Location: 0 Wildwood Street, Dorchester, Boston, MA 02126
Project Type: New Construction – 3-Story, 3-Unit Multifamily (Triple Decker)
Scope: MEP Engineering | Fire Sprinkler Design | Fire Alarm System Design | Energy Compliance
Project Area: ~4,000 sq. ft. | 4 Bedrooms | 3 Parking Spaces
Completion Stage: Construction Documents – 2025
Code Compliance: NFPA 13D, 780 CMR (10th Ed.), MA Stretch Code, IECC 2021
Project Summary
This project involved the complete mechanical, electrical, plumbing (MEP), and fire protection design for a new 3-story triple decker multifamily building in the Dorchester neighborhood of Boston, MA. Located on a tight urban infill lot, the building includes three residential units, one of which is a Group 1 accessible unit on the ground floor, as required by 521 CMR. The design integrates NFPA 13D fire sprinkler systems and a code-compliant hardwired fire alarm system, aligned with Boston and Massachusetts state regulations.
Engineering Scope of Work
MEP Design
- HVAC: High-efficiency, ducted mini-split systems were specified per IECC 2021 standards for Climate Zone 5A. Each unit features independent temperature control with smart thermostats positioned per accessibility standards.
- Plumbing: Domestic water and sanitary system layouts were coordinated with tight vertical shafts. Fixture counts align with 248 CMR plumbing code for multifamily use.
- Electrical: Dedicated branch circuits were designed for all major appliances, including in-unit laundry and HVAC equipment. Panels sized to support residential load with arc-fault and ground-fault protection where required.
Fire Protection Systems
- Sprinkler System: Designed to NFPA 13D standards for residential buildings under 12,000 SF. The layout ensures full coverage of all living areas, utility rooms, and attic spaces. Hydraulic calculations were performed to verify system adequacy using city water supply pressure and flow data.
- Fire Alarm System: A hardwired, interconnected smoke and CO detection system was designed per 527 CMR and NFPA 72. The system includes:
- Photoelectric smoke detectors in all sleeping and common areas.
- Heat detectors in mechanical and laundry rooms.
- Integrated battery backup across devices.
- Egress notification via horn/strobe units in compliance with the life safety egress code.
Code & Regulatory Compliance
The design meets or exceeds the following code requirements:
- Massachusetts Building Code (780 CMR, 10th Edition) – Based on 2021 IBC.
- NFPA 13D – Automatic sprinkler system for low-rise residential.
- NFPA 72 – Fire alarm systems for multifamily occupancy.
- 527 CMR – Massachusetts Fire Code.
- 521 CMR – Accessibility provisions for Group 1 units.
- 2021 IECC + MA Stretch Code – For building envelope and HVAC energy performance.
Project Highlights
- Building Type: Type VA protected wood-frame, R-2 residential occupancy.
- Total Conditioned Area: ~3,950 sq. ft.
- Life Safety Design: Modeled using architectural life safety plans (Ref. A1.03), including occupancy load (15 occupants), egress width, fire-rated partitions, and stairwell clearances.
- Energy Efficiency: HVAC and envelope design aligned with thermal performance targets for multifamily low-rise in Climate Zone 5A.
- Accessibility: One fully accessible unit on the ground level with compliant clearances, reach ranges, and bathroom fixtures per 521 CMR.
Permit-Ready: All systems designed in compliance with Boston Zoning Article 60 and approved for schematic-level code review.
