Mechanical and Architectural Coordination for Energy Efficiency

By Nathan Ogle, AIA, LEED AP of FFA
Villa Montgomery photo gallery

Villa Montgomery, a LEED Gold certified project, is a 58 unit building consisting of 4 stories of residential units and a landscaped courtyard above a podium with a management office, common room, retail space and two levels of parking. The apartments are intended for low-income families and will carry long-term affordability restrictions making them affordable to households earning from 20-50% of the areas’ medium income. The building is on an urban brownfield site, located on a major traffic artery in an area zoned for general commercial use, adjacent to a medium density residential neighborhood and less than half a mile from the downtown district.

We began the design of this project with one goal in mind: energy efficiency and improving the efficiency of the total MEP system. Methods for doing this involved careful evaluation of individual mechanical components, waste reduction, peak demand analysis, usage of renewable energy systems, whole building analysis (e.g. day lighting, glazing, heating and cooling, thermal mass, natural ventilation and programmable controls), and most importantly, understanding of the long-term life cycle economics of the building systems.

The building employs a high performance envelope including a cool roof, insulated windows with low-E glass and formaldehyde-free fiberglass insulation. The building’s mechanical system is an innovative design with individual parts of the building heated and cooled by water source heat pumps, fed by a hydronic loop with efficient evaporative cooling integrated with the mechanical exhaust that is required for the garage.

The interrelationships of these strategies are complex, and careful analysis of their effects on one another is required to determine the best combination of the various choices available. Note, most of the above methods require close collaboration between the architect, the MEP engineers and the owners.

It is important to incorporate these considerations early, as changes are easier to accommodate in the onset stages, whereas changes to design, drawings, specifications and compliance calculations are difficult to make later. It is possible for the mechanical designer to estimate the various relevant loads and climatic effects with reasonable accuracy with only the most basic information about the proposed building.

Also, it is very important to follow-through after construction for commissioning, management and maintenance. Measurement and verification of system performance is key to improvement in future design work, and the political value of a high efficiency building is only increased by the existence of a data set that illustrates the systems are performing as efficiently as intended.

----------------------------------

Article featured in Guidebook to the LEED Certification Process:  For LEED for New Construction, LEED for Core & Shell, and LEED for Commercial Interiors (Wiley Series in Sustainable Design) - Amazon link for the book