Appeal 33626

Building Code Guide 19-11: Townhouses

Townhouse with ADU: One or more townhouses in a townhouse structure may be constructed as an attached two-family dwelling. The second dwelling is called an ADU.

This appeal is a terminology change request - to allow the ‘townhome with ADU’ design requirements to be used for the design of an ‘over/under two-family townhouse,’ per review under the Residential code. The reason for the modification to terminology is to allow the home type in the CM3 zone and allow for the townhome to be considered two dwelling units per zoning code. The ADU designation is not allowed in the CM3 zone.

The townhomes were designed using the townhome code guide 19:11. The townhomes are not on their own lots, however, each has an implied property line and follows the requirements of R302.2 Townhouse separation wall assemblies. Specifically, using the modified two-hour wall assembly described in FIGURE R302.2.1(3). Additionally, the (4) over/under two-family dwellings are separated from each other by 1-hour horizontal and vertical assemblies.

The over/under two-family dwellings are connected to each other with a convenience door, which is a 60-minute rated/listed door, and located in a true 1-hour wall assembly. Separate egress is provided from each unit. The convenience door is not require egress and is provided with a privacy hardware set.

NFPA 13-D fire sprinklers will be installed throughout the over/under two-family townhomes.

The design has been reviewed with the residential plans examiner and the fire marshall through a preliminary fire-life safety meeting.

The reason for the modification is because “ADUs" are not allowed in the CM3 zone. The design complies with townhome code requirements for a two-family dwelling. If this project were in a residential zone, it would be allowed as designed and without appeal.