Sky Insulation

Spray Foam vs. Blown-In Insulation: Which Is Right for Your Home?

Choosing the right insulation type can make a big difference in your home's comfort, energy efficiency, and long-term costs. At Sky Insulation, we install both spray foam and blown-in insulation across the Denver metro area, and we often get asked: which one is better? The answer depends on your home, your goals, and your budget.

Spray Foam Insulation

Spray foam comes in two types — open-cell and closed-cell — and is applied as a liquid that expands to fill cavities, cracks, and gaps.

Pros:

  • Highest R-value per inch (R-3.7 for open-cell, R-6.5 for closed-cell)
  • Air sealing and insulation in one step — no separate vapor barrier needed with closed-cell
  • Excellent for crawl spaces, rim joists, and irregular cavities
  • Reduces moisture infiltration (closed-cell acts as a vapor barrier)

Best For:

  • Crawl spaces and basements
  • Rim joists and band boards
  • New construction or major renovations
  • Homes that need maximum energy savings

Blown-In Insulation

Blown-in insulation (fiberglass or cellulose) is machine-applied into attics, walls, and enclosed cavities. It's one of the most cost-effective ways to improve home comfort.

Pros:

  • Lower upfront cost than spray foam
  • Fast installation — an attic can be done in a few hours
  • Excellent for topping off existing insulation
  • Fills around obstacles like wiring, pipes, and framing

Best For:

  • Attic floors and open cavities
  • Wall insulation retrofits (dense-packed)
  • Budget-conscious upgrades
  • Homes that already have some insulation but need more

How to Choose

For most Denver homes, we recommend a combination approach: spray foam in the crawl space, rim joists, and any areas that need air sealing, with blown-in insulation in the attic for cost-effective coverage. This gives you the best of both worlds — maximum air sealing where it matters most, and affordable R-value where you need volume.

Get a Free Assessment

Not sure which option is right for your home? Sky Insulation offers free, no-obligation estimates. We'll inspect your current insulation, identify problem areas, and recommend the best solution for your budget and goals. Call us at (720) 691-5718 or fill out our contact form to get started.