Typical Issues And Errors During Roof Ventilation

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Typical issues errors during Roof Ventilation
Alright so as the title suggests, this article is
all about roof ventilation. We receive a ton of
requests where clients ask our expert opinion on
what are the most common issues and errors with
roof ventilation, therefore as a leading
contractor for Roofing Charlotte NC it is our
prime responsibility to spread awareness on the
matter. Asphalt shingle manufacturers require
roof ventilation to help preserve the life of
the shingles, despite the fact that the colour of
shingles will have a greater effect on their
life expectancy than roof ventilation will. An
attic with insufficient ventilation will get
warmer than a well ventilated attic, which may
increase the temperature of the shingles, which
may decrease the life of the shingles just a
little. Proper ventilation will also help to
keep the attic space cooler during the winter,
which may help to prevent ice dams. Let me say
that again proper ventilation may help prevent
ice dams. Im not saying it will, but it might.
The same thing goes for frost in the attic
proper ventilation may reduce frost accumulation
in attics, but it wont prevent it.
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In other words, roof ventilation certainly isnt
a cure for any condition, but its still
required. Roof vent manufacturers publish
installation instructions that are easy to read
and should be easy to follow, and roof
ventilation is required in section R806 of the
building code, but a lot of folks either dont
read the instructions or they dont care. Today
Im going to go over a few of the most common
roof vent installation issues. Weather in
Charlotte NC can be surprising therefore you want
to ensure ventilation system on your roof is
intact. To avoid potential damage to your home
and finances, its important for you to know the
basics of roofing ventilation, and choose an
installation expert for roofing in Charlotte NC
that knows how to properly ventilate your homes
attic or rafter system. Condensation
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• Condensation when water vapour cools and
  becomes a liquid can occur inside homes and
  buildings, and often leads to damage and
  deterioration. Condensation can occur when there
  is high interior humidity and the temperature of
  interior building components is at or below the
  dew point temperature.
• Condensation that forms inside home attics and
  buildings can be caused by the use of washing
  machines, dish washers, bathtubs, showers,
  tumble dryers, humidifiers, hot tubs, and
  swimming pools unless these items are properly
  ventilated. In many instances the condensation
  is bad enough to be mistaken for a roof leak.
• Condensation can be eliminated by one, or a
  combination, of the following
• Reducing or eliminating the source of moisture.
• Raise the temperature of interior surfaces above
  the dew point temperature (this temperature will
  vary, depending on the relative humidity).
• Install proper ventilation.
• Mixed Exhaust Vents
• For proper ventilation, both high and low vents
  should be installed, most contractors for
  roofing in Charlotte NC seem to overlook the
  importance of mixed exhaust vents. On paper, the
  high vents are supposed to act like exhaust
  vents while the low vents should act like intake
  vents. Convection is supposed to help make this
  happen. In reality, it all depends on how the
  wind blows, convection has little to no effect,
  and its never perfect. The intake vents will
  typically be soffit vents, while the exhaust
  vents may consist of ridge vents, turbine vents,
  box vents, or powered vents but only one of
  those.
• The photo below shows an example of these
  different types of vents, all installed on the
  same roof, which is a no-no.

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When different types of roof vents are installed,
there is an increased potential for air in the
attic to basically short-circuit. In the photo
above, the power vent would probably end up
sucking in air from all of the other high vents
in the photo, while pulling in just a small
amount of air from the lower soffit vents. The
solution here is to install only one type of
exhaust vent. Crooked Turbine Vents Ive never
been a huge fan of turbine vents because I have
it in my head that they may end up causing some
of the same problems that powered roof vents do.
The one thing Ill mention is that turbine vents
need to be installed perfectly level when
theyre not installed level, they dont turn. In
the photo below, the vent on the left wasnt
level. Do you see anything else thats wrong in
the photo?
The other thing about turbine vents is that they
really do pull air out of the attic if air
sealing hasnt been performed in the attic,
theyll pull air into the attic from inside the
house, and shouldnt be used. That bears
repeating do not install turbine vents if the
attic has not been professionally air-sealed.
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Insufficient intake vents Current standards
specify a 50/50 split between high vents and low
vents, but how are low vents supposed to be
installed in a house with no soffits?
You can ask a lot of companies for roofing in
Charlotte NC and yet the answers may not satisfy
you. We got you covered here, you see, without
any low vents, the high vents will tend to pull
conditioned house air into the attic through
attic air leaks. One solution would be to
install fascia vents, and another less desirable
option would be to install a bunch of box vents
low down on the roof. Whats the Best Type of
Ventilation? Attic ventilation is an important
part of roofing. Proper attic ventilation
extends the life of a roof and reduces problems
because it minimizes the temperature
differential between the attic and the air
outside. Proper ventilation will remove moisture
and heat from the attic. Trapped heat and
moisture can raise energy costs, cause ice
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dams, and damage roof system components as well
as structural and personal items located inside
the attic where temperatures can easily reach
150 F (65 C). The best type of roof
ventilation for most homes occurs when cooler
air can enter the attic through soffit or fascia
intake vents. These vents can be seen from the
ground and are located behind the gutters. As the
cooler air warms and rises, the warm air is
vented out through exhaust vents mounted on or
near the top of the roof. Both intake ventilation
and exhaust ventilation installed at an
approximate one to one (11) ratio are required
for maximum air circulation. One square foot of
ventilation per 300 square feet of attic floor
space is a general guideline and is a code
requirement in some areas.
Free Roof Inspection If you have more questions
on ventilation errors or other issues related to
roofing in Charlotte NC get to https//www.alpha-
omegainc.com/ you can also schedule a free, no
obligation inspection, consultation and estimate.