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SpaceNut

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Registered: 2004-07-22

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Introduction A improvement of Attic Insulating

Home improvements that cover understanding heat to cooling lose and costs to make a stable environment within the home.
Of course, that means insulating walls and ceilings to reduce those levels.

1. improving insulation can come in the form of blown in from holes placed in the outer wall. This added lose reducing can also come from inside the home as rooms are rehabbed as it ages. Ceiling means being careful while being in one's attic installing the fiber glass blankets to reduce energy use for cooling and heating during the seasons.

Improve Attic Ventilation: Introduction

Time:Multiple Days

Complexity:Beginner

Cost:Varies

A well-ventilated attic offers four benefits
It prevents mildew growth and rot on your roof's framing and sheathing by reducing moisture buildup.
It helps prevent ice dams in winter by keeping your roof colder.
It extends the life of your shingles by keeping the roof cooler in hot weather. (The manufacturer's shingle warranty usually requires ventilation.)
It reduces cooling costs in the warm season. The savings will be slight if you have a well-insulated attic space; greater if you have little insulation.
In this article, we'll tell you when you need additional ventilation, how to install several types of passive roof vents and soffit vent covers, and how to keep your ventilation system working. We won't cover fan-powered ventilation, since this type is usually not necessary.

As you will see, improving attic ventilation isn't expensive, time-consuming or difficult, even for the novice. Choose from one of these top attic fans to sort out your ventiliation needs. You only need basic hand and power tools. However, when you climb up on your roof, be sure to follow safety precautions. Before you buy one, get to know if attic fans are worth it.

CAUTION!
Asbestos has been found in some types of vermiculite insulation. Vermiculite, a lightweight material resembling gravel, was used as attic insulation in perhaps as many as a million homes. If you have vermiculite in your attic, don't disturb it unless you have a sample checked by an accredited laboratory. Disturbing it can release the asbestos fibers, which, once airborne, can enter your lungs and eventually cause lung disease. For a list of accredited testing labs, call your local department of public health. For more vermiculite details, go to the Environmental Protection Agency (EPA) (www.epa.gov) or call your regional EPA office.

Does your house need more vents?

Photo 1: Add air chutes
Install air chutes in each rafter space to keep the air path clear between the rafters and the roof sheathing. (Tip: Coat your arms, face and neck with talcum powder to reduce the itching from insulation.) Staple the chutes in place. Be sure to wear long sleeves, goggles and a dust mask. In some cases you may need to install a “wind wash barrier” of wood or plastic to close the gap between the top plate and the air chute, to prevent wind from blowing into the attic. Consult your local building inspector for more information.

Photo 2: Seal penetrations
Seal gaps around plumbing drain vent pipes, ductwork and electrical boxes with minimal-expanding foam or caulk. This helps keep warm, moist air out of the attic.

Photo 3: Clean soffit vents
Clear your soffit vents every few years with blasts of compressed air. Always do this to your soffit vents after you install air chutes because you'll probably knock insulation down into the soffit.

What a clogged soffit vent looks like close up
Soffit vent covers get clogged with dust and insulation. Here's how to clean dirty soffit vents.

Before you go out and start poking holes in your roof and soffits, check to see if you have the type of problem that attic ventilation can solve.

One common problem is caused by ice buildup along the edges of a roof. These ice dams form when warm attic air melts the snow on the roof and the water refreezes along the colder edge of the roof. The ice traps water behind it, allowing the water to seep back under the shingles and leak through the roof. Increased ventilation will make the entire roof cold and reduce or eliminate ice dams. Here's what you can do to prevent ice dams.

Another common problem is moisture buildup. After cold weather arrives, grab a flashlight and inspect your attic. Cover all your skin to protect it from the itchy insulation, and wear a dust mask. If your attic doesn't have a walkway, take two small (2 x 4 ft.) sheets of 1/2-in. plywood to move around on.

Here are the signs to look for:

Frost on the underside of the roof or rafters. Warm, moist air trapped in the attic condenses and freezes on the wood.
Water-stained or blackened wood. A sign of mildew or rot. You can also spot this in the summer.
Heavily rusted nails. A sign that condensation is forming on metal surfaces.
Matted-down insulation. A sign of roof leaks from ice damming or other causes.
If you have either ice dams or moisture buildup, improve your attic ventilation. Begin by making sure your existing system works (Photos 1 and 3), plugging major air leaks into the attic (Photo 2) and correcting any other of the common causes of poor attic venting. If those steps don't solve the problem, add more soffit vents, following the techniques we show in Photos 4 – 17. For help figuring how much venting you need, see “Minimum Venting Requirements,” below.

Even if you aren't having problems, bring your attic venting up to code when (1) you install new shingles and (2) you add attic insulation.

Five Common Causes of Poor Attic Venting
Problem 1: Insulation often clogs the space between the rafters, blocking air from traveling to and from the soffit area. Solution: Install air chutes or clear them if they're clogged (Photo 1).

Problem 2: Aluminum or vinyl soffits (eaves) installed over plywood soffits that don't have venting holes. Solution: Cut holes in plywood soffits as needed.

Problem 3: Gaps to the attic around plumbing pipes, ducting and electrical boxes. Many experts consider plugging these holes to be more important than ventilation. Solution: See Photo 2.

Problem 4: Rectangular roof vents installed on one side of the roof only. Rectangular roof vents work best when the wind blows over the top of them, rather than into them. Solution: Install rectangular roof vents on both sides of the roof.

Problem 5: Kitchen and bath fans vented into the attic. Solution: Vent these fans through the roof or soffit.

Add soffit venting first

Photo 4: Mark holes for soffit venting
Butt a cardboard template against the fascia and mark your soffit hole locations to begin soffit vent installation. Make the vent hole 1/2 in. smaller on each side than the vent you're installing. If you widen existing holes, widen them toward the fascia, but no closer than 3 in. from the fascia to avoid waves and ripples in the soffit plywood. Position the soffit venting holes between the rafters at equal intervals. You can find the rafters by locating the nailheads or using a stud finder. You can also try installing maintenance-free aluminum soffit vents, too.

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