We've figured out how to build a record low energy consuming multi-family building at no extra cost.

What You Need to Know


The building, located at 1885 Lexington Avenue, NY, NY, is a seven story mixed use building comprised of 29 coop apartments and 3,500 SF of retail space.

Other Benefits:

The structural wall system/envelope was created using an insulated concrete form (ICF) system. The air and thermal barrier created with the system resulted in a record breaking decrease in energy consumption for space heating and cooling.

Maintenance Requirements:

The ICF wall system requires zero maintenance.

Efficiency or Sustainability Improvements:

The building was required by NYC regulatory bodies to provide extra soundproofing at the windows. This was achieved via the use of triple glazed windows. The natural gas fired boilers are of a "standard" efficiency (85%), but they are located in a boiler room at the roof and are direct vented.

My Motivation:

Our goal is always to produce AT NO EXTRA COST affordable housing that consumes the smallest amount of energy and water to operate. This building was only occupied in 2012, so it has not been through a full heating season with full occupancy yet. The total heating cost for a typical apartment in this building is anticipated to be less than $200 for an entire year (based upon the actual results seen from a similar building that was completed and occupied over two years ago - The Andrew, 65-60 Austin Street, Rego Park, NY 11374).


Do a ton of research, plan your systems carefully, and keep things SIMPLE. Avoid envelope systems that have too many components. The more components/layers you use, the more trades you will have involved in building your project. This will ultimately lead to more places for things to get screwed up.

Open House Info:

As this is an occupied coop building, the capacity for tours will be limited. More information about the tours will be posted closer to the date of the actual Open House. For more information, please send your inquires to: steven.bluestone@bluestoneorg.com

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