What do America’s greenest homes have in common?

From programmable irrigation systems to gardens teeming with native plants, this is how the latest recipients of the LEED Homes Awards pushed the envelope in sustainable design.

Judging multifamily, single-family and affordable housing projects from around the world, the awards from the US Green Building Council recognise homes that reduce their environmental impact and improve residents’ lives.

This year, each of the winning single-family developments achieved a LEED Platinum rating – the highest possible – using several recurring features.

The winners

• Casa Anahuac – San Nicolas de los Garza, Mexico – LEED Platinum (113 points)
• Myers Heckman ­– Cincinnati, Ohio – LEED Platinum (103 points)
• Newman Residence – Chicago, Illinois – LEED Platinum (83 points)

Highlights

Material reuse and recycling

Each of the projects reused or recycled a substantial amount of material. Myers Heckman, a renovation of an 1870 townhouse, added space and new low-carbon features to the existing building. By doing so, it was able to keep the foundation, walls, flooring and interior trim.

The Myers-Heckman Residence in Cincinnati, Ohio

Meanwhile, Casa Anahuac – the first house to receive a LEED Platinum certification in Latin America – underwent a “detailed deconstruction”, which led to 89% of materials being reused, donated or sold. A similar effort allowed the Newman Residence to divert 80% of materials from the landfill.

The Chicago refurbishment also relied on locally sourced materials.

Energy reduction

The Myers Heckman house reduced its energy use 68% by using:

• Rigid insulation on walls
• Robust air sealing
• Roof insulation

In addition, the home has a 9.9kW solar array that takes care of most of its energy needs – despite the building being 100% electric.

Casa Anahuac has 69 PV panels on its south-facing roof, which generates 4,500kWh bimonthly (by comparison, the average US household, for example, uses about 11,000kWh per year).

Recycling water

Both Myers Heckman and Casa Anahuac capture and store rainwater. The former has a 550 gallon cistern buried in the backyard, which harvests rainwater to irrigate plants in the yard – which uses native and adapted plants instead of conventional turf.

The latter harvests rainwater, storing up to 10,000 litres, and treats and reuses greywater. Some of that water is used in a programmable irrigation system that has humidity sensors.

And on that note…

Tech – lots of tech

Unsurprisingly, a lot of efficiency comes from automated systems in the houses. From smart HVAC to occupancy sensors, these tools maximise savings that the structure of the buildings make possible.

Other winners

Alongside the single-home winners, USGBC selected outstanding multifamily and affordable developments and an overall winner. These were:

• Fair Oak Commons – Redwood City, California – LEED Platinum (81.5 points)
• Viamonte at Walnut Creek – Walnut Creek, California – LEED Gold (79 points)
• AMLI Fountain Place – Dallas, Texas – LEED Gold (60 points)
• Vincent’s Village – Nanuet, New York – LEED Gold (66 points)
• Osborn Commons –Sault Ste. Marie, Michigan – LEED Gold (60 points)
• West End Heights – Ithaca, New York – (certification in progress)
• Kaust Villa (overall winner) – Thuwal, Saudi Arabia – LEED Platinum (94 points)