Dear Gene: We live in a two-level house with most of
the living space on the upper floor. The air-conditioner thermostat is on
the upper floor, which gets very warm in hot weather. We are thinking of
having a couple of electrically powered attic fans installed to help cool
the upper floor. What is your opinion? Will we save energy? — S.F.
The belief that attic fans will help cool living space
by pumping hot air out of an attic is widespread, but I am not one of the
believers. I think your most important bulwark against heat infiltration
from the attic — and against loss of cooled or heated air from the
living space — is insulation on the attic floor. In warm Southern
climates, a radiant barrier (a reflective surface) under the roof sheathing
can also be effective in reducing attic heat. For more information on
radiant barriers, check the Web site of the Florida Solar Energy Center
(www.fsec.ucf.edu); type “radiant barriers” in the search space
at the top of the home page. Independent studies have shown that electrically
powered attic fans can actually increase energy costs in air-conditioned
homes by using electricity and by pulling expensively cooled air into the
attic and expelling it to the outside. And if the attic floor is well
insulated, attic fans will have little or no effect on the temperature
below the insulation. Another claim is that fans create a dangerous
“backdraft” in the attic that can pull hazardous combustion
products such as carbon monoxide into the living space from water heaters
and other combustion-type appliances. My advice is to increase your attic-floor insulation
to at least R-30 (about 10 inches of fiberglass or cellulose) and forget
about the fans. You should, however, have a good natural ventilation system
in the attic, usually consisting of vents in the soffits (under the eaves),
on the ridge of the roof, and in the gable ends.
Dear Gene: I have a concrete driveway. Can I seal it
myself, or is this a job for a contractor? Where do I get the sealer?
— D.M.
Sealing a concrete driveway is not difficult, and many
homeowners do it themselves. Concrete sealers are available at most home
centers and building-supply outlets. A widely sold one is UGL’s
Drylok Masonry Treatment (www.ugl.com). A long-handled roller is a good
application tool. Clean the driveway first by blowing or sweeping off
dirt and debris, and remove any stains with a concrete cleaner or
degreaser, also sold at most home centers. Sealing the driveway will help prevent dusting and
chipping of the concrete and provide some resistance to stains.
Dear Gene: I have a walkway made of flagstones set in
concrete. Several of the flagstones have come loose, and the mortar around
them is cracked and loose. How can I reattach the loose stones, and what do
I use to fill between them? — P.Z.
Buy a bag of dry mortar mix and a small trowel at a
home center. You will just need to add water to the mix and follow
directions on the bag to prepare the mortar for use. Lift out the loose
stones, clean out the area underneath, and spread a layer of mortar about a
half-inch thick. Set the stones into the mortar and wiggle them until they
are firm and level with the surrounding stones. Fill in around the stones
with more mortar mix and smooth it with the trowel.
TOOL TEST: Homeowners
looking for an inexpensive compact air compressor to inflate tires, toys,
and the like, and possibly perform other tasks such as powering air tools,
will find several good candidates at home centers. One is Husky’s new
model FP2070 (about $100 at Home Depot), which I recently tested. The Husky
is cordless — it operates on rechargeable batteries that make it
easily portable — and has several other bells and whistles that set
it apart, along with surprisingly powerful performance. This compressor is about the size of a five-gallon
bucket but generates as much as 135 psi (pounds per square inch), enough to
operate some air tools such as staplers and brad nailers. The compressor
has a comfortable bucket-type carrying handle, and the accessories include
a tire chuck and several other inflating tools. In addition, there is an
AM-FM radio and a 12-volt power outlet for running direct-current tools and
recharging cell phones. I would appreciate a more comprehensive
owner’s manual with larger type and better illustrations, but on the
whole this is a potent and versatile package for the money.
This article appears in Jun 29 – Jul 5, 2006.
