Q: I am considering using rubber or PVC tile for my garage floor. In a column last year, you mentioned several brands.

Several of those have the “mushroom” style tabs, and I think that these would provide a pretty tight fit.

My question is about any water or moisture that may get underneath the tiles. If some water or moisture (snow or rain dripping from a car) does get underneath the tile, does this become a problem for the concrete below the tile?

Also, it’s a two-car garage, and there is a seam between the two concrete slabs. If tile is used, is it better to cover this or leave it exposed?

I am a big fan of your columns and have learned a great deal from reading them. — via email

A: You raise an interesting question, and I do not have a perfect answer for you. Concrete garage floors are usually hard-troweled. Therefore, they are not very porous, which would allow water to collect below the tiles. What would happen over time is hard to predict. Mold may develop, but unless the concrete slab is of poor quality, moisture should not cause any damage even if it freezes.

Garage flooring in rolls may be the best option, as there are few seams. The seam in the two pours of your slab can be bridged by the roll flooring.

Some rubber flooring rolls are made of recycled auto tires — a very durable flooring that is moisture- and mold-resistant.

You may want to check this type of flooring on www.rubberflooringexperts.com.

Q: We live in the northwest suburbs of Chicago. In September 2013, we had 875 square feet of bamboo flooring installed over concrete in our condo. The flooring was acclimated and laid over padding.

The following winter was very frigid, and the floors shrunk over a quarter-inch along the outer walls. We were told this was normal with bamboo and low humidity. During the summer of 2014, the floor did not expand back to its original installation. Recently, we had the gaps filled in and now the floor has extreme buckling. I am now told there is too much humidity. How can I find a solution to correct this buckling? It is so bad that it is hazardous to walk on. — Illinois, via email

A: It’s too bad you had the gaps on the outer walls filled. Wood flooring needs room for expansion and contraction.

If you have no baseboards, a better solution would have been to install some, and if you do have baseboards, a shoe mold could have been applied next to them to cover the gap, still allowing the eventual expansion of the flooring, which you have recently experienced.

I suggest that you contact the firm that installed the flooring, have them remove the “fillers,” and see what else they can do to get rid of the buckling.

Depending on how severe the buckling is, it may be possible to dry the flooring by using large-volume fans and dehumidifiers.

If not, ask them what they suggest to repair the damage. It also may be possible to trim the buckled boards. Hopefully, the whole floor would not need to be taken up.

Q: I have just put up gutter guards purchased from Lowe’s and they are working pretty well wherever I have a shingled roof. However, I have a sunroom that has a flat roof and is covered with a rubber roof sheet. Therefore, the guards have no shingles to be put under and then snapped onto the gutter.

I did snap the gutter guards onto the gutter and just had the guard lay on top of the rubber roof. Of course when a good wind came along, they all blew off. I asked at Lowe’s how I could adhere these guards to the rubber — a special cement? Duct tape? They told me that there is such a glue specifically made for rubber, but you have to buy it in a 5-gallon drum. Obviously, I don’t want to do that. Do you have any suggestions as to how I can make the guards stay on without damaging the rubber?

Thanks for your help and all the good advice. — Valencia, Pennsylvania, via email

A: I do not know of any cement that would hold the gutter guards in place, and duct tape would certainly not work. It would soon deteriorate.

Flat roofs covered with synthetic rubber roofing have a metal drip edge on all edges that terminates the roof where it does not connect with another building element.

I am not familiar with the type of gutter guard you bought. Lowe’s seems to sell several types that are of similar profile.

Can the roof side of the gutter guard be tucked under the drip edge? This is what I had to do on a job. It required ripping pieces of pressure-treated wood set on top of the gutter straps to snug the gutter guards below the projecting edge of the drip edge. A bead of polyurethane caulking applied where the drip edge and the gutter guard connected secured the installation.

Q: I am hopeful you can tell me the best thing to do here to stop moisture from damaging a foundation wall.

I have enclosed pictures from the outside, too. I thought extending the eave would solve the problem, but it dawned on me that if that’s where the water came from, the top of the wall would be damaged and not the bottom.

