy I-III municipality.

• Building the accessory building before the principal one: the regulation says "never before".
• Going over twenty-five per cent of the dwelling’s gross floor area in the office, home occupation or salon.
• Putting more than one chair in the accessory barbershop or salon, or having the operator not live in the house.
• Keeping a site or space for selling food or drink inside a home occupation.
• Putting more than two dwelling units in the accessory building, or attempting it in an R-U or R-T district.
• Applying only one of the two occupancy caps: the district total and the 25%/15%-whichever-is-less both apply.
• Building up to the lot line closer than a metre and a half to the main building without observing the district’s yards.
• Moving motors, substations or compressors out of the main building without the ten feet from any side or rear boundary.

These are the government pages this guide is based on.

• Oficina de Gerencia de Permisos (OGPe)

  OGPe

  docs.pr.gov

• Permit Management Office

  ogpe

  ogpe.pr.gov