Should Attic Insulation Touch The Roof?


Cold weather is no joke! Especially with increasingly colder temperatures, you will need as much insulation as you can get. However, you may be wondering, can insulation touch the roof?

Your attic insulation should not touch the roof. You will need to place plastic or foam baffles in between the attic insulation and the roof to allow airflow and decrease the possibility of mold in your home.

We will talk more in-depth about why you shouldn’t have insulation on your roof, the advantages of insulation in your attic, what materials you should use, and the step-by-step typical process on how to insulate your attic.

Why No Insulation?

  • Too much insulation can increase your energy cost
  • Insulation on your roof can reduce the amount of airflow in your home.
  • Anything that seeps into the roof can get onto the insulation. Mold will grow on the insulation, and the air coming from the vents will make you breathe in toxic air, which has countless side effects. Source

Advantages Of Insulation In Your Attic

  • Using foam insulation helps keep your electricity bill low when used effectively!
  • Insulation makes your home a lot more cost-effective (less mold, less air conditioning, etc.)
  • Attic Insulation is very environmentally friendly
  • You can avoid damage to your home through moisture when you put in your insulation well.
  • Attic insulation will actually increase the value of your home!
  • Insulating the attic can help space become more of a secure place to store your belongings and others. Without insulation, your home is more prone to weather conditions, mold, and will corrode most things that you will place in there.
  • Insulation just makes your attic look more aesthetically pleasing. Source

What To Use For Your Project

According to Home Improvement TV Host Bob Villa, these are the topic three attic insulation options for your home:

  1. Best Overall: Owens Cording R-38 Kraft Faced Fiberglass Insulation
  2. Best Bang For Your Buck: Frost King CF1 “No Itch” Natural Cotton Insulation
  3. Owens Corning R-30 Eco Touch Fiberglass Insulation. Source

How To Insulate Your Attic (With Sloped Walls)

I have taken these steps directly from a Home Improvement Magazine on how to properly insulate your attic.

  1. “Lay long, wide boards or strips of plywood across the attic floor joists to provide a walkway if the attic is not covered with flooring. Don’t skimp on walkways. It takes only a second to fall through the floor. Run extension cords to supply light as necessary.
  2. Measure the depth of the wall framing, which is the width of boards that form the attic roof structure. Choose the fiberglass blanket or batting product that will provide the R-value your house requires without exceeding the space depth; compressing insulation reduced its R-value. In warm regions, the recommended minimum is R-30 or slightly higher, while northern climates require higher values reaching near R-50. Regular fiberglass batting delivers about R-3 per inch of thickness, meaning that, used alone, it requires about a 10-inch-thick layer to deliver R-30.
  3. Measure the height of the sloped wall, from the floor to the peak. If your attic walls have more than one section angling down, like a hexagon, for example, measure each section separately and add it together to ensure accuracy. Add about 6 inches to the total height for leeway.
  4. Cut wood blocks the width of the wall framing boards — typically 16 to 24 inches — and insert on either side of, and 3 inches from, any heat-producing object. Nail through the framing into the board ends to secure. These blocks keep insulation from straying too close to the heat source and igniting.
  5. Unroll the fiberglass insulation, whether short batts or long rolls called blankets, and measure the first section’s length. Cut with a utility knife or heavy-duty scissors. Test the fit of the first piece. If satisfied, cut each piece of insulation before proceeding.
  6. Climb to the top of the wall peak, carrying one end of the insulation with you. Pull it slightly higher than the peak — perhaps a couple of inches — and bend the sides back slightly before inserting the fiberglass, the paper side facing you, between the roof framing members. Tug out on the piece slightly to fluff it once it’s situated.
  7. Pull the paper tabs over the wood framing. Staple through the paper, into the framing, with two staples on either side at the very top.
  8. Insert the next several feet, working down the wall. Secure with additional staples every 6 to 8 inches. Smooth the insulation strip as you work to avoid gaps between the paper and wood. Trim the bottom edge for length. Repeat for each wall section.
  9. Trim around openings, such as wall outlets, windows, and doorways. Cut a slit in the insulation to fit it around small obstructions. Staple the edges to wood framing where possible and stuff small gaps with the scraps from the wall strips. The exception is around heat-producing objects, such as light bulbs, some light fixtures, or metal chimneys and ducts, where fiberglass may ignite. Leave at least 3 inches of space around these items.
  10. Wrap flues and similar with heat-resistant insulation. Measure the object’s diameter, add about 6 inches, and cut mineral wool or similar fire-resistant insulation to size. Wrap around the item, overlapping the edges, and secure with insulation tape. Fill around and over lights and empty spots inside the wood blocks with excess mineral wool. Cut it slightly larger than space and insert. The snug fit creates a friction fit that holds it in place.
  11. Slit the paper facing covering the fiberglass insulation to install a layer of rigid foam insulation over the entire wall. This provides an additional R-5 per inch of thickness, approximately. While more expensive than fiberglass, it prevents thermal transfers through the roof via wood framing. If you choose to stop with the fiberglass insulation instead, tape over every seam, tear, or gap in the facing.
  12. Hang rigid foam insulation, starting at the top and working across before moving down. Push the edges tightly together and secure with roofing nails or other large-headed nails every 10 to 12 inches down each wood framing member. Large heads keep the nail head from piercing the soft foam surface. Tape each joint to ensure an air-tight application. The foam now serves as a vapor barrier instead of the paper facing.” Source

Ricky Kesler

With all of the projects I've done over the years, you'd think that I work on my house full-time. But I actually enjoy other things like spending time outdoors and time with my family.

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