Relining Chimney Flues
If you’ve been doing some research
about chimneys flue systems, or you’ve
had your chimney inspected by a
certified technician, there’s a good
chance that you’ve heard about flue
relining. What is flue relining? Well, the
best way to answer that question is a
quick lesson on chimney anatomy.
All chimneys have flues. The term
chimney refers to the entire brick or steel
structure, from top to bottom. But the
pipe that vents the products of
combustion from furnaces and fireplaces
is called the flue. And the innermost area
of that pipe is the flue liner. Flue liners
can be made from terracotta clay, poured
in places ceramic systems, or stainless
steel (Some natural gas burning units
can also be vented through aluminum
flue liners.) The primary purpose of the
flue liner is to ensure that all of the
products of combustion–soot, sparks,
heat–are safely vented from the fireplace
or furnace out of the top of the chimney,
with no chance of leaking anywhere else
before they are clear of the top of the
chimney structure. This way, there is no
chance of soot, sparks, or heat escaping
and causing a fire to the home. When
the flue vents gas appliances like
furnaces, boilers, and water heaters, the
flue liner ensures the containment and
proper ventilation of carbon monoxide,
an odorless, colorless gas that kills
hundreds of Americans in their homes
A proper inspection of your flue liners
using a camera scan system is one of
the most important parts of a chimney
inspection, and that’s why it is included
in every one of our inspections and
chimney cleanings. When flue liners are
damaged or have been installed
improperly, they must be repaired or
replaced to be up to proper safety
standards. Cracks or gaps in a fireplace
or wood-burning stove flue can greatly
increase the risk of chimney fires, and
increase their chances of their spreading
to the rest of the home.
Ensuring that a flue is properly sized for
a furnace or water heater is an essential
to making sure that harmful flue gasses
from furnaces and water heaters are
properly vented from the home.
Advances in energy efficiency have
created a perfect storm for improperly
venting gas furnaces and water
heaters–as homes become tighter and
tighter to air exchange to the outside in
order to keep the warm air in and the
cold air out (or vice versa in the summer
time), homes develop negative air
pressure relative to the outside.
This means that cold air from outside is
trying to force its way down your furnace
flue, which can push exhaust from the
furnace back into the house. Combine
this with increasingly efficient gas
heating units, which put out less total
exhaust (since they burn less fuel) at
lower temperatures (since more of the
heat from combustion goes into the
house), and you have a situation where
the furnace may vent poorly or not at all.
Poorly venting furnaces can result in a
buildup of carbon monoxide inside the
home that is deadly to humans and pets.
Often, when older homes have been
refitted with newer gas heating units, the
flues are vastly over sized for the units.
This can be fixed by relining with a
smaller size flue liner, ensuring the best
possible ventilation for your gas units.
When liners are damaged beyond repair,
they should be replaced with stainless
steel flexible liners. These liners are
extremely durable, and are in many ways
superior to original terracotta flue liners.
Their round shape gives them better
venting characteristics, and because
they can be installed in one or two
pieces for the length of the flue, there are
no joints that might deteriorate or
become disconnected. Their high quality
means they can take more heat that a
masonry flue liner – though the hottest
chimney fires can still damage them.
That’s why every stainless steel liner we
sell is manufactured right here in the
United States of America, and comes
with a manufactures fully transferable
forever warranty, which is good for the
life of the chimney.
We are fully licensed and insured for your
protection. We offer lifetime warranties on all
chimney caps and liners.
Contact Safe-T-Sweep Chimney Cleaners
today at 610-304-2400 for your free relining
estimate, or browse our website for more
information about us or testimonials.
We install stainless steel multiple
flue caps as well as single flue caps.
This is in West Chester, Pa.