Accessory Dwelling Unit Application Instructions

These instructions are provided to assist you in making an application for an Accessory Dwelling Unit (ADU), which is described in Section 10.814 – Accessory Dwelling Units of the Zoning Ordinance.

  1. Confer with Planning and Sustainability Staff: Meet with staff informally to discuss your potential ADU, explore options and to identify any concerns prior to making an application.

  2. Establish An Account in the City's Online Permitting Portal:  View Point Cloud is the software that powers the City of Portsmouth's online application center. In order to file an application for an ADU, you need to establish an account. When you register for the first time, you’ll need to access your email account in order to activate your View Point account.

    The person completing the online application should be the primary point of contact for the project. If not the owner of the property, an authorization from the property owner must be provide. All automatic notifications from View Point on the application’s status, approvals, and staff comments will only be sent to the email address of the primary point of contact and only this person can add additional information to the application once it’s been submitted.

  3. Complete a Land Use Application: Complete the Land Use Application form online and pay required application fee. Be sure to upload all supporting documents, plans, and exhibits. Those materials must be received by the Planning and Sustainability Department prior to the published deadline. 

    Submission fees are available from the Planning Department and online at Land Use Application Fees.

    If the project will need multiple land use approvals from different boards, a single online land use application record should be used for all of the approval permitting process.  

  4. Ensure Completeness: The Planning and Sustainability Department reserves the right to refuse applications that do not meet the minimum requirements.  Additional information and/or exhibits that illustrate the scope of the project may be requested by staff. 

    It is the obligation of the applicant to submit adequate plans and exhibits to demonstrate compliance with Section 10.814 of the Zoning Ordinance.  The applicant may use the City's online mapping program MapGeo and/or Assessor Data to help them provide, as a minimum, the following information:

    - Plan(s) showing existing and proposed conditions including:

    1.  Scale legend, title, address of project, date, source of displayed data.
    2.  Front, side and rear setback / yard dimensions and distance between buildings.
    3.  Lot dimensions.
    4.  Abutting street(s) and street names.
    5.  Dimensions (size and height) of single-family dwelling and other, if any, accessory buildings.
    6.  Labeled photo(s) of existing structures / buildings on property.
    7.  Scaled building plans and elevations of any proposed new construction or renovations.
    8.  Scaled floor plans of the proposed ADU that include total gross floor area and number of bedrooms.    
  5.  Provide Supporting Document: It is suggested that a detailed statement letter be provided by the applicant that explains the proposed ADU project and one that includes:   
    1. The principal and accessory dwelling units will remain under common ownership.
    2.  The principal or accessory dwelling shall be occupied by the owner of the dwelling as his/her principal place of residence.  (The owner will also provide an affidavit document that one of the units is his/her principal place of residence later in the application process).
    3.  Neither the principal nor accessory dwelling shall be used for any business, except that the owner may have a home occupation use in the unit that he or she occupies.
    4.  Where municipal sewer service is not provided, the septic system shall meet NH Water Supply & Pollution Control Division requirements for the demand for total occupancy of the premises.
    5. The accessory dwelling will not result in excessive noise, traffic, or parking congestion.
    6.  If applicable, a detailed explanation for any requests to the Planning Board to modify a specific dimension and/or parking standard

The Applicant is encouraged to consider the following when completing the application:

  • Provide neat and clearly legible materials. 
  • Use of color or highlights is encouraged in order to identify pertinent areas on submitted plans
  • Applicants are encouraged to review the application with a member of the Planning Department staff prior to submittal.
  • All applicants are encouraged to discuss the project with neighbors. 

For additional information on application requirements and the conditional use permit approval process, please refer to the City of Portsmouth Zoning Ordinance and the Planning Board Rules and Regulations or contact the Planning and Sustainability Department directly at (603) 610-7216.