HEATING AND COOLING YOUR LOG HOME
Needless to say, our forefathers didn't worry too much about
heating their log cabins. Big fireplaces had no problem warming
up the one or two rooms they lived in. Of course now that log
homes are family-sized, people often have the impression that
there is something different about how they are heated, and the
good news is that a standard system will work as well in a log
home as a traditional structure.
Almost all log homes are built with at least one fireplace.
Initially, we thought that our beautiful soapstone woodstove
would heat the whole house, and we would use our forced-air
propane heat as a backup. Alas, we were all wrong. Because we
have a cathedral ceiling with a big loft, the heat from the
stove goes directly upstairs, requiring two ceiling fans to
recirculate the warm air. We expected this, but we also thought
the heat would expand sideways into the rest of the open floor
space (dining room and kitchen). Not on your life! Even sitting
on the couch about 15 feet from the stove, I need a coverlet.
I'm uncomfortably chilly in the kitchen. I think that if we had
a regular ceiling, the heat might have gone where we expected
it, but the volume of the cathedral ceiling threw off our
calculations. Also, the soapstone stove is designed to be run
24/7, and because we both work for a living, the stove doesn't
get fired up until the evening. This woodstove needs to be
heated up slowly at the risk of cracking the stone, so by the
time it's really cooking we're ready for bed.
Old-fashioned fireplaces traditionally sucked all the warm air
out of the room, but modern designs are more efficient at
recirculating the heat. The most energy-efficient fireplace is
built in the center of the house, so the stack heat is not lost
to the outside. Outside stacks can create back drafts if the
fire is extinguished, making a new fire more difficult to light.
If you are planning multiple fireplaces, putting two of them
back-to-back (facing adjoining rooms) will give you the
opportunity to build one chimney with two flues. Or you could
put a fireplace above your furnace, again allowing two flues in
the same chimney. A direct-vent fireplace will eliminate the
chimney, but you'll have to figure out how to hide the vent on
the outside wall. Or, if you use a wood-stove, you could run the
pipe through the wall and straight up the outside, building a
box around the pipe to simulate a chimney. Depending on the look
you want, you may want to leave the pipe inside the room and
send it through the roof. This will give more heat.
It's a good idea to consider your heating and air-conditioning
needs early in the design phase. Although log homes are
naturally energy-efficient, it's not wise to skimp on your
system. You may be able to heat your whole house with a huge
fireplace or wood stove, but the township will probably have
minimum standards to meet before they issue a building permit.
Also, you need to consider resale value. I know of one person
who tried to sell a million-dollar handcrafted log home without
a furnace, and as you might suspect, the buyer never came along.
The house was listed as unfinished, and installing the heating
system after the fact was too daunting a task. A similar problem
exists if you try to get away without central air conditioning.
Yes, log homes do stay cooler in the summer, but those "dog
days" of August can give you a perfectly miserable night's
sleep, and a potential buyer will probably not be as tolerant as
the original owner. Indeed, our mortgage company would not
consider granting a construction loan if we didn't include
central air conditioning.
If you want to preserve ductwork space, you can use forced air
heat, with the same ductwork serving the air conditioner.
Propane or oil are usually the fuels of choice in rural areas.
If your interior wall space is limited, there are companies that
specialize in very small, high-pressure duct systems that fit
into tight angles; these systems usually require a much higher
initial installation cost. When using traditional ductwork, you
want to keep the angles at a minimum, so it helps to design
first floor walls that will conveniently carry the air straight
up to the second floor. An open floor plan offers a challenge,
because you must bear in mind that the upstairs rooms need to be
heated somehow, and you will need both supply and return vents
to create an efficient air flow. If you want to use full log
interior walls, you'll have to find another way to run the
ductwork, electric, and plumbing. We made that mistake, and
there are not enough return vents in our bedroom. The air is
stuffy in the summer time, even with the windows open.
Where do the vents go? Since all our exterior walls are full
log, many of our vents were placed in the floor. If your
interior walls are sheetrock or tongue-and-groove, you can put
the vents where they normally go. One thing I wish we had done
was go over the plan with the HVAC contractor, because he put
the vents in places I found most inconvenient. Some times it can
be helped, and some times it can't.
If you are energy-minded and prefer to leave your thermostat at
a minimum, you will find that the southern-facing side of the
log home tends to be warmer than the northern exposure. Because
the sun tends to sink closer to the horizon on a winter
afternoon, it's advantageous to arrange your large windows
facing south; during the summer, the sun will cross over the
roof, so it won't overheat your house. However, you may find
that the northern side of your house - which won't get direct
sun at all - could be noticeably cooler. The best solution is to
install radiant-floor heating (if you can afford it). Although
this system requires a boiler instead of a furnace, the in-floor
heating spreads the warmth evenly throughout your home,
eliminating the northern-facing blues. With radiant-floor
heating, you need to keep the thermostat steady all the time;
the system is not designed to be turned down when you go to
work. Additionally, you can use the boiler to heat your hot
water as well, eliminating the need for a hot-water heater. On
the other hand, you will still need to install ductwork for the
air conditioning.
Overall, the same considerations apply as in regular
construction. We thought we could get by with only one zone of
heating and cooling, but in retrospect, two zones would have
solved a lot of problems. In the long run, it's cheaper to do it
correctly in the first place. Retrofitting a log home is not
going to be a breeze!