Basically, brick is durable and long-lived as long as the mortar joints are sound. Brick houses are susceptible to moisture -- more so than wooden framed houses -- but require very little maintenance.

Fewer new houses are built of brick, since the cost is truly exorbitant for anything other than a brick facade. Surprisingly, a brick facade or skirt seems to be the sign of a custom or semi-custom home here in Colorado, and whole crops of new houses are thinly sheathed in brick (or sometimes "fake" brick). I'm lucky enough to have a full 15" thick double-brick-with-airspace wall: fine rubbed brick with tiny butter joints for the exterior, and larger rough brick for the interior of the wall. The airspace between is for insulation.

• Don't assume that old mortar needs to be replaced - don't repoint or tuckpoint unless you really need to. Old mortar is usually of a higher lime content (hence the term lime-mortar) than the newer replacement mortar you are likely to find to repoint, and the high portland cement content of new mortar can damage old walls beyond repair.

• Don't seal bricks with a water repellent (i.e., water seal) - it can mean that any moisture that is already in the brick stays in the brick, and interior moisture may not be able to escape. Remember that moisture is the bane of any brick structure, and allowing the bricks to breathe is important.

• Don't use hydrochloric acid (muriatic acid) to clean brick, it can cause discoloration or mottling that is permanent. See some hints below on how to clean discolored bricks.

• Don't clean limestone or marble with an acidic cleaner, it will discolor the stone.

• NEVER sandblast old brick! Sandblasting can damage the hard surface of fired brick and open the bricks up to water damage. Not to mention that fact that it can turn beautifully rubbed facing brick into dented, pitted clinkers, and can blast out softened mortar joints. Sandblasting can irretrievably ruin good buildings. Yes, I know that you've seen building sandblasted and they've been just fine, but do you want the wonderful turn-of-the-century house you just bought to be the example that crumbles away? I wouldn't. Don't do it.

  That said, there are alternatives to sand-blasting that could be used if the brick is heavily soiled or stained. Some other options include rice-hulls, styrofoam balls, nutshells, etc. All of these options are easier on brick, althougn still risky. They require far less pressure, and may be safer. Still, the only surface really suited to sandblasting is metalwork.

• Never use expansion joints in historic masonry - they can pulverize brick and ruin mortar joints. Many old brick exterior walls are built with wooden beams (ledger boards) embedded in the brick that are used to attach porch roofs or other exterior structures. Inside, we have made do with picture rails and carefully pre-drilled screws when we absolutely have to. For the most part, anything hung in our house is hung on a screw or nail that was already there! Crown City Hardware and other mail order vendors sell reproduction hooks that are used with picture rails.

However, some older brick houses were meant to be painted. They are constructed of rougher bricks, or seconds, and were designed to be painted to seal them from the elements. Often they were whitewashed, or painted with fanciful colors to mimic stone work.