Q. I have a 10-foot-by-12-foot tool shed in a shady area with a roof covered with unsightly lichen. Can you suggest any relatively simple way to remove it before I paint the shed?
A. Ah, yes, lichen raises its ugly head once again. It is hard to remove sometimes, but try this: Wet it heavily and try scraping it with a flat, wood spatula. If you start gouging the asphalt, stop and live with it.
Q. I would like your opinion re: replacing a boiler in a forced hot water system with a high efficiency gas boiler versus a standard boiler. My local plumber says I would be better off with a standard boiler in a forced hot water system.
A. I’d go along with your plumber. If your system is gas fired, nothing else is needed. If you are converting to gas, then you will probably need to put in a stainless steel flue liner, but it’s worth the savings in the cost of fuel.
Q. I would like to reconfigure a small half bath. The toilet is next to an outside wall. I want to install an elevated toilet but it would jut out too far forward. The opposite end has a linen closet that I could eliminate. I wonder if the toilet could be placed there facing sideways instead of forward. Between the toilet and the closet is a sink vanity that could be replaced with a pedestal, giving additional room. Can it be done without prohibitive plumbing costs?
A. If the sideways toilet will have enough leg and knee room, I see nothing wrong with it, if the toilet hole is not moved. Again, if you have a long-standing plumber, rely on his expertise.
Q. Periodically over the years, our unfinished basement took in water during heavy rains. The concrete slab has taken a beating; there is effacement in several places on one side of the basement and efflorescence in other areas where the concrete has not chipped or flaked away. Many years ago, a previous owner painted the slab and cinder block walls gray and from eye level, the floor now looks like the surface of the moon and trace amounts of concrete dust still come up. Since we installed a sump pump and new gutters after Hurricane Irene, we haven’t had a water problem; the Lolly columns look fine and there are no major cracks or gouges in the slab. (We’d really rather not replace the concrete.) Is there a tintable product you would recommend that would provide some cosmetic improvement and prevent more concrete dust from coming up?
A. If you don’t plan to use the basement as good living space, I don’t see why you should spend good money toward improvements, which will be pricey. But the floor can use some help, and I suggest you apply large ceramic tiles to the floor with thin-set mortar. The mortar will help level out defects or gouges, vagaries, and the big good-looking tiles may encourage you to consider the basement for living space.
1-6 p.m. Tuesdays to answer questions on house repair. Call 617-929-2930. Hotton (email@example.com) also chats online about house matters 2-3 p.m. Thursdays. Go to www.bostonglobe.com.