Can Insulation Be Packed Too Tightly Above A Cold Air Register?

By Joseph Truini

At that place's no doubtfulness that a well-insulated dwelling house stays warmer in winter, libation in summer, and saves you money all year round through lower free energy bills. And reducing free energy consumption is particularly important nowadays every bit the toll of natural gas, propane and dwelling house-heating oil continues to rise.

Everyone knows that it's crucial to insulate the exterior envelope of the home, especially the exterior walls and floors above crawlspaces and basements. But few homeowners realize that the very most important identify to insulate is the attic floor. And that'due south an outcome because cranium floors are often woefully lacking in insulation.

A poorly insulated attic floor will allow heated air from below to migrate up into the cranium, creating dank rooms and costing you money. And in extreme cases, the heat leaking into the cranium tin can warm the underside of the roof, which melts snowfall that can lead to damaging ice dams. And in summer, inadequate attic insulation can make the rooms below stifling hot, which puts undue stress on your air conditioning system and uses more electricity.

So, how do you know if your attic is properly insulated?

Hither'south one simple way: Take a peek up into the cranium. If you tin see the tops of the ceiling joists, then you don't have plenty insulation. More often than not speaking, regardless of where you live in the country, you lot should have about fourteen to 16 inches of insulation on the floor of your cranium. That'due south equivalent to approximately R-sixty; for comparison, R-30 insulation is most 9 inches thick.

(The R-value measures the effectiveness of insulation to resist to the passage of estrus through walls and ceilings. The college the R-value, the greater the energy efficiency of the insulation.)

The good news is that adding insulation to an attic is very DIY-friendly and you tin can use virtually whatsoever type of insulation, though the most popular and affordable past far are fiberglass batts or rolls, mineral wool batts, and loose-fill fiberglass or cellulose. When calculation fiberglass to an cranium that already has some existing insulation, information technology'due south important to utilise un-faced insulation, which does not take kraft newspaper or foil wet barrier practical to one side.

In the unlikelihood that your attic has no insulation, then starting time install faced insulation, making sure the facing—paper or foil—is placed downwardly against the behind of the drywall ceiling. (Insulation facing should e'er face toward the conditioned space, meaning the expanse that's heated and/or air-conditioned.) Then you can enhance the energy efficiency of the attic by laying un-faced insulation on top of the existing insulation.

It'southward hard to give verbal costs for insulation since prices vary widely from region to region, only here are some ballpark estimates for un-faced R-19 insulation, which is about 6 inches thick: fiberglass batts or rolls, 75 to 90 cents per square pes; mineral wool batts, $1.70 to $1.ninety per square foot; loose-fill up fiberglass, 40 to lx cents per foursquare foot; loose-fill cellulose, 30 to 50 cents per foursquare human foot.

Loose-fill up insulation is also known as diddled-in insulation. It's typically installed using an electric blower and long hose, but you can likewise simply spread the loose bits of insulation across the attic flooring by hand or with a leafage rake. Caution: When installing any type of insulation, it'due south important to habiliment long sleeves, pants (not shorts), snug-fitting eye goggles, and dust mask. I'd also advise wearing a difficult lid or some kind sports helmet to protect your noggin from inevitable run-ins with the roof rafters.

Okay, so we know that a properly insulated attic volition reduce energy consumption, lower utility bills, and make your home experience cozier throughout the year. Nevertheless, to fully realize these savings and benefits, information technology's imperative that the insulation is installed correctly. Hither are six pro tips for properly insulating attics:

1. Seal All Ceiling Penetrations

Before you start adding new insulation, take a close look at the attic floor and you'll likely meet many holes where wires, pipes, hoses, vents and other mechanical components poke upward into the cranium. The small gaps around these penetrations allow warm air to seep into the attic. Prevent this by sealing all gaps with fireproof caulk, which is often labeled as burn stop or burn barrier. Do not use regular caulk to seal these penetrations, information technology's not burn-code compliant.

2. Make full All Voids

The number 1 attic-insulation error is leaving gaps and spaces between and around the insulation. Insulation can't do its job if it's non completely filling all voids between the joists. Even the smallest, seemingly insignificant gap allows warm air from the business firm to leak into the cranium. That not but wastes energy, but besides makes your furnace work harder, which can eventually shorten its life.

And so, be certain to cut and fit the insulation to fill each and every gap, but don't force information technology down into spaces. Compressing insulation reduces its effectiveness (see tip No. 5). And when installing batts or rolls of insulation, lay them perpendicular to the ceiling joists, butting them tightly together. Laying the insulation beyond the joists will ensure total, gap-gratis coverage.

iii. Beware of Vents

Nearly homes take vents that allow fresh air to enter and go out the attic. The abiding airflow helps exhaust moisture and condensation and prevents the growth of mold and mildew. Attic vents are typically installed in the soffit, forth the underside of the eave, along the ridge at the peak of the roof, or on the gable ends of the firm.

When insulating an attic, exist careful not to put whatever insulation over the vents, which will block airflow and cause a myriad of troubles. Be especially careful when using loose-fill insulation, which can easily be accidentally pushed or blown over vents.

iv. Expect for Recessed Lights

If there are standard recessed lite fixtures in the ceiling below the cranium, be conscientious non to lay insulation on tiptop of the fixtures. These lights create a tremendous amount of oestrus, which could ignite the insulation and cause a house fire. Continue all insulation at least three inches away from recessed lite fixtures. Note that this warning relates simply to standard Non-IC recessed fixtures.

If the recessed fixtures are IC-rated—which stands for Insulation Contact—then you can safely lay insulation right on top of the lights. If you're not sure which blazon of recessed fixtures are installed in your home, call in a abode inspector or licensed electrician. And continue the insulation well away from the fixtures until a determination has been made.

5. Compressing the Insulation

Another mutual mistake that DIYers make is tightly stuffing insulation into place, which seems to makes sense since you're trying to block out cold air. Still, the exact reverse it true and here's why: Insulation is typically rather soft and fluffy because information technology's filled with air, and that trapped air helps insulate. If insulation is compressed besides tightly, the air is forced out and the insulation loses much of its insulating value. And then, when installing insulation to your attic, avert stuffing it too firmly into place.

6. Don't Forget the Attic Entry

Nigh attics have an access panel, hatch, fold-back door or pull-downwards staircase. It's of import to insulate these admission openings to block the flow of warm air into the attic. And some of these openings can be pretty big—8 to 10 sq. ft.—which would result in some serious oestrus loss.

You could simply lay insulation on top of the access opening, only then you'd have to button it out of the way and reposition it again each fourth dimension you go into the attic. A better solution is to buy a ready-to-install insulated cranium door or attic stair cover. These products provide an easy way to create an airtight seal over the attic admission and they're quick to install and relatively affordable starting at about $lx.

[Sidebar]

Recommended R-Values for Cranium Insulation

The map below shows recommended R-values for attic insulation in viii dissimilar regions—or zones—in the U.S. Note that there are R-values for attics with no insulation, and also for attics that accept currently 3 to iv in. of existing insulation.

Climate Zone No Existing Insulation 3 to four Inches of Insulation

Zone 1 R30 to R49 R25 to R30

Zone 2 R30 to R60 R25 to R38

Zone 3 R30 to R60 R25 to R38

Zone iv R38 to R60 R38

Zones 5 – 8 R49 to R60 R38 to R49

Source: U.S. EPA and EnergyStar.gov