Use roller for interior paint jobs

Q. I want to give my house a complete interior painting, walls and ceilings. Is there a sprayer that a do-it-yourselfer can use indoors, or is a power roller the way to go?

A. So-called airless paint sprayers, which use an electric motor to propel the paint, are sometimes used for interior painting. Airless sprayers can be rented at many tool-rental agencies or can be bought at home centers (about $80 and up).

Another type of sprayer, called HVLP (high volume, low pressure) is also available; these are easier to control and have less overspray (stray paint) than airless sprayers.

However, the fact is that sprayers work best with thinned paints. Most latex wall paints and ceiling paints are relatively thick, to give good coverage and hiding power in a single coat, and they would need to be carefully thinned to work well in a sprayer.

Spraying also requires a great deal of masking, to prevent paint from getting where you don’t want it, and the inevitable cleaning of the equipment takes time.

Power rollers are somewhat more suited to indoor use, in my opinion, but also require careful cleaning if you take a long break or change paint colors or types. They can be rented or bought (about $100 and up for a good-quality machine).

Many painters, do-it-yourselfers and pros, prefer to use conventional unpowered paint rollers, adding an extension handle for ceilings and high wall areas.

These rollers give good control, and roller covers are cheap enough to be tossed in the trash when you are finished. They also allow you to use thick paints, like texture paints, if you want a special finish.

I have tried sprayers and gussied-up rollers, but always go back to an unpowered roller when I want to paint walls or ceilings.

Q. A neighbor told me I should have a chimney cap installed to keep squirrels out of my chimney. I don’t see any way that a squirrel could get into my house from the chimney, so do I really need a cap?

A. I have been an advocate of chimney caps ever since I found a dead squirrel at the bottom of my chimney.

I also had to open another chimney to free a trapped bird. So even if a squirrel can’t get into your house from the chimney, unpleasant things can happen.

Birds can also build nests in chimneys and create dangerous blockages. A chimney cap will also help keep rain out of the chimney and avert possible interior damage to the chimney or equipment connected to it.

Chimney caps aren’t expensive ($50 or so at home centers), though you might have to hire someone to install it.

Q. We had our family room expanded some years ago. Not long afterward, shadowy stains appeared on the exterior walls where drywall screws were inserted. I have primed and painted these stains three times, but they always show through. Can you help?

A. The stains are probably mold or rust. The stains resulted when moisture formed on the thinly covered screw heads because of excessive humidity in the room. Water vapor condensed on the cold screws and mold or rust formed.

If the stains had been treated soon after they formed, and before all that primer and paint was applied, you might have been able to remove them with a mild bleach solution or by scrubbing with a mild detergent.

You can try these treatments now, but it is unlikely you will be able to remove all the stains through the many coatings you have applied. I suggest trying a different stain killer, such as Zinsser’s B-I-N, which is pigmented shellac, and repainting just a small test area to see if the results are good.

Reducing the moisture in the room with a dehumidifier and better ventilation should also help.