Check your dryer vent
If cold air comes in through your dryer
vent, check outside where the vent goes
through the wall. The vent should have
a flap (or flaps) at the end to stop air
infiltration. Make sure there’s a flap
and that it’s not stuck open. If the
flap works well, check the caulking. If
it’s cracking and peeling away, it’s probably
allowing cold air to leak in. Cut
away the old caulking, make sure the
vent is flush against the siding, and
apply new latex caulk.
If the flap doesn’t close on its own,
try cleaning it and then spray silicone
on the pivot point. If the flap still won’t
close, replace it. A new vent costs about
$5 at home centers, and installing it will
only take about 15 minutes.
Start by cutting away the caulking
around the vent with a utility knife,
remove any screws and unclamp the
duct leading to the dryer. Slide the old
vent out of the wall, slip in the new one
and reattach it to the duct. Caulk around the vent flange.
Fill gaps around electrical boxes
The gaps around electrical boxes in exterior
walls and ceilings are breezeways for cold air. If
the gap between the electrical box and the drywall
is less than 1/4 in., fill it with latex caulk. If
the gap is bigger and lopsided, use foam sealant
that's formulated for use around doors and window
framing. The minimally expanding foam
won't drip down your walls.
Turn off the power to the electrical box and
use a noncontact voltage tester to ensure there’s
no power. Remove the cover plate. Spray the
foam around the box to seal it. After it dries, cut
away any protruding foam, add a foam gasket
(to reduce drafts through the box) and replace
the cover plate. Do the same around register
openings on the inside of exterior walls.
Seal leaky windows (Option 1)
Leaky windows are one of the biggest sources of energy
loss in a typical home. If you don’t want to cover your
entire window, a quick, low-cost solution is to seal
the gaps with removable caulk. A $4.50 tube seals five
3 x 5-ft. windows.
Apply the caulk over the cracks between the movable
parts of the window (sashes) and the stationary parts
(jamb) and between the two sashes. Keep the bead between
3/16 and 1/2 in. wide. Don’t run your finger over the bead after
caulking (the caulk will be harder to remove later). In the spring,
simply pull off the caulk. Clean off any residue with mineral spirits.
Seal leaky windows (Option 2)
If you don’t like the look of caulk on your windows all winter long,
cover them with plastic film instead. A $13 kit covers five 3 x 5-ft.
windows. The plastic also reduces window condensation and can
be used with curtains or blinds. The film is available for the
exterior and interior.
Apply double-sided tape (included) to the window casing. Cut
the film roughly to size with scissors, leaving a few extra inches on
each side. Starting at a top corner, apply the film firmly to the
tape around all four sides of the window. Use a hair dryer to
remove the wrinkles. When winter is over, take down the plastic
and pull the tape off the casing. The tape removes easily without
damaging the finish.
If you can feel the breeze and see daylight
under your entry door, it’s costing you big-time.
It also means you need to adjust
your door threshold or install a new door
sweep. Door sweeps start at $10. Usually,
the hardest part about replacing the
sweeps is taking off the door.
Start by adjusting the threshold.
Newer versions have screws that raise and
lower the threshold. Turn all of the screws
until the door opens and closes without
much drag and any draft is eliminated. If
that doesn’t work, or your threshold doesn’t
have adjustment screws, replace the
Close the door and pop out the hinge
pins with a pin punch to remove the door.
Set the door on a work surface and remove
the old door sweep. Caulk the ends of the
door, then install the replacement sweep.
Some sweeps are tapped into place and
stapled along the door bottom; others are
screwed to the side along the door bottom.
Caulk and cover room air conditioners
A room air conditioner keeps a section of the
house cool. The problem is, it’ll keep the room
cool all winter long if it isn’t covered properly. If
you have a window unit, the best solution is to
remove it so the cold air won’t flow through and
around it. If you decide to leave it in or you have
a permanently installed wall unit, grab some
removable caulk and a $4 window air conditioner
cover to keep out the cold.
Place the cover over the outside of the air
conditioner, fitting the sewn-in corner straps
over the bottom corners. Wrap the middle straps
under and up the sides of the unit, then hook
them over the top. Inside the house, apply
removable caulk around the air conditioner
where it meets the wall or window. If the air conditioner
is a built-in unit, permanently seal it
with latex caulk.
Fill gaps under sinks
Pull back the escutcheons on plumbing pipes where they enter
exterior walls and you'll probably see generous gaps around the
pipes. In cold weather, you might also feel the draft coming in. All
it takes is some $7-a-can expanding foam to seal those leaks.
Shake the can vigorously, then squirt the foam around the
pipes inside the wall. Don't completely fill the gap—the foam will
expand. If it expands too much and you can’t get the escutcheon
back on, wait for it to dry, then slice it flush with the wall with a
Find air leaks
Locating air leaks can be tricky. They're often so small as to be
hardly noticeable. To find them, follow a trail of smoke.
Close all the windows in the house, turn off all the fans and
exhaust fans, and shut off the furnace. Light some incense and
walk slowly around the outer walls of the house. Anywhere you
notice the smoke blowing away from something or being sucked
toward something, there's probably an air leak. Now that you've
found it, seal it!
Seal small attic holes with foam and caulk
Hot air rises, so leaks in the ceiling are even worse than leaks in
walls. And in many homes, this airflow through ceilings and into
the attic is the No. 1 source of heat loss. You can check for leaks
around ceiling light fixtures and the attic access door using an
incense stick. But the only way to detect other leaks is to crawl up
into the attic, pull back the insulation and look for them. Most
leaks occur where chimneys and electrical and plumbing lines
pass through the ceiling. Although the attic is a nasty place to
work, plugging these leaks is a simple project—mostly caulking
and foaming gaps.
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Stop a draft in 60 seconds
In exterior walls, electrical boxes
that hold switches or outlets can let
in a lot of cold air. Worse, they can
let warm, moist indoor air into walls,
causing problems like wood rot or
peeling exterior paint. One way to
stop the airflow is to seal the gaps
around them and the holes inside
them with caulk—messy and time-consuming.
But there's a much easier
way: With foam gaskets, all you
have to do is unscrew the cover
plate, stick the gasket in place and
put the plate back on. A pack of a
dozen gaskets costs about $3 at
home centers and hardware stores.