Fall 2011
Ventilation and insulation inside of a home’s attic is important business. Period. The realization of proper attic ventilation is known, but misunderstandings of the inner-workings can allow improper ventilation to remain.
Entering the attic space is an ordeal in itself. It is a tiny, cramped, and dark space where bats, rats and booty traps (that’s what I said, booby traps) await unsuspecting homeowners. (Goonies movie reference) A fear exists that a person could be locked into the attic. Another fear is you could step on the wrong area and find yourself bouncing on the top bunk of a children’s bed where once entrapped, are forced to watch old family holiday videos in black and white. Have no fear, you simply wait for the family to return from Christmas shopping to open the hatch and release you. (National Lampoon’s Christmas Vacation, the second movie reference in this writing for those keeping track)
Attic ventilation can save money and improve energy savings when used properly. It may also decrease the likelihood that damage from improper ventilation may occur, not only to the home’s structure, but the health and safety of your family.
The first step to improving ventilation is striking a balance. Ventilation 101 states that when air or moisture comes in the attic, it must go out.
Picture courtesy of
cornerhardware.com
If no air is coming
in the attic from the soffit vents (the underside of a roof), the ventilation
system performs much like the “Tin Man” without oil: the system freezes up.
(The Wizard of Oz)
Literally, it does freeze in winter; think of a cave adorned with
thousand of beautiful ice crystals, except the cave is your attic and the ice
crystals are not supposed to be there. If you shoot an oil can at the ice, it will only make a mess.
Picture courtesy of
hailandwind.com
The moisture created
inside a home from aspiration (breathing), cooking, showering and whatever else
people do in the privacy of their own homes creates moisture that “escapes”
into your attic through the ceiling area in what professionals call
“conditioned air.” When I say “area” I mean any numbers of ways or
orifices that provide ready transport from your living space to your attic of
this “conditioned air.” They are too numerous to mention.
Here is an interesting quasi-fact for those wondering what kind of moisture is in an attic area. Several publications, private, governmental and some made-up, have estimates of up to six gallons of water a day that a family of four creates through these daily actions. S-I-X gallons. Go ahead family of four, fill up six milk jugs of water when you have a chance, then proceed to look up at the ceiling, now back at the water jugs, and back at the ceiling. Perplexed? The water in those jugs is going to be in your attic…everyday. If you do not have ventilation, where does that water go? Well, it soaks into your rafters, plywood, drywall and nestles itself into insulation voids, etc. Insulation and wet wood lose effectiveness and allow heat to escape through the attic, decreasing your energy efficiency.
Mold in the attic or homes have received quite a fair share of attention from many homeowners over the years. Mold needs three things in order to grow. It needs moisture, food and proper temperatures (32-120 degrees Fahrenheit). We already talked about where the moisture comes from. Now go ahead and add outside humidity to the six gallons, and we realize there is a lot of moisture in the attic space. What is “food?” Food for mold can be wood as it relates to an attic space. Wood could be the rafters, sheathing or even some types of insulation have paper products or paper backing of ceiling drywall. The third component mold needs to grow is of course the proper temperatures mentioned above.
Here is an interesting quasi-fact for those wondering what kind of moisture is in an attic area. Several publications, private, governmental and some made-up, have estimates of up to six gallons of water a day that a family of four creates through these daily actions. S-I-X gallons. Go ahead family of four, fill up six milk jugs of water when you have a chance, then proceed to look up at the ceiling, now back at the water jugs, and back at the ceiling. Perplexed? The water in those jugs is going to be in your attic…everyday. If you do not have ventilation, where does that water go? Well, it soaks into your rafters, plywood, drywall and nestles itself into insulation voids, etc. Insulation and wet wood lose effectiveness and allow heat to escape through the attic, decreasing your energy efficiency.
Mold in the attic or homes have received quite a fair share of attention from many homeowners over the years. Mold needs three things in order to grow. It needs moisture, food and proper temperatures (32-120 degrees Fahrenheit). We already talked about where the moisture comes from. Now go ahead and add outside humidity to the six gallons, and we realize there is a lot of moisture in the attic space. What is “food?” Food for mold can be wood as it relates to an attic space. Wood could be the rafters, sheathing or even some types of insulation have paper products or paper backing of ceiling drywall. The third component mold needs to grow is of course the proper temperatures mentioned above.
“Lucky for us we live
in a climate that can see subzero temperatures in winter, this will kill the
mold.” –Homeowner from Anytown, USA. This of course is untrue.
Mold is not killed in temperatures below 32 degree Fahrenheit, it merely
lays dormant until it can feast again.
A balanced air intake and exhaust is what gives attic ventilation the ability to turn the stale moist air in the attic into fresh air. If there is going to be an imbalance, it is better to err on the side of too much intake, the soffit vents. Moisture is not the only reason to move air out of the attic. Other pollutants including carbon monoxide, radon and mold can also be found in attics.
I only mention the winter and mold to show a side that is often misunderstood by homeowners. Heat buildup is not the only issue to solve in the attic. The winter air causes just as many problems.
Focusing on intake vents, those 8x16” metal screened openings you roll paint over every 10-15 years, are often underutilized or completely blocked off. They could be full of paint, bugs, dust or the most likely problem is insulation is blown over the top or insulation rolls shoved over them. Carter Exteriors, LLC is really good at painting also, and we do not paint over intake vents.
