As a former director of industrial and labor relations for two major firms (CIBA-Geigy Corp. and Engelhardt Industries) and later the Macke Co.'s man for personnel here, Gilbert H. Schultz is not your everyday psychology major out of Rutgers. That's because he's now a home builder.

"About three years ago, I was at a UGF (United Givers Fund) dinner and got to talking to some area executives and the topic turned to housing," Schultz said. "To be frank, most of their comments seemed to center on the difficulty of getting a well-built house with quality materials, regardless of the price range. Somehow, that set me to thinking. And maybe I was ready for a change. Anyway, I started reading books on home building, making layouts and floor plans. And more than a year later I finished this house."

"This house" is a somewhat unpretentious, but large L-shaped rancher with 4,000 square feet of living space and a three-and-one-half car garage on the first floor. The one-acre site, in the Ashton Pond area of northeastern Montgomery County is shady with trees.

But, not unlike taking a bite of an apple to determine if it's sweet and juicy or dry and mealy, one has to see the inside of the Schultz house to appreciate the workmanship and materials.

The double-door entry leads into a flagstone foyer with a paneled guest closet and a library-den (now used as an office by Schultz) with walnut paneling. On the right is the private, or sleeping, area with three bedrooms. The master suite is finished in a butternut wood in random widths and pieces to achieve a custom look. Schultz made the selection with considerable care. The walnut and butternut paneling are both Townsend pre-finished tongue-groove boards that can be washed with soap and water.

Closet space abounds in all bedrooms and the dressing table is Corian marble. The master bath has both tub and shower. Walls are mostly Corian.

The 24-by-16 living room is formal and the 17-by-14 dining room has walnut wainscoting, plus Sanitex wallpaper. The 25-by-20 family room with solid cedar beams, rails and posts, is open to the wide hallway and is adjacent to the finely appointed kitchen and breakfast area. All the solid oak Rutt-Williams kitchen cabinets are on ball-bearing hinges and close automatically. Working lazy susan storage bins are in the kitchen and pantry.

The Schultz sons, 13 and 17, are encouraged to enter from play or work via back door to a hallway where a closet is the first stop and then a small full bath.

"The boys and I can come in dirty, undress, toss our clothes across the hall to the laundry, take a shower and then go to our bedrooms inside a wrap-around towel, if there are no guests in the house," Schultz said.

Throughout the house the ceilings are a thick insulating material with a brush-effect finish. And all the walls have extra-thick insulation.

There's a parallel electrical circuit to serve the many appliances. A 1,000-gallon fuel tank provides for oil for two furnaces. The house has two-zone air conditioning, plus continuously circulating hot water. The unfinished basement is as huge as the full first floor and has a fireplace too.

That's just a quick look at the house that Schultz built to sell for about $250,000. But the market was unready for his effort in 1974 so he moved his family into it from a nearby dwelling. Now Gerrie Sims of Cortland Realty, a friend of Schultz and his wife, is offering the house at a lower price on the multiple listings.

For a fellow who built his first house for himself in New Jersey and then built another for his mother-in-law in Massachusetts, Schultz is still relatively inexperienced. He has one other house, much smaller, under way for a friend. But he bases his approach on investigating the quality of the materials, craftsmanship and products that he puts into a dwelling.

"You could also say that I'm a born-again Christian. So is my wife and our sales agent, too. Maybe that's one reason why I see what I am doing in terms of something more than creating a house. I'd like to do smaller, lower price houses - but with top quality materials," he said.

"But what is more important than the houses themselves would be an opportunity to create a small workforce among older persons with skills to pass along and young people who want to learn on the job. This may sound somewhat far-fetched or evangelistic. But I am personally convinced that Americans need to find more service and satisfaction in their work by enriching the status of working with our hands."

Meanwhile, Schultz has a house to be sold so he can move on to another project.

His best reference on the house at 17521 Shenandoah Ct., off upper New Hampshire Avenue and just this side of Ashton, may be veteran appraiaser Allan B. Elliott, who sent along a note urging a look at the house.

"The owner-builder has succeeded in creating an extraordinary residence. It is as nearly maintenance-free and costless (relatively inexpensive) to operate as any property which I have seen or heard of."

At any rate, the husky, fortyish Schultz put a lot of himself into the house. And it shows it. CAPTION: Picture 1, This L-shaped rambler of builder Gilbert H. Schultz, in the Ashton Pond area of Montgomery County, has 4,000 square feet of living space on the first floor. The house is currently on the market for $205,000. By James Purcell - The Washington Post; Picture 2, The kitchen at the Schultz house has 4-foot-square "island."