Continuing debate: cellulose, fiberglass?
Q. My house needs help. It was built in the '60s, so what kind of insulation should I use in the walls? Cellulose or fiberglass? I have to replace my single-glazed steel casement windows. Should I replace with sliding windows or new casements?
S. SUSSMAN, Lexington
A. Cellulose vs. fiberglass. It has been a long argument. Cellulose is the insulation of choice. It is inexpensive, made from recycled materials, is fire resistant thanks to its treatment with chemicals, is easily blown in, and will not settle. Fiberglass is good, too, but it has a lower insulative value.
As for windows, you need double-glazing (two layers of glass), and casement windows are the way to go. Horizontal sliders are a different style, are awkward to open and close, and more difficult to weatherstrip. They also ventilate only half the opening (like double hungs), while casements allow venting the full opening. Another advantage to casements is when they are open, they act as a baffle to direct cross-winds into the house for better cooling. One disadvantage: If you leave them open in a rainstorm, the whole window will get soaked.
Q. I have two fireplaces in my 1960s house, one above the other on the first floor and in the basement. When I burn a fire in the first-floor fireplace, smoke comes out of the fireplace in the basement. Why is this happening and what can be done about it?
EATING SMOKE
A. Chances are that the first-floor fireplace is pulling air out of the room and out of the basement and into the fire for combustion purposes, creating a downdraft in the basement fireplace. Then when smoke rises to the top of the chimney, the downdraft in the other chimney brings some of that smoke down the other flue in the chimney, shooting smoke into the basement.
A possible cure is to open a window in the first-floor room, which will give the fireplace its own air and stop the downdraft. To prevent cooling of that room, install a duct from the outdoors to the front of the fireplace. Putting chimney caps on each chimney also will help. Or, extend the flue liner in the first-floor fireplace chimney, which will discourage transfer of smoke from one to the other.
A final trick: Put a top damper on the flue of the basement fireplace.
The beautiful weather seems to preclude a fireplace problem, but at least you will have several months of nice weather to make all those corrections before you have to burn a fire in one of those fireplaces.
Globe Handyman on Call also appears in the Sunday Homes section. He's available 1-6 p.m. Tuesdays to answer questions about house repair. Call 617-929-2930. Hotton (photton@globe.com) also chats online about house matters 2-3 p.m. Thursdays. Go to www.boston.com. 
