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Case Study

Ditmas Park Passive Home Renovation.

Ditmas Park, Brooklyn | Full structural engineering for a major residential renovation, rear expansion, foundation work, underpinning and SOE.

Ditmas Park passive home renovation

Project Overview

A Major Residential Renovation Designed Around Existing Conditions.

H&Z Consulting Engineering provided full structural engineering services for a major renovation and expansion project in Ditmas Park, Brooklyn. The scope involved reframing the existing residential structure, designing a new rear horizontal addition, and developing foundation and excavation support systems to accommodate the updated layout and increased structural loads.

The existing building was completely reframed to support a new interior configuration, using a hybrid system of wood joists and structural steel beams to provide long-term stability while preserving architectural flexibility. The project required careful coordination between new and existing framing elements so the renovation could move forward as one cohesive structural system.

Structural Scope

H&Z provided structural engineering for the renovation, helping organize the new and existing structural elements into a practical path for construction.

  • Complete reframing of the existing residential structure.
  • Hybrid wood joist and structural steel beam framing system.
  • New rear horizontal addition integrated with the existing structure.
  • Re-evaluation of lateral and vertical load paths.
  • Reinforced concrete foundation design for the expanded footprint.
  • Underpinning of the existing structure to support construction and final conditions.
  • Temporary support of excavation system for narrow lot constraints.

Foundation and Existing Conditions Strategy

The new horizontal expansion increased the building footprint and foundation loads, requiring a full review of how gravity and lateral forces would move through the renovated structure. H&Z designed a new reinforced concrete foundation system and coordinated underpinning for the existing structure to help maintain stability during and after construction.

Because the site is located in a dense Brooklyn setting with narrow lot constraints and nearby adjacent properties, H&Z also designed a temporary support of excavation system tailored to the site conditions. This helped support the excavation phase while keeping the design aligned with constructability and urban-site limitations.

Engineering Result

The Ditmas Park project highlights H&Z's ability to deliver clear, code-compliant solutions for complex urban renovations involving mixed framing systems, foundation rework and confined construction conditions. The project was completed in close collaboration with the architect and general contractor, with H&Z providing responsive communication and quick turnaround times throughout design and construction support.

The site is currently under construction, and H&Z looks forward to sharing additional updates as the project progresses.

Planning a Major Renovation or Rear Addition?

H&Z supports homeowners, architects and contractors with structural engineering for renovations, additions, foundation work and existing-condition challenges.