Is this correct? Is it possible there is an underground stream causing the problem?

I would appreciate any help you can give me. — via email

A: The exterior photos you sent tell me that you may have several problems.

I see a downspout that appears to be connected to an underground pipe (foliage hides the place where the downspout enters the ground).

It is possible that there is either a blockage in the underground pipe and that, when it rains, water runs out of the pipe and soaks the ground next to the foundation wall, or that there is a break in the pipe, possibly caused by ice.

In that same area, I also see some soil on a sunken concrete slab, which tells me that water has accumulated against the foundation.

In another photo showing a larger area of the same wall, I see what looks like flat or slightly negative (leaning toward the foundation) bare soil.

I would recommend that you check the underground drainpipe. If you do know where its outlet is, make sure it is open and that water flows out freely. If you determine that the pipe is at fault and you cannot rectify the problem, change the discharge to aboveground with a splashblock.

Tape black plastic to the block foundation and add soil against the plastic to obtain a gentle slope away. Cut off the excess plastic. Plant a heavy grass or ground cover on the new grade.

Q: I love your column in the Daily Herald and make a point to read it every week.

I am looking into replacing our old single-pane patio door and am confused by the many material options. Is vinyl-covered wood or fiberglass preferable in my area (northwest suburbs of Chicago) for energy efficiency? What about durability? I have two medium-sized dogs who do jump on the door when they see a critter outside.

I’d like to get a double pane slider with interior wood grilles (stained inside and white outside, possibly). Which of the many manufacturers makes the best-quality doors?

I know I’m asking a lot of questions, but there seem to be so many options and I want to make a wise choice, especially since I know this will be an expensive project between the door itself and having it professionally installed. — Illinois, via email

A: Fiberglass doors are a good choice. I can’t answer the question about dog damage resistance.

Marvin’s Ultrex offers two types of fiberglass doors: All Ultrex, a solid fiberglass door, and Wood-Ultrex, fiberglass outside and wood inside.

The All Ultrex comes in several colors, as does the outside of the Wood-Ultrex. However, the inside wood of the Wood-Ultrex can be factory-finished or left unfinished for painting.

Marvin products are of high quality, and Marvin’s service has been tops, in my experience. We installed Wood-Ultrex windows and a sliding door in our house, and have found them to be very satisfactory.

In the All Ultrex line, the grilles are between the two panes of glass. They are not wood. The Wood-Ultrex series has the option of having wood lites (grilles) outside the glazing on the interior side of the room. See a Marvin dealer for the various choices.

Marvin windows and doors are sold by building-supply houses and by Marvin dealers, the latter offering installation by their own crews, as far as I have experienced.

Andersen doors are another choice. They are made of wood with a Perma-Shield vinyl covering. They offer several choices of finishes. Andersen products are found in building-supply stores and at Home Depot. I have heard and read varied reports on the quality of the installers Home Depot provides.

Big-box stores generally sub out installations of the products they sell; this is where the quality varies.

Pella is another nationally distributed brand, but I have not recommended Pella products for years because of a number of bad experiences reported to me by readers of this column, and by homeowners who retained me to handle their trouble with Pella. Pella refused to address their claims, always placing the blame on the installation.

Pella products were of excellent quality in the ‘50s and ‘60s. They were the top of the field then, and we installed many of them in those days, but they seem to have fallen on bad times. I do not know if their quality issues have been adequately addressed since my involvement in those cases, or if their service policy has also greatly improved.

I would always recommend choosing a product of high quality, backed up by solid, reliable service. A dealer who has its own crews offers the advantage of a controlled process and one place to address any issues that may arise.

However, there are many contractors who can very competently install windows and doors. It depends on the experience and dependability of the contractor.

Henri de Marne’s book, “About the House,” is available at www.upperaccess.com and in bookstores. His website is www.henridemarne.com. Readers can send questions to Henri de Marne’s email address at henridemarne@gmavt.net, or to First Aid for the Ailing House, Universal Uclick, 1130 Walnut St., Kansas City, MO 64106.