This 2,993-sq.-ft, four-bedroom home was nearly three years under construction. The contemporary structure is far more energy efficient than a typical Cincinnati code-built home and was completed just in time for quarantine.
Renan and Sven Menninger’s certificate of occupancy was in the mail just days before the stay-at-home order came down from Ohio Governor DeWine. The couple loves the 270-degree views of the Ohio River and the beauty of Cincinnati. Mornings bring flocks of geese racing by and afternoon showers way off in the distance slowly move across the horizon. They are in tune with the weather — good and bad — from their vantage point atop Mt. Adams. Green space surrounds them on one half and the rooftops of the city on the other.
Renan’s profession as an interior designer and operator of RM Interiors provided an opportunity to showcase their style — sleek interior spaces with minimal interior trim, expansive tile surfaces in bathrooms, and generous amounts of Corian in the kitchen and for the fireplace. Those polished surfaces — all in white and black — contrast with thick carpet underfoot.
The style is untraditional and the approach to design and construction followed suit. The site originally accommodated a single-family home. Now it shares a common wall (insulated concrete form) with the neighboring home still under construction. It meant one less surface treatment.
Creating complicated, sustainable architecture
Contractor/builder, Jim Bronzie is an expert in building homes with complicated architectural features and the cantilevered staircase was a supreme challenge. Inviting staircases, such as this one, found in sustainable buildings that encourage taking the stairs are called “irresistible stairs.” Renan says architect Chad Puckett with Fold and Form was a great listener for their exploration of minimalist possibilities.
Since 2002, the city of Cincinnati has granted a 10-year tax abatement on certain structures. In 2007, the city added an additional five years to the tax abatement for those receiving LEED Silver Certification and higher. The current incentives are that owners must achieve LEED Certified and Visitable to receive a tax break on the first $275,000 of the structure’s value for an additional two years. An additional five years is available for LEED Silver $400,000, LEED Gold $562,000, and there is no maximum if you achieve LEED Platinum. Because of the tax abatement, nearly every new home in Cincinnati is LEED Certified and builders have become quite familiar with how to do it cost effectively.
The LEED for Homes Rating System provides a basis for quantifying the benefits of green homes, thereby facilitating the widespread construction of more sustainable housing. One of the first steps in planning a LEED home is to adjust the certification thresholds based on the material and energy impacts. All else being equal, a large home consumes more materials and energy than a small home over its lifecycle.
LEED compensates for these impacts by adjusting the thresholds for each award level. Thresholds for smaller-than-average homes are lowered, and thresholds for larger-than-average homes are raised. A small home’s threshold for LEED Gold may be 72 points. A 4,500-square-foot home with five bedrooms would be about 85 points. An eight bedroom, 9,570-square-foot home is expected to achieve LEED Platinum with at least 115.5 points. In the end, the homeowner will have a well-built and third-party certified house.
The LEED Certification system is broadly categorized into eight parts that demonstrate measurable environmental benefits: innovation and design process, location and linkages, sustainable sites, water efficiency, energy and atmosphere, materials and resources, and indoor environment quality.
Then an Integrated Project Team typically holds regular meetings to review project status, introduce new team members to the project goals, discuss problems encountered, formulate solutions, review responsibilities, and identify next steps. The Integrated Project Team is formed of individuals and organizations with the necessary capabilities and in various project phases to maximize the opportunities for integrated, cost-effective adoption of green design and construction practices.
The project team and LEED rater for the Menninger’s home, Green Building Consulting, met frequently and early in the design phase to better plan, get pre-approval and do calculations before construction.
Site selection is a very important aspect of sustainable homes. The infill site with existing infrastructure didn’t replace prime farmland, parkland, unique soils, or soils of state significance. Excavated topsoil was reused; runoff was controlled, so it didn’t contaminate storm water sewers or erode hillsides. The home was constructed on a previously developed lot.
Community resources/transit require it to locate close to basic resources such as an arts and entertainment center, bank, convenient store, daycare, fire station, cleaner, library, pharmacy, restaurants, places of worship, and schools.
The Menninger’s home achieved Outstanding Community Resources/Transit because it is within ½ mile of 11 basic resources and ½ mile of 125 transit rides available nearby per weekday. The highly desired urban location encourages walking, physical activity, and time spent outdoors. It’s located within ½ mile of a ¾ acre public open space.
Very high-efficiency water flush and flow fixtures were specified for this home with an average flow rate of 1.5 gallons per minute for bathroom faucets, 1.75 gpm for shower stall, and 1.1 gallons per toilet flush.
A Home Energy Rating System (HERS) analysis verification of the energy efficiency of the home will be performed. This home expects to achieve a very low HERS Index of about 40 which will mean that it is 60% more efficient than a typical home in Cincinnati.
Optimize Energy Performance included very high efficiency geothermal systems, lighting, and hot water distribution designs with desuperheater and air source heat pump water heaters paired with Energy Star appliances. High efficiency LED lighting was part of an advanced lighting package.
Enhanced insulation methods achieved a superior results by using exterior finishes that included a two-inch rigid foam with stucco coating as well as a rain screen over the insulated concrete form foundation walls. ICF walls are a leave-in-place concrete form that includes insulation on both the outside and inside of the foundation walls. It produces an extremely tight home without air leakage or drafts. Exceptional windows were used to achieve three out of three points.
Hot water heating was made more efficient by the compact design of the conventional system, pipe insulation, and efficient on-demand domestic hot water equipment.
The choice of building materials is important for sustainable homebuilding because of the extraction, processing, and transportation they require. Construction and demolition wastes constitute about 40% of the total solid waste stream in the United States.
Framing efficiencies included precut packages and sizing headers for loads, ladder blocking, and drywall clips. Construction waste management planning investigated and documented local diversion and measured it, which resulted in diverting 64% from landfills.
Americans spend an average 90% of their time indoors, where levels of pollutants may run two to five times — and occasionally more than 100 times — higher than outdoors, according to the U.S. Environmental Protection Agency. Many of the pollutants found indoors can cause health reactions in the estimated 17 million Americans who suffer from asthma and 40 million who have allergies, contributing to millions of days absent from school and work.
This home reduces occupant exposure to indoor pollutants by ventilating with outdoor air. It also has an energy recovery ventilation system, which recovers the heating or cooling depending on the season from the home’s exhaust air.
There is appropriate distribution of HVAC in the home to improve thermal comfort and energy performance. A typical home which has improved the distribution of space heating and cooling includes a limited pressure differential between closed rooms and adjacent spaces. High performance MERV 13 filters were installed.
This is a residence with very high qualifications for a green home. Congratulations, Renan and Sven, for achieving such an outstanding example of sustainability and beauty.
If you would like to tour some LEED homes in Cincinnati, we suggest joining the local USGBC Chapter and attend their home tours and meetings.
Learn more about every aspect of the Menninger Residence LEED for Homes points at
https://green-cincinnati.com/their-new-leed-platinum-home-was-a-blast-to-quarantine-in/
Chuck Lohre is a SMPS-CPSM; LEED AP-ID +C and editor of Green Cincinnati Education Advocacy, which helps promote Green Building and sustainability in the Tri-State and provide the public with the resources needed to advocate for the U.S Green Building Council’s LEED Certification process and measurable environmental benefits for all species. He can be contacted at [email protected] or 513-260-9025.