On the South Side Flats along 18th Street, eco-friendly townhomes called Riverside Mews stretch toward the Monongahela River.

"The first eight are sold. We've sold one in the next phase, and they've already moved in," said Ernie Sota, the developer.

Diane Bossart, education manager for the Green Building Alliance, said Riverside Mews is eco-friendly for many reasons.

"It's already in an existing neighborhood. The South Side is a very interesting and historic district. You are also close to transportation such as the bus system," and the Light Rail Transit stop at Station Square is not far, either.

Mr. Sota used Energy Star appliances and fixtures, installed programmable thermostats and dual-flush toilets and included high-efficiency insulation in the roofs and walls.

Buyers have signed an agreement for this particular model at 1815 Merriman Way, where the asking price was $480,333. On the first floor is a foyer, an integral two-car garage to the left, a bathroom with a shower to the right and a bedroom. Off the bedroom is an outdoor patio enclosed by a 6-foot-tall fence.

Climb 16 stairs and you'll be on the second floor where there's a combined living room and dining room and large, eat-in kitchen.

Ample, natural light filters through 7-foot-tall transom-style windows and onto bamboo floors in the 15-by-14-foot living room and the dining room, which measures 15 by 11 feet.

The wooden windows have an extruded aluminum exterior that helps them stand up to the elements; on the interior, they are stained for warmth. These energy-efficient windows possess the high quality found in commercial versions, Mr. Sota said. Doors are made of solid-core birch and have commercial grade hardware, he added.

Off the dining room is a kitchen that's 16 by 14 feet with maple cabinets stained in a rich chocolate brown. There's room for a table and two chairs; glass pendant lights illuminate an island. There's also a breakfast bar for two. There are traditional-style cabinets that open from one side; another style of cabinet covered in frosted glass opens upward when you lift a stainless-steel bar. The quartz counter tops "are far more stain resistant than granite," Mr. Sota said, because they are not porous and made of 93 percent recycled material.

A soft chocolate brown floor is made of Corkoleum, which is made from cork, wood chips and linseed oil.

"Everybody thinks it's concrete until you walk on it," said Kathryn Barry, a Realtor with Prudential Preferred Realty.

Climb another staircase to the third floor, where a master suite includes a walk-in closet. In the master bath, there's a glass-enclosed shower, lined in eco-friendly green ceramic tile called Stone Peak, and a skylight.

An especially handsome vanity mirror that is more than 5 feet wide and 4 feet high is lit from behind by two fluorescent strip lights, creating soft, inviting lighting. Below the mirror is a green glass counter top and sleek, stainless-steel wash basins topped with polished chrome Kohler faucets in a contemporary style called oblo.

To conserve water, all toilets installed in the townhomes are dual flush. The far right button on the top of the commode is for liquids; the one on the left is for solids. Down a hall from the master bedroom is a guest bathroom and bedroom.

The home's HVAC systems takes in fresh air and filters it; there are also energy recovery ventilators that remove all of the exhaust air.

From the model's higher levels, you can see a future phase of the development, which will be even closer to the river bank. Also visible are some of the 40,000 earth tone-colored Belgian blocks found during construction and incorporated into a driveway that services six townhomes. The Belgian blocks lend texture to the development and are a nice reminder of the community's early building style.

This particular model offers 2,283 square feet of living space spread over three floors. However, buyers can choose from nine floor plans that range from 1,800 to 2,400 square feet. The townhomes do not have interior load-bearing walls, so the plans are flexible, said Diana Lynn, project manager for Sota Construction Services Inc.

One satisfied buyer is Rick Hawkins. He attended college in Louisiana, lived in Los Angeles and traveled all over the world because of his work as a television writer and producer. Last August, he bought a 3,000-square-feet unit in Riverside Mews on 18th Street.

Mr. Hawkins drove to 10 cities before choosing Pittsburgh.

"It's just a perfectly wonderful city. We have a deck and a sky room. That's where my office is. We walked up here and saw this unobstructed view. I can see a barge on the river, bikes on the bike path, cars on the freeway, helicopters flying to the hospital. Oh, and the train. Where else can you live and see that?"

Most of the layouts, Ms. Lynn said, offer the option of adding a sky room that has 140 or 280 square feet of space. In the first phase, five of the eight townhomes had sky rooms.

Mr. Hawkins, who calls the quality of cultural activities in Pittsburgh "mind-blowing," likes being able to walk to the grocery store, the dry cleaner, the gym and the bicycle path on the river where he walks a 3-month-old puppy and also rides his bicycle.

He liked Riverside Mews because of its green construction.

"All of the materials that were used to build these were either natural, from the area or are composite or biodegradable. The house has been designed with cross ventilation. They are beautifully insulated."

In the development's final phase along the railroad tracks, Mr. Sota plans to build a parklet so residents have more green space.

So far, Mr. Sota has built 14 townhomes; plans call for 48. Phase one consisted of eight townhomes, including this one. An additional six have been built and one has sold.

To see this model, call Kathryn Barry at 412-833-7700, ext. 248.