HH Homeowner's Handbook
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TASK NO. 009 Upgrade

Add attic/duct insulation

HVAC & Air Quality
Trigger
As part of energy-efficiency upgrade
Who does it
DIY or Pro
Est. time
Half day+
Est. cost
$300-1,500
Difficulty
●●●○○
Step by step

  1. Check current insulation depth against your region's recommended R-value.

  2. Air-seal attic penetrations (can lights, plumbing stacks) before adding insulation.

  3. Choose batt, blown-in, or spray foam based on attic access and budget.

  4. Wear a respirator, gloves, and coveralls; lay boards to walk on joists safely.

  5. Layer new insulation perpendicular to existing for full coverage; leave soffit vents clear.

Questions to ask your pro
  • Are you BPI or RESNET certified, or do you have energy auditor credentials?
  • What R-value do you recommend for my climate zone, and what is my current level?
  • Will you air-seal attic penetrations before adding insulation, and is that included in the quote?
  • What insulation type do you recommend—blown-in, batt, or spray foam—and why?
  • Will you confirm soffit vents stay clear and unblocked after installation?
  • Do you check for moisture, mold, or pest issues in the attic before insulating?
  • Can I qualify for utility rebates or federal energy efficiency tax credits on this work?
Video guide
Search: 'how to insulate an attic DIY'
Watch this guide
This link is a suggested starting point and hasn't been individually re-checked recently — search the title to confirm it still matches before relying on it.
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