Garrett Churchill, Inc., a landscape company serving the Philadelphia region since 1999, designed and installed the Gil Rosenthal Garden of Peace at the Samuel A. Green House, Elkins Park, Penn. Managed by Federation Housing, Samuel A. Green is a low-income housing tax credit building with 84 one-bedroom apartments for the elderly. The garden offers residents and neighbors a green space where they enjoy the shade, foliage and flowers provided by seven shade trees, three flowering trees, 120 shrubs, and 150 perennials included in the design. Four paths lead to a central circular patio with wood bench seating. The patio's centerpiece is a recirculating water feature installed in core-drilled slabs of granite, one of the reclaimed architectural elements Garrett Churchill saved and used in the project.

An old mansion had occupied the site. Federation Housing hoped to renovate it and incorporate it into their facility plan, adjacent to the new apartments. The cost proved to be prohibitive for the non-profit organization. The town approved demolition "?u if the site would be maintained as a park-like green space.

The demolition created a challenge for Garrett Churchill.

"We had to remove a lot of debris, and the soil was in poor condition," said Andy Sykes, CLP, PCH, owner, Garrett Churchill, Inc. "We supplemented the soil with compost and organic fertilizer to increase nutrient and water uptake."

The new apartment building took up all allowed impervious space, so no additional impervious surface areas were permitted within the garden. Finding the right permeable material for the pathways and patio, and meeting requirements to retain stormwater on site, presented difficult problems.

"The average age of Samuel A. Green residents is 80. To get out and enjoy the garden, they need a solid, stable, non-slip surface that is easy to navigate with walkers and wheelchairs. That ruled out gravel," said Sykes. "The paving material also had to have more porosity than permeable pavers. Otherwise, we would have been forced to install additional stormwater retention features at grade, adding costs and detracting from the landscape."

Sykes considered Porous Pave XL, a highly porous and durable pour-in-place paving material made from 50 percent recycled rubber chips and 50 percent kiln-dried aggregate mixed with a liquid binder, as a possible solution. He had completed training at Aquarius Supply, Norristown, Penn., to become a certified installer but had not yet had the opportunity to use it.

"With 27 percent void space, the material infiltrates more stormwater than permeable pavers," said Sykes. "It forms one continuous, consistent, solid rock-rubber permeable surface, and the rubber content gives it good traction while making it freeze- and frost-heave resistant to eliminate the risks of heaving and cracking."

Sykes and a five-man crew installed a total of 1,650 square feet of permeable walkways and patio. As the first step, they put down and compacted a four-inch base of crushed aggregate. Then they batch mixed the granite rock and rubber chips with the binder in a portable mortar mixer. Every 50-lb bag of rock plus a 50-lb. bag of rubber, mixed with five quarts of binder, yielded 16 square feet of material for installation at a 1-1/2-inch depth. Sykes advises careful measurement of the binder so the exact same amount is used in each batch.

"It was easy to install and finish with bullfloats and trowels," said Sykes. "I already specified it for another job." "The garden is a place of beauty and peace, and the pavement makes it accessible and safe," said Jane Lahage, NAHP-e, director of operations, Federation Housing, Inc. "The color and texture of the material complements the building and blends with the landscape created by Garrett Churchill."