What could be the reason for intake vents to be covered by insulation? A couple of reasons are evident in a great contractor’s mind. The first being a push by the energy companies and the home energy audit boom. Let’s say your heating bill is a going up every year and you hear there is money to be “earned” on a tax credit to look into attic insulation. Sure enough you have an audit done and the energy auditors say there is not enough ventilation in the attic. I would say unless your home was built in the last three years, you do not have enough insulation; this is almost always the case. The suggested requirements for proper R-value has gone up considerably since the late 1970’s, and seems to get higher every year. Currently the Department of Energy recommends an attic R-value of R-49 to R-60 for zones five and six that we have in Iowa.
So as a result of this energy audit, reason number two comes to light. Either you go to the local home improvement store and purchase some bags or rolls of insulation and do it yourself, or you hire a contractor to come in and insulate the attic for you. This goes back to the start of this article. Working in an attic is a horrendous activity. Chances are once you are in the attic all you want is to get out as fast as possible. Working too quickly or with too little experience will lead to mistakes. One of those mistakes is going to be covering intakes up with insulation because, gosh darn it, this is hard work.
“Covering up a few of these won’t make much of a difference.” -Homeowner Anytown, USA. That is a big 0 for 2 Anytown, USA. Erring on the side of extra intakes makes all the difference as mentioned earlier. Why do all of our quotes come from Anytown, USA? Don’t we have anyone in Iowa we could quote? Moving on…
Mixing different types of roof ventilation is a common error. Ridge vent systems with box vents or adding a solar power vent, are sure ways to create ventilation problems if you do not already have them. Chances are there is not enough intake ventilation to warrant adding a secondary exhaust vent in the first place, even if it were the right thing to do, which it is not.
A balanced air intake and exhaust is what gives attic ventilation the ability to turn the stale moist air in the attic into fresh air. If there is going to be an imbalance, it is better to err on the side of too much intake, the soffit vents. Moisture is not the only reason to move air out of the attic. Other pollutants including carbon monoxide, radon and mold can also be found in attics.
I only mention the winter and mold to show a side that is often misunderstood by homeowners. Heat buildup is not the only issue to solve in the attic. The winter air causes just as many problems.
Focusing on intake vents, those 8x16” metal screened openings you roll paint over every 10-15 years, are often underutilized or completely blocked off. They could be full of paint, bugs, dust or the most likely problem is insulation is blown over the top or insulation rolls shoved over them. Carter Exteriors, LLC is really good at painting also, and we do not paint over intake vents.
What could be the reason for intake vents to be covered by insulation? A couple of reasons are evident in a great contractor’s mind. The first being a push by the energy companies and the home energy audit boom. Let’s say your heating bill is a going up every year and you hear there is money to be “earned” on a tax credit to look into attic insulation. Sure enough you have an audit done and the energy auditors say there is not enough ventilation in the attic. I would say unless your home was built in the last three years, you do not have enough insulation; this is almost always the case. The suggested requirements for proper R-value has gone up considerably since the late 1970’s, and seems to get higher every year. Currently the Department of Energy recommends an attic R-value of R-49 to R-60 for zones five and six that we have in Iowa.
So as a result of this energy audit, reason number two comes to light. Either you go to the local home improvement store and purchase some bags or rolls of insulation and do it yourself, or you hire a contractor to come in and insulate the attic for you. This goes back to the start of this article. Working in an attic is a horrendous activity. Chances are once you are in the attic all you want is to get out as fast as possible. Working too quickly or with too little experience will lead to mistakes. One of those mistakes is going to be covering intakes up with insulation because, gosh darn it, this is hard work.
“Covering up a few of these won’t make much of a difference.” -Homeowner Anytown, USA. That is a big 0 for 2 Anytown, USA. Erring on the side of extra intakes makes all the difference as mentioned earlier. Why do all of our quotes come from Anytown, USA? Don’t we have anyone in Iowa we could quote? Moving on…
Mixing different types of roof ventilation is a common error. Ridge vent systems with box vents or adding a solar power vent, are sure ways to create ventilation problems if you do not already have them. Chances are there is not enough intake ventilation to warrant adding a secondary exhaust vent in the first place, even if it were the right thing to do, which it is not.
I’ll take improper
roof exhaust venting for $500 Alex
Air will always
follow the path of least resistance. Of course air cannot be seen by the
human eye. Air is sneaky and passive-aggressive in nature, and overall
one must always remember, it cannot be trusted. Unlike air, the smoke
test never lies. Note: Please be advised; DO NOT start a fire next
to your home to create smoke. Smoke tests are not done by creating fires.
A smoke test will give a good picture of how the ventilation is working
in the attic, but should only be done by a trained professional using the
proper tools!
Ice Dams are caused by bad roof
ventilation and/or misplaced insulation. That is all for this subject.
It is that simple.
If installing soffit and roof ventilation
or insulation is such a terrible and horrible experience, why does CarterExteriors, LLC do it? Because we are tradesmen and it is what tradesmen
do, they get dirty and uncomfortable so you do not have to. It is what we
do and why we get paid. We do not end up getting that dirty because we
send the guy in the picture below up there to do the work. The problem is
his doesn’t come cheap.
Pink Panther
Registered trademark of Metro-Goldwyn-Mayer Studios & Owens Corning
FinanceFarmer
