Before leveling floors, find out what caused the problem

Q. We would like to level the concrete floors of our second-floor condo. The floor problem is characteristic of the 1870s building. The bedroom slants away from the door and falls 3 inches to the worst spot. Is there a cheaper filler we can use prior to using self-leveling concrete?

A. The drop is significant and indicates there has been some settlement. Since the drop is on the opposite side of the door, I presume the settlement is at an outside wall. The cause of the settlement needs to be investigated. Is it due to some problem with the joist system supporting the concrete or some other cause? Did the settlement take place a long time ago and has been stable since, or is it still going on? This is important to determine before adding weight to the floor, which could only be a temporary fix and aggravate an existing serious condition.

You should have a structural engineer study the situation and recommend a safe solution.

Q. I am sure you have dealt with my problem in a previous column, but I need it to be refreshed.

There is a water stain ring, 6 inches in diameter, on top of my dark, antique side table. Unfortunately, I tried to sand the area to eliminate the stain, and now I also have light wood showing. Can you help?

A. Did the sanding remove the stain or is the light wood around the stain's perimeter?

Since the sanding revealed light-colored wood, it indicates that the dark coloring of your side table is in the finish.

You would never be able to match it, so it is best to strip the entire finish off.

If the water stain is black, and still there after the sanding, try applying full-strength bleach to it. Then apply it to the entire tabletop to bleach the wood evenly.

If the bleach does not remove the stain, try oxalic acid. Buy a small amount of the crystals in a paint store, dissolve them to saturation in very hot water in a glass container (never use metal with oxalic acid, a very caustic chemical) and apply the solution to the entire top as described above.

Allow the solution to work for 20 minutes or so, then neutralize the acid by wiping the entire top with a solution made of a very small amount of ammonia (about one tablespoon) to a quart of water. Wipe the wood dry with a clean white towel and rinse the tabletop again with clean water. Dry it with a clean white towel. Use rubber gloves and skin protection.

Any solution applied to the wood will cause the grain to raise slightly. Sand the tabletop lightly with fine sandpaper. You are now ready to apply a new colored finish of your choice to the top.

Q. I was reading in our paper in December about treatments for artillery fungus. Everything I've read for solutions is about treating vinyl siding. What about painted cedar siding? I tried power-washing but it will chew up the cedar siding. Will Mr. Clean's Magic Eraser or other remedies work on painted surfaces? This only happened on the front of my house above my driveway and my concrete porch. The landscape is terraced with block walls and pine shrubs without any type of mulch. My wife plants flowers in front of the shrubs. Any suggestions you have will be greatly appreciated.

A. If there is no organic mulch in your flower beds, I really question whether you are suffering from artillery fungus, which is a result of the decomposing of most organic mulches, except cypress mulch.

Artillery fungus is active only in the spring and fall when the soil and air temperatures are mild. The spores explode with great force and attach themselves to nearby surfaces, usually light-colored ones.

But just in case it is artillery fungus, here is a repeat of a recent answer to another reader:

This fungus was considered almost impossible to remove without causing damage to the surfaces. Or so I thought, until a reader mentioned he was successful in doing so following a new Penn State Extension Service report that several people have had good luck with Mr. Clean's Magic Eraser. The trick is to wet the spots first and wait several minutes for the packets to soften. That seems to make them easier to "erase." I doubt that Mr. Clean's Magic Eraser will damage your painted siding, which could always be touched up, but it is always best to try any treatment to a small, inconspicuous area first.

Another Pennsylvania reader wrote me that he finds the spots easier to remove after they have frozen solid over the winter. He uses a plastic scraper and has had good luck with it.

Q. My wife and I are regular readers of your columns in the Daily Herald in the Northwest suburbs of Chicago and we enjoy them a great deal.

We have not painted the interior walls of our house in more than 15 years. The walls are wallboard, and some have latex paint on them and some have wallpaper. We intend to have the interior painted in the next several months. However, before I select a painting contractor, I would like to know what preparation I should expect the contractor to do to walls that have not been painted in so long. Also what is the proper preparation to have wallpaper removed and the walls painted?

A. If the painted walls are in good condition, with no peeling, etc., they can be cleaned of all possible dirt and dust accumulation with a damp cloth or sponge, although a simple brushing may be all that is needed.

To remove the wallpaper, one of many wallpaper removers can be used after the wallpaper has been scored with a special tool. Or the wallpaper can be scored and steamed off. Some wallpapers are easy to remove dry.

Any paste residue will also have to be removed by washing the walls with a sponge and warm water before paint can successfully stick to the base surface.

An experienced painting contractor should know all the steps needed to paint the walls and remove wallpaper successfully.

Before making your final selection of a painting contractor, ask each contractor for the names of several customers where they dealt with wallpaper removal and check these references.

Q. Some time ago you recommended a polish for kitchen cabinets. Since I now have new wood cabinets, I would like to take good care of them. I would appreciate it if you could let me know what brand you recommend.

A. The miracle furniture polish I have mentioned, and used, over the years is Milsek, which you can find in a number of retail outlets. If you cannot readily find Milsek in your local stores, go to www.milsek.com, click on Store Locator, then scroll down to find your state to locate a dealer not too far from you. You can also order Milsek online.

Q. I have a fiberglass door that faces west. The door is stained a light oak color and is about 10 years old. I also have a storm door to protect it from our harsh Chicago winters. This past summer I started noticing white marks on it. When I rub them I can feel a gritty substance.

My local hardware store suggested I sand the door with superfine sandpaper and then use a product called Wipe-On Poly. That did no good.

I contacted the local manufacturer who installed the doors. They were of no help in suggesting someone to refinish the door. I have contacted several local painters and not one of them will take on the job. One even said it was too much work!

Is this a job I can tackle myself? If so, how do I go about refinishing it and what products should I use?

If you know of someone I can hire locally please let me know. Any input you have would be greatly appreciated.

A. It is not that difficult a job to do, so I do not understand the reluctance of painters to tackle it. You should be able to handle it yourself.

Before I go into the steps needed to repair your door, you should know that having a storm door over an insulated door on a side that gets a certain amount of sun is a bad idea. I have seen many metal doors in private homes and condo projects that have buckled and become distorted under the heat generated by the sun and trapped between the two doors, especially if they are painted a dark color.

If they have a glass insert, I have seen the plastic retaining the glass become severely distorted and the butyl sealant around the glass melt. In some cases, the glass seal was broken from the heat.

If you can change the storm door glass to a screen panel, this will help a lot in the summer, but winter is still a problem if the door gets several hours of sun exposure.

To repair the finish on your door, strip the damaged existing finish with a citrus-based stripper. Clean the surface thoroughly with acetone (do this when you can do so safely with plenty of ventilation, and wear plastic gloves).

Coat the door with ZAR stain or Old Masters stain, both heavy-bodied, oil-based stains. When the stain has thoroughly cured according to the manufacturer's instructions on the container, apply a clear water-based sealer.

• Henri de Marne was a remodeling contractor in Washington, D.C., for many years, and is now a consultant. His website is www.henridemarne.com. Email questions to henridemarne@gmavt.net, or mail First Aid for the Ailing House, Universal Uclick, 1130 Walnut St., Kansas City, MO 64106.

© 2015, United Feature Syndicate Inc.