Subzero temperatures can mean three-digit utility bills and a huge waste of energy if your home isn’t insulated properly. Adding insulation to your walls and attic isn’t hard and it can pay off immediately in huge energy and money savings. Here are some great tips that will show you fast and easy ways to insulate your home right.
By the DIY experts of The Family Handyman Magazine:February 2012
Here’s a faster, cleaner way to cut fiberglass insulation.
Use a hedge shears to slice through the insulation.
Unlike a utility knife, the shears won’t spread
loose tufts of insulation all over, and the best part is,
you stay itch free.
For easier cutting, temporarily flatten unruly fiberglass
insulation with a piece of scrap plywood.
Just cut a 1-1/2-in.-wide slot in the center of a 16 x
30-in. board, use the slot as a straightedge and
get a clean cut every time.
The key to a quality insulating job is tight-fitting batts
that completely fill the stud cavity with no voids or
gaps. Push batts all the way to the back of each stud space
and then pull out the front edges until they’re flush with
the face of the studs. You’ll need a utility knife with a good supply of
sharp blades, a tape measure and a straightedge, and a
3- or 4-in. putty knife for stuffing insulation around
doors and windows. Fiberglass can irritate your throat
and skin, so wear protective gear.
Split batts to fit around
electrical cables. Tear the batt in half, starting from the
bottom. Slide one half behind
the cable and lay the other half
over the top. If you have plumbing
pipes on an outside wall,
insulate behind them, but
leave the side facing the interior
uncovered to allow heat
from the house to keep the
Split and cut batts to fit
behind and around electrical
boxes. Slide half the batt behind
the box. Then trim the insulation
to fit snugly around the box.
Run your knife blade against
the outside of the box to
guide the cut. But don’t cut
too deep or you risk nicking
Cut batts to length by setting the top of the batt
into the space and cutting against the bottom plate
with a sharp utility knife. Leave an extra 1/2 in. of
length for a tighter fit. Unfaced batts are
easier to cut and install. In most climates,
you’ll have to staple 4-mil plastic sheeting
over the batts to form a vapor barrier. Check
with your local building inspector for the recommended
practice in your area.
Accurate cutting is essential
(actually, slightly oversized batts
are best). A batt cut too small
leaves gaps and one cut too large
bunches up and leaves voids.
There are two different methods.
For the “eyeball” method, leave
the batt folded in half and hold one
edge against the edge of the stud. Slice
down the length while holding the top of
the batt. Cut against the stud face.
If you’re having trouble getting an
accurate cut with the “eyeballing”
technique, press a straightedge
down on the batt at the desired width
and use it as a guide for the utility knife.
Add about 1/2 in. to the width to
ensure a tight fit. It’s better to
compress the batts a little than
to leave gaps. Don’t worry if the
batts bulge out a bit. The drywall
will compress them tightly.
The shim space around windows and doors is a
prime spot for air leakage. Stop these leaks by
reaching to the back of this space with the straw type
nozzle included with a can of expanding foam
insulation and applying a bead around the
perimeter. Let it cure at least an hour before stuffing
the remaining space with a thin strip of fiberglass.
The insulation should fit snugly, but don’t pack it.
Manufacturers now produce batts with higher fiberglass
densities, so you can buy 3-1/2-in.-thick batts with R-11,
R-13 or R-15 thermal resistance values. The higher the
number, the better the insulation. The high-density R-15
batts are best, but they cost more than twice as much as R-
11 batts. Balance the price with the insulation requirements of
your local building codes. In most cases, low- or medium-density
insulation is adequate.
Have the necessary tools for this DIY project lined up before you start—you’ll save time and frustration.
Avoid last-minute shopping trips by having all your materials ready ahead of time. Here's a list.
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