We have engineering experience across a broad range of light commercial construction projects, from new buildings developed using Building Information Modeling (BIM) and sophisticated Building Automation Systems, to very old structures that were built using historic building codes and pneumatic controls. Our goal is to help you achieve your goals in a cost effective and safe manner through innovative solutions.

Below are some of the structural and mechanical planning, design, and construction phase consulting services we offer for commercial buildings.


HVAC Systems

  • Sizing, specification, and control of equipment
  • Duct sizing and layout – rigid, flexible, hazardous, grease, underground
  • Pipe sizing and layout – hot and chilled water, glycol, natural gas, radiant, snow melt, geothermal
  • Energy planning, guidance, compliance – COMCHECK
  • Complete mechanical designs for projects under 25,000 square feet 
  • Updating and integrating instrumentation, controls and automation systems
  • Upgrade, retrofit, and modification of existing systems

According to the US Department of Energy, buildings consume more than 50% of America’s energy on a daily basis. Buildings more than 5 years old, both public and private, make up the majority of energy consumption. Evaluating a building as it stands and providing recommendations to reduce fossil fuel energy consumption is a passion of Sisu Engineering.

We have experience across a wide range of occupancies and project types including laboratories, retail, hospitality, healthcare, multi-family residential, and academic.



Structural Systems

  • Building code compliance reviews
  • Modification to existing structures
  • Wood, steel and concrete structures
  • Concrete footings and slabs
  • Pile foundations
  • Evaluation of occupancy type and load changes
  • Historic buildings and building codes

Loading requirements change when building occupancy or use changes. This may require modifications to the existing structural systems to support the new load. Safety of the building occupants under the new load is our main concern.

Supporting Infrastructure

  • Retaining walls
  • Access road bridges and culverts
  • Slabs on grade
  • Piping modifications

Buildings cannot stand alone – they rely on supporting infrastructure to function. We have engineering expertise in a wide range of infrastructure systems to support your building project.

Commissioning and Retro-Cx 

  • Development of Owners Project Requirements
  • Development of Commissioning (Cx) Plan
  • Existing equipment evaluation and Retro-Cx Plan
  • Contract document and calculation review
  • Pre-functional, functional, integrated testing plan and checklist development
  • 10 month electronic occupant and operator survey

We off an array of remote and on-site services to simplify to Cx process. We develop plans, and commissioning documentation to assist contractors and owners. Every project receives procedures tailored to meet its needs so your systems operate at their peak efficiency when the process is finished. Contact us to see how we can help you streamline the Cx or Retro-Cx process.