What not to use in a historic Charleston home

An eighteenth-century house South of Broad has stood through more hurricanes than anyone has counted. The heart pine underfoot has been down a very long time, the plaster behind the paint went up wet by hand over lath, and both have outlasted every owner who ever held the deed. Either can be spoiled in an afternoon by the wrong bottle from under the sink.

Cleaning an old Charleston house is mostly a question of what you keep away from it. Here is the short list, surface by surface.

Heart pine floors: water is the problem

Old-growth heart pine is dense and full of resin, which is a large part of why it is still there. What it does not forgive is water sitting on it. Every seam between two boards is a route down into wood that has spent two centuries drying out, and a wet mop finds all of them.

Damp is fine. Wet is not.

• Wring the mop until it is barely damp, work in sections, and dry behind you with a cloth
• Keep the steam mop for tile. Steam drives hot moisture into old seams and into whatever finish is on top of them
• Skip vinegar. The acid dulls a floor finish over time and the damage is cumulative, so it shows up long after the habit started
• Skip oil soaps and polishes. They leave a film that attracts dust and gets thicker with every application, and stripping it is the first thing a refinisher has to do

Charleston floors also move with the season. Boards tighten in August humidity and open in a dry heated January, so the gaps you can see in winter are the same floor you mopped in summer. Vacuum them out rather than flooding them.

Historic plaster: dust it, do not wash it

Plaster over lath is porous, and it drinks. Water leaves a tidemark that dries darker than the wall around it, and enough of it softens the surface itself. On a wall finished in lime wash or old distemper, a wet cloth takes the finish off and leaves a clean patch that is more obvious than the dirt was.

So plaster gets dusted dry. A vacuum with a soft brush attachment along the top of the wall and the cornice, then a dry microfiber cloth, is the whole procedure.

Anything abrasive is worse than water. Melamine sponges, the white ones sold for scuff marks, are a fine abrasive, and on a soft historic finish they burnish a shiny patch into a flat wall.

Original millwork and painted trim

Deep casings, panelled doors, and a chair rail that has been painted twenty times hold a startling amount of dust along every top edge and in every corner of the moulding. That is the part worth attention, and it is the part a quick pass misses.

Dust first, dry, with a brush or a cloth that will get into the profile. A barely damp cloth afterwards is fine on painted trim. What matters is that the dust comes off before anything wet touches it, because wet dust on a moulding profile becomes a grey line in the shadow of the detail.

Nothing gets sanded or scraped during a cleaning. Paint sold for American homes before 1978 could contain lead, and in a house this old the layers underneath are anybody's guess. Making dust from them is a specialist's job with its own equipment and rules. It is not a task for the person who came to clean your kitchen.

Marble mantels and original brass

A marble mantel or hearth is calcium carbonate, and acid dissolves it. Vinegar, lemon, and most bathroom limescale removers will leave a dull ghost exactly where the drip sat. That is etching rather than staining, so it does not wipe off, and the fix is a stone specialist. Warm water and a soft cloth handle almost everything a mantel actually needs.

Brass is the other one people get wrong, usually with good intentions. The dark, even patina on an original box lock or a set of hinges took a century to arrive, and polish removes it in a minute. It does not come back. If the hardware is lacquered, polish takes the lacquer off in patches and the bare spots then darken unevenly, which looks worse than either state.

Dust the hardware and leave it. Whether to polish a set of original brass is a decision the owner of the house makes once, deliberately, and it is not a cleaning task.

Old glass sits in old putty

The wavy glass in an original sash is thinner than the float glass in a modern window, and it is held in place by putty that hardened decades ago. A razor blade taken to a spot of paint, or hard pressure on a pane while cleaning it, is how a sheet of irreplaceable glass cracks.

Clean the glass gently with a cloth, keep the blade in the drawer, and leave a sash that has been painted shut alone. Forcing one is a repair, not a clean.

Humidity is the constant

Everything above happens against a Lowcountry summer. Marsh air pushes moisture into every porous surface in a downtown house, and the older the construction the more places it finds. Closets on exterior walls, the cool side of a north-facing room, and the seals in a bathroom are where it lands first. There is more on that in our post on coastal humidity and mildew.

Worth saying plainly: our cleaners do not treat mold. A house with a genuine mold problem needs a specialist before any cleaning is useful, and that order does not change because the house is historic.

What to tell us when you book

The single most useful thing you can do for an old house is say what is in it. Your cleaner brings all the standard supplies, and if you would rather a particular product was used on your floors, you can ask for it. If you keep your own vacuum or a specific wax for the heart pine, you can have those used instead. Tell us at booking rather than on the day.

Two more worth mentioning in the same message:

• Which surfaces are original. Where the plaster is historic, where the trim has never been stripped, which mantel is the real one
• Anything small and irreplaceable. Put heirlooms, collectibles, and anything of sentimental value somewhere safe before any cleaner arrives, in the same way you would before a party

Our cleaners also do not perform repairs. A loose baluster, a bit of failing putty, or a hairline crack opening in the plaster all want a trade rather than a cleaning visit, and telling us about them means nobody leans on the thing that is already moving.

Where to start

If the house has not been professionally cleaned in the last 30 days, start with a deep clean. It covers 33 of the 35 tasks on our published 35-point checklist, including the door frames, casings, and baseboards that carry most of the dust in a house full of original trim. It is also how you see what the standard looks like in your own rooms before committing to anything.

After that, rhythm does more for an old house than intensity. Recurring visits keep dust off the mouldings and moisture from settling in, and the same cleaner comes back each time, which means somebody learns your particular floors instead of meeting them cold. Recurring plans save 20% weekly, 15% every other week, and 10% monthly, applied to every visit.

Booking takes about a minute, and there is no long-term contract on the other side of it. The house has waited a couple of centuries. It can wait for the right cloth.