Attack rust spots on metal with sanding, primer and paint

Q. We have a white metal garage door that's about 20 years old. There are some rust spots showing on it and we've tried everything to remove it without success.

We also have a sink with rust spots, which will not come off. Would you please let us know how we can remove this rust?

A. Try lightly sanding the rust spots on the garage door until all signs of rust are gone. Clean the entire door with a car washing or similar brush and detergent.

Prime the rusty area with a metal primer, such as Rust-Oleum, and paint the door with your choice of an acrylic latex for exterior use using a synthetic bristle brush.

You have not said what type of sink you have; is it the kitchen, bathroom or laundry room sink? Is it acrylic, porcelain enamel or something else, and where are the rust spots in the sink? Are they around the drain or where porcelain has chipped?

I assume it's not a stainless steel sink, as those do not rust. Without that information, I can't tell you what to do about removing the rust.

Q. In the lower level of my house, there are three galvanized steel ducts bringing fresh air into the house. (One for the water heater room, one for the fireplace combustion box and one for the furnace cold air return.)

During cold weather, it was very cold working at my desk located immediately under these ducts. To keep them warmer, I placed fiberglass insulation along the rim joist and around the first few feet of each of the ducts. It no longer feels like cold air is pouring down as I work at the desk, but a condensation problem now occurs. Even though insulation completely surrounds the ducts, enough warm house air makes contact and cools with the condensation soaking the surrounding insulation. During extended cold periods, enough water will accumulate to drip out of the insulation. I'd like to fix this.

One thought is to use foam insulation purchased at a home improvement center. The other is some sort of form-fitting fiberglass insulation sleeve with a moisture barrier. There are some spots that are very close and/or limited enough to reach that the fiberglass would be very difficult to properly install. On the other hand, I wonder if at some later date, if I needed access to the ducts, the spray foam would be a serious problem. What are your thoughts?

A. The easiest solution is to install insulation specially made for air-conditioning ducts. It has a reinforced aluminum envelope, and compatible tape to tape the joints.

Q. Your common sense, practical advice and responses to homeowner queries have always been very useful and appreciated. My question is regarding replacement windows. We live in the western Pennsylvania area. Our Andersen double-hung, Thermopane windows have been in place for 33 years and seem to have held up very well until a couple of years ago. We now have several sashes that are pulling apart.

One unit has a significantly warped bottom sash and has separated at least one-half inch. These are white, vinyl-clad wood frames. The inside wood is stained to match our inside woodwork. Several of them have a deteriorating surface on the outside of the sash.

It is time to consider replacements. Therefore, I am interested in what would be a recommended brand and type of window. I do not want aluminum and I am not enamored of the vinyl frames. They seem "cheap" to me. I have seen vinyl-clad wood, which I assume is similar to our existing units. I have also noticed an interest in fiberglass. There are also some vinyl-clad frames in which the inner part is similar to wood particles. I am leery about that.

Our existing units have the "pop-in" style of mullion bars, which are a pain for window cleaning and expensive to replace. I like the idea of the mullion bars embedded between the glass. I also like the idea of the units that can be easily cleaned from inside the house, since we have a large two-story house. Low maintenance is also a consideration.

What are your thoughts and recommendations regarding these issues in selecting replacement windows? Which brands have a good balance of expense, window life and maintenance?

A. Look into Marvin Integrity windows. They have all the features you want and are very energy-efficient. We have them in our house and love them.

Integrity windows are either all-fiberglass or fiberglass outside and wood inside. You can have the grilles between the two glass panes, and the double-hung window sashes tilt in for easy cleaning.

Marvin also has a very good service policy. We called on them for adjustment to our sliding door screen several years after the door's installation, and they took care of it quickly and at no charge.

Q. I recently had my water heater replaced, and while the guys were here, they suggested a product called Aeroseal for my heating ducts. I have had my ducts cleaned a few times by my carpet cleaning company. These guys said that unless it is your specialty, they were not cleaned properly.

So my first question, is there really a huge difference between how ducts are cleaned from company to company? Secondly, have you heard of this Aeroseal product that is sprayed in the vents and supposedly seals any holes? What is your opinion of this, as in theory it makes sense for energy conservation, but I am leery of spraying a chemical into my ducts.

Thank you for your informational articles I read in the Herald, and for the information regarding this product!

A. Having heating and air-conditioning ducts cleaned every once in a while is a good idea. The frequency depends on where you live; if you live in an industrial or certain agricultural areas where dust and other pollutants are common, it may be advisable to have an annual cleaning.

But if you live in the country in a forested area or farmland with meadows grazed by cows and horses or regularly hayed, you may not need cleaning for several years, if at all. It also depends on your family lifestyle and housecleaning.

It is preferable to have the cleaning done by specialists, but if your carpet-cleaning firm is experienced in this and has the right equipment, you may be fine.

Aeroseal was developed by the Indoor Environment Program at Lawrence Berkeley National Laboratory, funded by the U.S. Environmental Protection Agency, the U.S. Department of Energy, the Electric Power Research Institute and the California Institute of Energy and Environment.

The data I reviewed sound interesting, but I have no personal experience with Aeroseal.

However, Aeroseal can only seal small leaks. If the ducts are accessible from the basement, the joints should be sealed with special tape. If they are in walls or floors and inaccessible, the advantage of sealing any small holes is that it makes the delivery of the conditioned air more efficient, especially for the more distant outlets.

Q. My question concerns our driveway, which was cemented in April 2013. We noticed this February that the cement is chipping and cracking. We contacted the company that did the work and they told us it was the sealer that was used and they could not do anything. They now called us back and said they had a few other people say the same thing happened to them. They are saying that it may have been the cement that was used or they put too much water in the cement when it was mixed. They told us they would get back to us; it has been about three weeks. I want to know if that is possible?

A. First, cement is one of the three components that make concrete; they are Portland cement, water and stone aggregate.

I don't think the sealer had anything to do with the chipping and cracking of your concrete driveway.

If by chipping you mean that the concrete surface is peeling off, known as scaling, it can be due to one of several causes: freezing and thawing of the surface; too early use of a steel trowel during the finishing stages of the concrete pour; over-finishing or finishing while there is still bleed water on the surface.

Cracking is usually due to a lack of control joints, but it can also be due to plastic shrinkage, freezing and thawing, settlement, etc.

Q. I have a large (42-foot by 24-foot) attached garage. All of the walls are insulated, but the ceiling is drywall only. I heat the space to 50 degrees during winter. This past winter, mold developed all over the ceiling in the space furthest from the heat source, where the cars are parked. I am removing the mold rather easily with Concrobium Mold Control, and repainting with Kilz Max primer/sealer/stain blocker. I noticed there was no mold growing on the rafter lines, only on the uninsulated drywall. Would insulation between the joists solve the problem? If so, how much insulation? Would you have any other suggestions? The attic space above the garage has eaves vents and roof vents. There is also a gable vent that I plan on sealing after I read one of your previous columns.

A. Your diagnosis sounds correct. The ceiling joists offer some insulation, enough for mold not to develop, but the drywall exposed to the cold air of the attic and to the moisture from the cars parked in that area allowed mold to grow.

Add insulation to the depth of the floor joists, and only seal the gable vent if you have a full-length ridge vent, which does not seem likely since you mention roof vents in the plural.

A cold attic over an area with temperature kept at 50 degrees Fahrenheit is not subjected to the same dynamics as one above a lived-in conditioned space.

• 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.

© 2014, United Feature Syndicate Inc.