SOPHIE AND Nick divided the household chores when they married. He was responsible for all outdoor work and she, the indoor. I've always felt that she was shortchanged in this deal, but that's the way they wanted it, and it seems to have worked -- since they're still married after 28 years.

Sometimes the chores overlapped; such as who would water and tend to the indoor houseplants that adorned the windows of their living room and kitchen? Nick was the green thumb in the family, but since Sophie was in charge of inside matters, the spider plants, Wandering Jews and begonias were now her domain.

Remembering to water her new charges before she left for work was the hard part. Some of the more sturdy survived, while others quickly faded from malnutriton. On her way out the door one rainy morning, Sophie discovered to her surprise that one spider plant was springing back to life. She touched the soil. Someone had remembered to water it! Must have been Nick, she thought to herself, how thoughtful.

The next day however, the spiderplant started to droop again. Sophie looked. No, it was not due to lack of water, but too much water. She then saw "who" had been watering her plants. It wasn't Nick at all, but a slow drip-drop from the top of the window sill. Water was seaping in from a leak in the outside brick wall.

This was clearly a job for the outdoor choreman, Sophie decided as she went upstairs to get Nick.

Bricks walls don't leak easily. When they do, it's more often than not due to structural damage in your house, rather than due to faulty brick. The down spouts at the corners of your house may not be functioning properly causing your gutter to overflow or perhaps the caulking around your windows is deteriorating. Or, says Dan Linaugh, manager of the Brick Shoppe in Rockville, the grade on which your house is built may need alteration to reroute the water from your home.

According to Alan Yorkdale, vice president of Engineering and Research at the Brick Institute, "More and more we see condensation building up on walls -- a direct result of this recent obsession to make our homes insulation tight. The humidity created from showering, cooking, etc, can't escape, causing the walls to 'sweat.' Putting in vents help, but not completely."

Before tackling any brick patch-up jobs, talk to a professional contractor or to an architect to find out just what's causing your wall to leak, crack or what have you. Once the root of the major problem is found and repaired, you can go about minor brick work. In addition to leaks, the brick itself might be deteriorating due to age or poor quality. And says a spokesman at Mount Vernon Clay Products in Northeast Washington, "disturbances like Washington's subway blasting have cracked many brick walls in some of the District's older homes."

Minor brick repair, tuck pointing or repointing, can be done by the average homeowner, provided you have the proper equipment and temperament. The savings is well worth your while.

You'll need mortar mix, which can be bought in 20-, 40- and 60-pound bags at most hardware stores. Prices range from $2.89 for a 60-pound bag at Hechingers to $6.66 for an 80-pound bag at Cherrydale's Hardware and Garden Center in Arlington. Two common mortar-mix brands are Homecrete and Sakrete. And, says Ed Decaneva, assistant manager at Ace District Hardware in Southeast Washington, select your mix carefully -- it should match the coloring of your present mortar.

Robert C. Mack, of the American Institute of Architects, agrees. In his "Preservation Briefs" for the Office of Archeology and Historic Preservation, Mack says: "The importance of matching the composition [of mortar] frequently is overlooked, yet this match is necessary if the new and old mortars are to have the same physical characteristics." And he adds "If it is not possible to obtain a proper match through the use of natural materials, it may be necessary to use a mortar pigment" -- particularly with regard to 19th- and 20th-century structures.

Other equipment you'll need:

Something in which to mix the mortar -- a metal wheel barrel, a plastic wash basin, even a wooden box is fine.

A thin chisel ($2 to $3) or screwdriver is helpful to have when removing the old and often loose mortar before application.

A small metal pointed trowel that's no thicker than a butter knife should be used to apply the mortar. Linaugh of the Brick Shoppe suggests 3/8 to 1/2 inch at most. Trowels range in price from poor quality ones at 89 cents to stronger hand-made ones for professional use at $30. (The $2 variety will do fine.)

A tool known as a plasterer's hawk -- a flat plate, measuring 8- to 10-inches square, with a handle, is a handy tool, but not absolutely necessary. 1A slab of mortar is put on the hawk, from which you can apply the mortar -- instead of returning to the wheel barrow after each application. Hawks cost between $5 and $10.

And if you're doing any climbing to reach your repairs, you'll need a ladder.

Yorkdale suggests you start by mixing the required amount of mortar or mortar and sand combination with just a little bit of water. Allow the mixture to sit; awhile to get rid of any shrinkage. This procedure is called prehydrating and although it's good for tuck pointing, it's not necessary for brick laying.

While waiting for the mortar to shrink, Yorkdale says "cut, or rake out, the old mortar between the bricks, (called "joints") with a chisel. Cut in 3/4 to 5/8" -- making sure the hole is as square as possible; the mortar will hold better."

"Then," he continues, "moisten the hole and begin pressing in the mortar with the trowel. Keep filling the hole until no more can fit in. When finishing up the joint, maintain the same joint style as the rest of the brick wall -- some joints are flush with the brick, others protrude, while still others are indented."

According to "The Complete Concrete, Masonry and Brick Handbook" by J.T. Adams (ARCO Publishing, Inc., New York), "The best joint from the standpoint of weather-tightness is the concave joint. This joint is made with a special tool after the excess mortar has been removed with the trowel. The tool should be slightly larger than the joint. Force is used to press the mortar tight against the brick on both sides of the mortar joint."

J. T. Adams also mentions a weather joint that is angled to allow water to bounce off the wall's surface. It is "formed by pushing downward on the mortar, with the top edge of the trowel," says Adams.

The simple, but painstaking job of tuck-pointing costs you merely the price of the tools and material involved. The cost for a professional brick layer to repair joints ranges from 22 cents a brick to $12.50 an hour. A spokesman at King's Brick Co., Inc., says the average homeowner is best off economically doing this work themselves.

Another product on the market that is helpful when repairing brick is waterproofer, such as Chemstop and Okon. A water-proofer should not be used as a replacement for mortar, but it can be used in conjunction with it. Applying clear water-proofer solutions will make your brick more resistant to water, says Earle Garner of Every Water Guard Co., Inc., in Rockville, "and won't discolor your brick since it's a clear solution." Another advantage to proofers, says Garner, is that they can stop leaks through cracks in the same way caulking does.

Another product that can be used, but is not as effective, according to Garner, is a water repellent solution that contains silicone. It will repel a certain amount of water, but, says Garner, "water repellers don't have the bridging ability to seal like water proofers do. Water repellents will not prevent leakage in a heavy rainstorm, for example."

John Cunningham, manager of Cherrydale Hardware, suggests that you apply these products to brick when the brick is very dry -- it will absorb more when dry." And he adds, "Be careful about proofers and repellents. They can fix your brick wall cosmetically, but your real problem may still not be solved."

Waterproofers range in price from $14 to $20 per gallon, while water repellents cost between $10 and $14 per gallon. (Some hardware stores carry these solutions in quarts and pints as well.)