A new invention, Exolation, helps energy efficiency

A Street administration initiative to rid city neighborhoods of derelict rowhouses addressed one problem but created another:

Energy-inefficient conditions inside the adjoining homes left standing.

Regardless of how aesthetically unappealing blighted properties are, they help insulate the rowhouses on either side of them. Once those brick blankets are demolished, the properties that remain are harder to keep warm in winter and cool in summer without cranking thermostats or air conditioners.

The end result is often higher energy bills for "people who really can't afford" to pay more to be comfortable, said Fredda Lippes, the city's sustainability manager and also an architect.

Six years ago, she and other city officials contracted Philadelphia University to find a solution. One appears to be just a few safety tests away - and could earn the cash-strapped city some needed income.

Philadelphia University was awarded a patent last month for an exterior insulation invented by three professors. A search for a company to make their "Exolation" is under way. In the interest of creating local green jobs, the city hopes to find a local manufacturer.

With its potential for broad application in residential and commercial construction - especially with federal stimulus dollars pouring into every state for weatherization programs - Exolation stands to be a financial boon for Philadelphia. Under its contract with Philadelphia University, the city is entitled to a portion of any Exolation royalties, Lippes said.

That a Philadelphia problem has led to a local invention is no surprise to Mark Alan Hughes, chief policy adviser to Mayor Nutter and the city's director of sustainability.

"In our city, [invention is] a tradition as old as Ben Franklin," Hughes said. "Need fire insurance? Invent the fire insurance company. Need to make that company more profitable? Invent the lightning rod. Need a way to bring the benefits of insulation to rowhouses that have lost a neighbor? Invent Exolation."

The product consists of layers of insulating foam (for thermal protection), high-density foam (to absorb impact), fabric (to prevent penetration of sharp objects), and a latex-stucco finish. The idea is to produce it in 2-by-4-foot panels that will be affixed to a wall with a foaming adhesive. In two tests, crews of three were able to cover an entire rowhouse wall in four hours or less, said Chris Pastore, an engineering professor at Philadelphia University and one of the trio who invented Exolation.

The other two are Robert Fleming, an associate professor in architecture at Philadelphia University, and Tom Twardowski, who is now a visiting professor of chemical engineering at Widener University.

Michelle Knapik was Philadelphia's director of energy policy when Street's Neighborhood Transformation Initiative exposed the insulation problem done by demolition to surviving homes.

She said Philadelphia University's help was enlisted after the city determined that existing exterior-wrap products were too expensive and not sufficiently durable. Though now at the Geraldine R. Dodge Foundation in Morristown, N.J., where she directs the environment program, Knapik is still a cheerleader for Exolation and has been spreading the word about it.

"You look at all the urban centers where this can have impact," she said in an interview last week. "I'm thinking Camden, Trenton, and Newark, in particular."

Pastore is even thinking of applications outside the city - far outside. He said he envisions Exolation on the exteriors of the cinderblock mushroom growth sheds ubiquitous throughout southwestern Chester County.

To Fleming, the effectiveness of any exterior product that would help improve the energy efficiency of a Philadelphia rowhouse would "be diminished" if the product did not work aesthetically. Thus, he worked to ensure that Exolation would be an acceptable canvas for the city's mural artists. He thinks it is.

"Artists can preprint each panel with a segment of an overall image that they wish to display on the wall," he said. "In the end, the community receives a large-scale work of art and the homeowner receives a warmer house."

At the Energy Coordinating Agency, a Philadelphia-based nonprofit involved in city weatherization efforts, executive director Liz Robinson said she would like to use Exolation in a pilot program that would test a variety of technologies to achieve a "zero-energy rowhome." That is a home that is able to return to the power grid as much energy as it uses through a variety of energy-efficient techniques and renewable-energy systems.