"I'M A TIGHTWAD," said B.K. Wesley Copeland. Every day, he would look at the south-facing front of his house as he left for work and fume. The small windows were uninsulated single-thickness glass, and big sections of the facade were wood panels.

Copeland is on the board of directors for the National Center for Applied Technology and president of the International Science and Technology Institute, so he worries about passive solar heat and insulation.

Chardell Copeland, his wife, a free-lance technical illustrator, wanted more natural light for her work.

And architects Leon Brown and Tom Wright, who designed the original 1955 house -- which wasn't built exactly to their plans -- had always wanted to redo at least the front of the house.

A little more than the budgeted $20,000 and seven months work made all of them happy.

The original brick facade was typical 1955 Cautious Contemporary, with panels of wood siding set into the flat front and windows on the smallish side.

The Copelands bought the house in Chevy Chase about five years ago and though they fussed a bit, managed to survive until one icy night at a party, where they met Brown and Wright -- and found out they had perpetrated the original house. "We didn't supervise the actual building of the original house," Brown said. "And we'd always been unhappy with the changes made in it. We were anxious to have a second chance."

Joseph Pirozzolo of Brown and Wright's office was named project designer, and they set about opening up the house to the south to let in the winter sun. They doubled the south glass area.

The effect of the remodeling is more dramatic than the work was complicated:

a 6-by-16-foot balcony at the landing between second and third story level is now stretched over a bit more than half the front. The balcony is sheltered by a roof overhang.

A trellis begins where the balcony leaves off to continue across the rest of the house and shade the new glass below. The wood panels and the old single-glazed windows on all three floors were replaced with large double insulated glass, and the wall reinsulated.

The job was supposed to take three months, but it took seven, with Pirozzolo acting as mediator between teh Copelands and the contractor, in such matters as the foot-high sill raised in error between the balcony and the landing.

In the daytime, the Copelands find that the half wall of the balcony gives them a great deal of privacy when they sit outside. The house is situated well back from the stret, so they don't have the feeling of being on view.

"At night it's like living in a tree house," said Copeland. In the daytime, the glass acts like a mirror.

The house is set against a hillside, so it has two stories at the back, with the principal floor -- the living and dining rooms -- opening to the garden. The garage and guest bedroom are on the first floor. The master bedroom, and the study are on the third floor (counting from the front).

The study is quite a changed room, now that its south window is almost all glass. A set of wicker furniture -- a desk, a spirally chair and a marvelous half-moon shape plant rack -- from Chardell Copeland's family, makes it seem like an authentic sun room or winter garden. She chose a straw waste paper basket and a straw pencil holder to complement the set. A bright colored durrie rug on the floor, a Globe Werneke glass front bookcase, and a bentwood chair work well with the wicker.

The guest room as well has gained much in cheerfulness from its enlarged window.

The living room opens out onto a neat garden, with an extensive lighting system by Vernon Daniels. "Look at this zucchini," said Copeland, showing one about the size of two baseball bats.

In the living room, the Copelands' have a pleasant collection of African sculpture -- including two great Chief's stools -- collected in his travels. The living room is the next on the Copelands list. "At the moment we think we'll just replace the glass with Thermopane," Chardell Copeland said. t

"The Copeland house," said Tom Wright, "is a good example of how a careful design and a modest expenditure can turn an ordinary house into more efficent, comfortable home."