Use friends and family to find reliable contractors

Q. We are currently having a water problem with our porch roof. It’s about 15-by-30 feet with stone parapets on two sides and a gutter on the side opposite the house. We surmise it is constructed of a concrete slab, wood lath and roofing material on the top. We have access to the roof through a door and occasionally use the area. Our problem is water seeping through and wetting the bottom of the concrete slab, which we can see from below. We have had it repaired several times without success, and have decided to have the area repaired again, removing everything down to the slab and replacing with new material. Hopefully the concrete slab is sound and can stay.

We are not sure how to go about locating a good reliable contractor for the job. Could you please offer us some advice in this regard?

A. There may not be a leak through the concrete, but condensation in cold weather. If you can verify that this may be the case, once you have removed everything above the slab, a solution may be to add 2-inch thick XPS rigid insulation on top of the slab over which a rubber roof will be applied. In that case, you cannot put furniture on the porch roof, as it may puncture the rubber roofing.

To locate a reliable contractor in your area, ask your friends and neighbors if they have used a general contractor and been satisfied with the experience. If you have used a licensed electrical contractor or HVAC contractor, and you have great faith in either or both, ask them for recommendations. Often, good subcontractors are a great source of general contractors.

Q. We recently purchased our first home (a 1957 fixer-upper Cape Cod). It has beautiful oak hardwood floors throughout that seem to show no signs of having been treated with polyurethane (or any other sealer). In a few places in the house, when it is not humid out, there are grayish-white liquid damage spots on the floors. When it is humid for a day or more, these spots turn a dark brown/black color and become wet and sticky. Running a dehumidifier in the room seems to dry them back out. My question, since I have been unsuccessful in finding anything that seems to match my situation on the Web, is what could this be and how in the world do I get rid of it? It is in our not-so-immediate plans to refinish the floors, but I do not want to even start that project until I have an understanding of what could be going on. Seems like “locking in” whatever this is would only make matters worse down the road.

A. You are correct; sealing the stains in is not a good idea.

It sounds as if potted plants are responsible for the discoloration. Try this: Lightly sand the stained areas, apply a saturated solution of oxalic acid with a small brush and let it stand overnight. Wipe off the oxalic acid crystals with a clean cloth dampened in white vinegar. If you have achieved some success, but not all you wish, do it again.

Buy oxalic acid crystals in paint stores. Oxalic acid is very caustic, so wear rubber gloves, old clothes and eye protection. To obtain a saturated solution, mix the acid in hot water until some crystals remain in suspension. Use a glass container to mix the solution and do not use metal tools of any kind.

Dispose of the remaining solution ecologically.

Q. We have a really well-built home that needs a little updating. The kitchen has great quality cupboards and Corian countertops that are in very good shape. The problem is the awful white vinyl flooring. I would like to put in a tile floor, but having once done that before in another house, I then had to replace the dishwasher — the countertops had Formica and I cut out a piece to get the dishwasher out. Should I replace the dishwasher before I tile the floor? Do they have a dishwasher that I can put in that will be adjustable to take out when it dies? I do not want have to replace the countertops or raise up the cupboards. Any suggestions?

A. Check to see if your present dishwasher has adjustable legs; most do. If it does, can they be adjusted to allow the dishwasher’s removal? If so, remove it and install a piece of plywood the thickness of the tiles, but keep it slightly shy of the front panel of the dishwasher so you can slip the tiles under the appliance and butt them against the plywood. This will make later removal, if and when needed, very easy.

Q: I live in the Chicago area and will be removing the carpeting and padding (installed directly on the concrete floor) that is currently on my basement floor. My home is about 40 years old. I will be replacing the carpeting with laminate or tile. My question is about manufactured subfloors DRIcore and OvrX.

While I don’t have a problem with water in the basement, I’ve read that these types of subfloors could help with the “musty” damp feeling in the basement.

It appears, though, that the DRIcore and OvrX have different claims for their products.

DRIcore promotes the benefits of the “under floor air flow” of their products, while it seems that OvrX is more about insulation.

Do you have any experience or opinions about these products? Also, if you don’t think much of these products, how do you feel about the new floor being installed directly on the concrete floor?

A. I have no experience with either of these products, but I do have opinions. DRIcore’s claim about its product allowing the concrete to breathe is far-fetched. How can the slab breathe when it is covered by what the company claims is a vapor barrier product? OvrX is an insulating system that seems to make more sense.

But you can insulate the basement floor using full sheets of 1-inch thick XPS covered with plywood sheets held in place with a few power shots (fasteners shot with the appropriate tool) into the concrete. This is what we have and it has worked very well. The finish cost may be considerably less.

Laminate is fine, and so are tiles, but look into engineered flooring as well; you may decide that it is advantageous because it can be refinished if damaged, whereas laminate cannot.

Q. Last September, we replaced the sidewalk and walkways to our house. An Internet search reveals conflicting opinions about whether concrete sealer should be applied. What is your opinion?

Also, a crack developed in one of the panels within two months of putting in the sidewalk (see attached photos). We avoid putting any salt on the sidewalk and the devil’s strip between the street and the sidewalk minimizes, but this does not entirely eliminate the amount of salt from the street. Is this crack a cause for concern and if so, what can we do about it? We approached the contractor about the crack and he responded, “It’s concrete — it just does that.”

A. Isn’t the sidewalk the responsibility of the local government? Usually sidewalks and walkways are not sealed, but there is no reason why they can’t be. It would provide them with some protection from salt damage.

If you opt to do so, consider applying a penetrating sealer instead of a topical one, which would require nearly yearly maintenance.

The crack looks like a drying crack. These cracks occur if the drying of the concrete takes place too fast because it was either not covered with plastic for a few days or a curing compound was not sprayed on it in a timely fashion, or at all.

Your photos also show some damage on the edges of the crack — a few places where the concrete broke off. This can get worse over time. These areas are so small that it may be difficult to repair them, which you can attempt with a product like Top N Bond.

Q. I live in the Pittsburgh area and recently had a stone patio and pressure-treated wood pergola built at my home. I want to wait a year before using any type of stain or sealer on the pergola. My preference is something that will preserve and keep the natural wood color of my pergola. Which products do you recommend for this application? How often does this need to be applied, and is this one-year waiting period before applying the first treatment long enough?

A. There are products on the market that can be applied to pressure-treated wood immediately after installation. Their advantage is that it will keep the wood clean and lock in its natural color, whereas waiting a year may cause the wood to weather to a less-appealing look, develop cracks and even cup, if it was not properly screwed down.

If you prefer to wait, a year is sufficient as long as the pergola is not under deep shade and subjected to very wet weather.

Products to consider are Wolman brand sealers and Amteco TWP, which is very good and offers clear sealers, www.amteco.com. Your local paint store may carry different brands.

Clear coatings need to be reapplied yearly, whereas tinted coatings can last several years.

Ÿ Henri de Marne was a remodeling contractor in Washington, D.C., for many years, and is now a consultant. Write to him in care of the Daily Herald, P.O. Box 280, Arlington Heights, IL 60006, or via email at henridemarne@gmavt.net.

© 2012, United Feature Syndicate Inc.