Removing stucco stains requires a soft-bristle touch

Q. We have enjoyed your column for many years. We're planning to sell our gorgeous "painted lady," a 1884 Victorian, after owning it for 40 years.

We have stuccoed walls (and a landing halfway down) to the cellar bathroom/spa (once the laundry) from the kitchen. It has charm. Its theme has been a descent to Mexico to escape winter's cold.

There are many stains in the stucco surface on the landing. We tried to clean one area with 10 percent bleach in water, but without any result. We're afraid using pure bleach might destroy the stucco.

Our carpenter/painter who has been helping us to prepare the home to sell suggested mixing a white ceiling paint with 50 percent water and coating the landing. I assume a thick coat of paint would fill in the stucco.

Can you send your advice so we can treat the problem?

A. You could try to clean the stains with a solution made of one cup TSP-PF and one quart Clorox bleach in a gallon of water. This is a proportional guideline; you will not need that much solution, so adjust the quantity of the suggested ingredients as needed.

Pour the solution onto the stains and gently scrub them with a soft-bristle brush. Hard brushes could seriously damage the stucco, which is porous.

Rinse as well as you can after protecting the surrounding areas, which could be severely damaged by the solution. (For outside use, TSP-PF can kill vegetation and poison the soil for a long time.)

Another option is to make a solution of equal parts Deck & Patio Cleaner and Oxy-Boost, following the directions from the manufacturer, Ecogeeks. You can buy these products online at www.ecogeeks.com.

There are also commercial stucco cleaners on the market. You may find them in masonry-supply houses.

As always, use eye and skin protection when handling chemicals.

Q. A mold problem exists in an underground room, even though a humidifier is on that empties into a sump pump. French drains also are in place. There are two restrooms, each with a toilet and sink. When heavy rains occur, water seeps onto the floor.

The block walls were covered with plastic sheeting then blue board that has been wallpapered. There is a cellar door once used for coal, but electric heat upstairs replaced the coal heat many years ago.

This is a historic 1852 stone church with a tile roof that sits on level land. Downspouts that were not part of the original building have been removed, but the problem continues.

Can you suggest a way to rectify the issue?

A. I wish you had given me more details about what you refer to as French drains. The term is often erroneously applied to different types of drains.

A French drain is an exterior trench set a few feet away from a building's foundation, with or without a perforated drain pipe on its bottom over a couple of inches of stones. The trench is then filled with stones left exposed to the very top of the trench.

A curtain drain is similar to a French drain, but the stones stop a foot or so below grade. The stones are covered with geotextile fabric and the backfill is completed with a thin layer of coarse sand topped with soil, and shaped with a swale to catch surface water.

Are you referring to interior drains? If so, what do they consist of? In order to attempt to fix the leakage, the first thing to check is the grade around the church. The grade should gently slope away from the building, and a healthy stand of grass or ground cover should be grown to absorb any water that percolates deeply.

Since you have removed the downspouts, I presume you also removed the gutters. You should have masonry units (patio blocks, concrete pavers) set flush with the finish grade at the drip line of the roof to prevent roof water from digging a moat in the soil and getting down to the bottom of the foundation walls, where it will find the weak spot and enter the building.

If there are paved areas around the perimeter of the church, and they slant toward the building, they need to be corrected to shed the water away.

You may also need to replace the sump pump with a greater capacity model, but this can wait until you have taken care of any grade problems. Fixing the grade problem may stop the leakage on its own.

By the way, wallpaper over blue board is not considered to be fireproof unless the wallpaper is rated as such. This is worth looking into for safety reasons.

Blue board is a hydrocarbon and burns with an intense black smoke similar to red oak. This is of great concern to firemen responding to a fire, but also to anyone in the room if a fire develops.

Q. We built our home in 1977. At that time, my wife wanted the bricklayer to finish the mortar joints with rubbed burlap, and they were not "struck" with a mortar tool. The pictures I've sent show deterioration of joints in only some areas of the house. In one area on the north side of the house, near the dryer vent, the joints have eroded away. Here we had a mason come in to repoint them.

I am looking for your opinion as to what might have caused this. The erosion was at least one-half inch deep and it would have just kept flaking off if you were to dig at it. In several other small areas on the other sides of the house, this erosion had to be fixed. It is obvious to me that it would not have been caused by a bad mix of mortar on one or two particular days due to the fact that it is not all in one place. Just above the damaged area the mortar is just as firm as the day the bricks were laid. The mason doing the repair didn't really have an opinion.

The other concern I have is what to do with the gable ends of the house. We utilized barn siding, board and batten attachment, and the barn material was taken from a barn built in 1929.

The siding on the west side of the house weathers quite well and we sprayed a preservative - I believe Thompson's Water Seal - 20 years ago and nothing since. I was just doing painting on the east side, and the barn siding there is quite dry.

Would you suggest treating the siding with anything? Linseed oil would be nice but we would need several hundred gallons! Basically, the siding is still in good shape, but I just wondered if you would suggest treating it with any type of spray material. Thanks in advance.

A. The advantage of struck joints is that the process makes them as waterproof as they can be. Rubbing mortar joints with burlap is attractive, but it leaves the joints somewhat porous. I believe this is what has happened to the failing joints.

Since you mention that this is occurring on the north side of the house, it is likely because this wall doesn't dry as fast as the others after any exposure to water.

The presence of efflorescence also indicates that water penetrated the bricks, probably through the joints, and dissolved some of the salts found in all masonry products. When the water evaporated, the salts were left stranded on the surface of the bricks.

Removing the efflorescence is relatively easy. Brushing it off with a dry stiff-bristle brush should do it. But if needed, the brush can be used wet. Repaired joints should be struck to make them more impervious to water.

The old barn siding gable walls should be treated with either a clear preservative or a penetrating stain.

Thompson's Water Seal is a paraffin-based product that needs to be reapplied yearly, as it is vulnerable to the UV rays of the sun.

My favorite penetrating stain or clear preservative is Amteco TWP. The clear TWP will also need to be reapplied every year or two, while any of the available stains should only need to be reapplied every three to five years.

Because the wood is so dry, you will need to apply at least two coats initially to quench the wood's thirst. Follow Amteco's directions for this initial application.

TWP can be sprayed, but it is also best to follow the spraying with brushing to deepen the penetration. However, this may not be feasible.

TWP is not only a preservative, but also offers UV, insect and mildew protection. Linseed oil would be a very poor choice, as it is mildew's favorite food.

Helpful comments from two readers:

In response to the reader who asked how to make a slippery handicapped-accessible ramp safer, here are two suggestions:

• "Ramps, whether plywood or lumber, can be like glass when moist or wet. I have one of each up in northern Wisconsin and learned about it the hard way (ripped up a knee).

"Our solution was to cover the ramps with rolled roofing material. It works great and can be easily replaced when it becomes worn. It has the same grit as shingles, and lends itself to being stapled in place for a nonslip surface."

• "Regarding handicapped-accessible ramps: I built one using ¾-inch plywood. I bought two 4-by-8-foot ribbed outdoor mats. They seemed to work fine last winter."

• Henri de Marne was a remodeling contractor in Washington, D.C., for many years, and is now a consultant. His book, "About the House," is available at www.upperaccess.com. 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.