How do you turn a 100-year-old Philadelphia row-house into a green house? Better question: How do you make that row-house green enough to potentially forego HVAC half of the year?

David Krupp

David Krupp

With lots of love, forethought and green savoir faire, says David Krupp, a Philadelphia based LEED Accredited Professional (LEED AP) Realtor and developer. Krupp is selling what he and his architectural designer-owner clients hope will be the first LEED Platinum residence in Philly’s Center City neighborhood, a converted row home at 1500 Montrose Street.

“As it stands, there are no LEED-Platinum certified homes in the Center City area,” Krupp says. “Right now, we’re ‘racing’ with another one.”

When husband and wife duo Christopher and Emily Stromberg – founders of Southern Liberties sustainable design studio in Philly bought the 900-square-foot classic more than three years ago, it was their first personal green-build project. They’d done other such jobs for clients. The couple’s goal was to green it to the max, then sell it. Specifically, the Strombergs wanted to create a luxe living space, doubling its original size, dovetailing modern with quasi-historic (100 years isn’t exactly “historic” in the three-centuries-old City of Brotherly Love) and adding a third level with an efficient, open stairwell. The desired outcome: A townhome in a charming old neighborhood ranked at LEED PLatinum, the highest level of the four-tiered U.S. Green Building Council’s certification labels.

Krupp says his research shows that only four LEED-certified houses have sold in Philly over the past year or so, and none have attained Platinum. But the Strombergs hope to receive their Platinum certification – which only 419 residences in the US have achieved – very soon.

The totally renovated home on Montrose Street drew more than 300 people during a four-hour open house in July. Since then, Krupp says, the couple have pretty much wrapped up the project, which has drawn lots of traffic, as well as attention from design and environmental professionals. Now, it’s on the market for $565,000.

“At first, people hear that and think it’s overpriced,” Krupp says. “Then they go there and look around and think it’s under-priced.”

According to the Energy Coordinating Agency, a third-party nonprofit that does energy audits and projections, the renovations will cut energy use by half or more, including the need for seasonal AC and heating. If true, that would help validate the house’s asking price.

So, how, exactly, is it possible to cut HVAC usage that dramatically? Especially in a city like Philly, which has muggy summers and frigid winters?

Krupp explains that within the building’s “envelope” (its containing structure), the Strombergs installed two inches of spray-foam insulation, which serves as an air and moisture barrier (typically, builders use fiberglass, which air and moisture can permeate). Also, the couple placed eight inches of rigid-board insulation between the ceiling and roof. The roof itself is fully vegetated, creating a green barricade that absorbs the sun’s heat and keeps rainwater from draining into the city’s gullies and, ultimately, into its sewage system. The whole-house fan, at the top of the stairwell, sucks heat up and out from the lower levels.

To offset the green roof’s solar absorption in winter, when the house itself needs warming rays, the Strombergs put an oversized window – “almost like a door” – at the top of the stairway, between the green roof and the whole-house fan, so that the heat and light from the sun act as a passive solar unit in winter, traveling down the stairwell, all the way to the basement.

One of the simplest, or least “dynamic” elements in this energy-efficient home, is the solar shade system, which the Strombergs had installed on the roof, facing south.

“They’re these big wood (stationary) awnings that jut out and are built based on computer models that indicate, as the seasons change, how the sun is going to hit the windows during different times of year. That determines how far out the awning should be built,” Krupp says. “So that’s a big element for keeping heat out when you don’t want it and the cold in when you do  – and vice versa. You’re essentially keeping the envelope of the building from changing temperature as much as possible.”

Other energy-efficient designs: “Christopher and Emily have done a lot of things to enhance circulation of the air, without using a central cooling system. They have fans in every room … and they have louvered transoms above every door, so that if the doors are closed, the air can continue to circulate.”

As Krupp and the Strombergs continue showing the property and hosting open houses, they hope to find a buyer who will allow them to actually test their energy-efficiency claims.

“We’re going to track it even after it’s sold,” the Sothebys realtor says. “That’s the goal. We’re hoping the buyer is willing to share that information… ”

If so, the town-home could be a blueprint for the greenification of similar East Coast-style residences. If a classic row-house (typically not the epitome of efficiency) can go uber-green in Philly, then why not others of comparable vintage in the region?

  • For more information on this and another green-built, LEED-seeking residences see the Green City Journal.

Copyright © 2009 Green Right Now | Distributed by Noofangle Media