Day 9: Install insulation under your floorboards (above the ceiling)

According to Forbes installiung insulation under your floorboards could reduce your energy bill by around 10%

If you’ve got some spare time on your hands you could save yourself hundreds of pounds per year and add value to your house by lifting your floorboards (or removing your ceiling) and installing insulation.

Installing insulation between your ceiling and floor boards can help improve energy efficiency and reduce noise transmission between different levels of your home. Here’s a step-by-step guide to help you install insulation in this area:

Materials and Tools You’ll Need:

  • Insulation material (such as fiberglass batts, mineral wool, or foam board)
  • Utility knife
  • Measuring tape
  • Safety goggles
  • Dust mask
  • Gloves
  • Long-sleeved shirt and pants
  • Staple gun or insulation supports (to hold the insulation in place)
  • Caulk or foam sealant (for sealing gaps and cracks)
  • Protective covering for the floor and furniture (to catch falling debris)


**1. ** Safety Precautions:

  • Put on your safety gear: goggles, dust mask, and gloves.
  • Cover the floor and furniture in the area where you’ll be working to catch any debris.

**2. ** Measure and Cut:

  • Measure the distance between the ceiling joists or floor joists.
  • Use a utility knife to cut the insulation material to fit the measured space. Make sure it fits snugly without any gaps.

**3. ** Install the Insulation:

  • Insert the insulation material between the ceiling or floor joists. If you’re using fiberglass batts, be careful not to compress them too much, as this reduces their effectiveness.
  • Use a staple gun or insulation supports to hold the insulation in place. Staple the facing of the insulation to the sides of the joists to prevent it from sagging over time.

**4. ** Seal Gaps and Cracks:

  • Inspect the area for any gaps or cracks around pipes, electrical wiring, or other penetrations in the ceiling or floor.
  • Use caulk or foam sealant to seal these gaps and cracks. This helps in preventing air leakage, which can significantly impact the insulation’s effectiveness.

**5. ** Safety Check:

  • Double-check for any exposed wires or other potential hazards that the insulation might cover. Ensure everything is properly insulated and sealed.

**6. ** Clean Up:

  • Clean up the area, removing any excess insulation material or debris.

**7. ** Dispose of Waste:

  • Dispose of any waste material properly, following local regulations.


  • Safety First: Always wear appropriate safety gear, especially when dealing with insulation materials, as they can irritate the skin and respiratory system.
  • Proper Fit: Ensure the insulation fits tightly between the joists without any gaps or spaces. This ensures maximum effectiveness.
  • Sealing: Properly sealing gaps and cracks is crucial for maintaining the insulation’s efficiency. Air leaks can significantly reduce the insulation’s effectiveness.

If you’re unsure about any step of the process, or if you’re dealing with a complex insulation scenario, it’s a good idea to consult with a professional or hire a contractor to ensure the job is done correctly and safely.


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