The best remodeling work on old houses almost invariably involves preserving some original elements, restoring others, and identifying how the new work can augment the old.

How do you, as a homeowner, translate these various approaches into action? I recommend you begin by establishing what you won’t be changing. The following should probably be on your preservation list.

The Floor Plan. In older houses, the flow between the principal living spaces is usually quite logical. The interrelationship between the main entrance, the parlor, the kitchen, and the secondary entrance typically is practical and workable. In some homes, later additions changed the patterns of use (often confusing rather than clarifying things). If possible, retain the floor plan at least in the original portion of the house. In some cases, that may even mean restoring elements removed by previous remodelers.  For example, in the early seventies, no one wanted a dining room, so the trend was to open them up to adjoining food preparation areas in order to create “country kitchens” or other multiple-use spaces in an open plan. Today the dining room is back. At first, an older floor plan may not seem flexible enough to allow for your planned renovations and a wholesale rearrangement may seem necessary. Try looking again.

Staircases. As the cost of quality craftsmanship has soared, the quality and character of the typical staircase have plummeted. If your stairway(s) have original balusters, rails, and newel posts, restore them. Strip them if they’re of hardwoods or so coated with paint that turnings, panels, or other details are no longer crisp. Find ways to stabilize them (if necessary) that don’t detract from their appearance. Badly worn treads can usually be replaced without too much difficulty, but be sure the details are restored, too, such as the nosing returns (that’s where the rounded edge continues around the open end of the tread) New balusters to replace broken or missing ones can be milled surprisingly inexpensively if you shop around. Staircases are key design elements in a house, and well worth extra dollars to conserve and restore them.

 Woodwork. Up until the years after World War II, moldings remained important design elements even in unassuming houses. Baseboards and casings around the windows and doors were made of wide stock, often with applied moldings to add shadow lines and a bolder, three-dimensional effect. Particularly in the late nineteenth century, cornices were heavy and dramatic. Save all that you can of the original woodwork, including any early paneling, built-in casework, spindle work, and other decorative wood treatments. Think of such wooden elements as worthy of restoration, but also as a source of inspiration. If your plan involves new elements such as windows, doors, or cabinets, try to replicate existing details. Using existing quality work as a source for new detailing will help give the new space a feeling that it is of-a-piece with the existing house.

Plaster Surfaces. Save original plaster where possible. New drywall lacks the strength, durability, soundproofing, and character of traditional plaster. Many techniques have been developed to preserve old plaster walls and ceilings, including special plaster washers that can reattach and stabilize loose and cracking plaster. When an existing partition is to remain in place, try to retain its plaster surface.