Drafts Freeze
Pipes:
Frozen pipes are a bane to homeowners and a boon
to repair plumbers whenever bitter cold weather
cold weather with high winds occur.
With milder winter weather pipes in still air
rarely freeze while those in drafts are much
more vulnerable. Prevent drafts over your pipes
and you can breath easier during winter
weather.
Pipes freeze due to relatively large
"convective" or air current energy losses rather
than the relatively small "radiant" or energy
wave losses. Pipes located within Northern
exposure walls tend to be more vulnerable since
there is usually more wind.
A very practical do-it-yourself all-purpose
protective material for weatherizing piping is 3
1/2 inch foil-faced fiberglass blanket
insulation. Buy a roll of this for about $15 to
20 dollars along with some duct tape to protect
vulnerable pipes in your home. Here are some
particulars of the measures to take before
freezing weather strikes.
Make sure your outside water faucets are
drained. Turn the faucet on. If water flows, you
will have to go inside, locate the shutoff
valve, and close it. Go back outside and open
the faucet again. If the water between the
inside valve and the outside faucet does not run
out, you will have to go back inside and open
the little knurled knob on the inside valve
body, to release the vacuum. "Frost-free"
faucets do not require draining since their
valve stems extend straight back through the
wall and close off the water inside the house
where it won't freeze. Outside faucets fed
through garage spaces often have their shutoff
drain valves located in the garage. This often
leaves the supply portion of the pipe inside the
garage vulnerable. Have a shutoff drain valve
installed inside the heated portion of the
house.
Water meters located in shallow pits at curbside
often freeze because they are not below the
frost line which is approximately 30 inches in
Washington. If this happens, all the water to
the house will be cut off. Coordinate insulating
the meter pit with a reading of the meter by the
water company since they have a special wrench
to remove the cover. Wrap the meter and stuff
the pit with the 3 1/2 inch foil faced
fiberglass with the foil to the outside.
Inspect the supply pipes in crawl spaces and
basements, looking specifically for pipes
located where drafts can flow over them. Supply
pipes that run along the top of foundation walls
are likely to freeze due to drafts that seep
under the sill plate (the wood piece bolted to
the foundation and supporting the floor joists.)
To protect them, stuff fiberglass insulation
behind the pipes and between the sill plate and
foundation or tape over any gaps with duct tape.
Pipes passing close by poorly fitted basement
windows are equally vulnerable, so tape around
the window sash edges or staple plastic over the
frame.
Wrap vulnerable pipes with insulation. Cut the 3
1/2 inch thick rolls into four inch wide strips
and lay the strips along the pipes with the foil
to the outside. Fold the strips around the pipe,
overlap the edges, and tape securely with duct
tape. Studies show this method to be as
effective as any commercially available pipe
wrap and far cheaper and easier to use.
Next, check along the upper perimeter of the
foundation walls and look for pipes that run up
exterior walls; these tend to be drafty areas
and are particularly vulnerable if the wall is
uninsulated or faces North. Shove insulation
behind these pipes if you can. Double check
additions which have plumbing pipes run under
them and carefully look for piping in the
vicinity of any new vents added to dry out a
damp crawl space.
Recently insulated crawl space flooring can
allow pipes to freeze by cutting off heat from
the living space above that previously protected
them. Play safe by insulating all crawl space
supply pipes. For extra measure, wrap up drain
line traps as well. Slow draining fixtures
should have their drain lines wrapped since they
are much more vulnerable to freezeups in the
winter.
Open the cabinet doors beneath the kitchen sink
and see if the hot and cold supply pipes come
through the wall or floor. Pipes coming through
outside walls are more vulnerable and should be
considered for added protection. You can provide
a small measure of protection by allowing the
taps to drip overnight and by leaving the
cabinet doors open so the kitchen heat can reach
the wall. A thorough job will require breaking
into the wall and wrapping the pipes. Check
laundry tubs and washing machines located on
exterior walls to be sure there is some heat
available.
Baths above unheated garages tend to be more
vulnerable particularly if they are located
close above drafty doors garage doors.
Weatherstrip the garage door and have a
contractor blow in insulation into the floor
cavity. Baths built within projections that
extend beyond the foundation or lower wall, such
as in a bay or dormer, often have vulnerable
pipes in the floor. Open the floor, wrap the
pipes individually, and insulate the flooring
with six inch foil faced blanket insulation.
Baths that back up to each other beneath attics
often have a wide cavity wall, called a chase,
between them which houses the servicing pipes.
It is common for insulation above this to have
fallen into the cavity, leaving the pipes
vulnerable to a freeze from cold drafts falling
down from above. Seal off the top of the chase
with air barrier material and cover with
blankets of fiberglass insulation or with
regular attic insulation.
Cape Cod houses with an added second floor bath
often have supply pipes left unprotected in the
sidewalls behind the short wall that joins the
floor to the sloping ceiling. Get behind these
"knee" walls and wrap the pipes.
This is relatively simple preventive work and is
wisely done in preparation for cold and windy
weather.