Insulation Calculator

Calculate potential savings from improved home insulation. Discover how proper insulation can reduce your heating costs and improve comfort.

Insulation Savings Calculator

Calculate potential savings from home insulation

Monthly energy usage

Cost per kilowatt-hour

Total living space size

Insulation Benefits

Why proper insulation is essential for energy efficiency and comfort

Cost Savings

Reduce heating and cooling costs by up to 30%

Comfort

Maintain consistent temperature throughout your home

Environment

Reduce carbon footprint and energy consumption

Types of Insulation

Understanding different insulation materials and their applications

1

Wall Insulation

Cavity wall and solid wall insulation options

2

Loft Insulation

Most cost-effective insulation with highest savings

3

Floor Insulation

Underfloor insulation for ground floor rooms

4

Double Glazing

Window and door upgrades for heat retention

  1. 1

    Measure Areas Needing Insulation

    Calculate square metreage for: loft (length × width), walls (height × perimeter - windows/doors), basement/floor. Prioritise loft first - accounts for 25-35% of heat loss and easiest to upgrade. Building regulations require minimum 270mm loft insulation.

  2. 2

    Check Current R-Value

    Measure existing insulation thickness and identify type. Glass wool: 25mm = R-0.56, cellulose: R-0.65, spray foam: R-1.14. No insulation = R-0.18. Check loft with torch - should see at least 270mm (R-6.0). Many UK homes have inadequate 100mm (R-2.2).

  3. 3

    Determine Target R-Value

    Current UK building regulations: Loft R-6.0 to R-7.0 (270-300mm), cavity walls R-2.5 to R-3.5, solid walls R-3.0 to R-4.5 (external/internal wall insulation). Higher values reduce heating costs further but have diminishing returns above regulations.

  4. 4

    Select Insulation Type

    Choose material: Glass wool (cheapest, DIY-friendly, £15-£25/m²), blown cellulose (good for lofts, £20-£30/m²), spray foam (best performance, air sealing, £40-£60/m², professional installation). Cavity wall insulation: £15-£25/m², solid wall insulation: £85-£150/m². Consider budget and target R-value.

  5. 5

    Calculate Savings and ROI

    Calculator shows installation cost, annual energy savings, and payback period. Loft insulation typically pays back in 2-5 years through reduced heating bills. Cavity wall 3-7 years, solid wall 8-15 years. Check eligibility for ECO4 grants (free/subsidised insulation for eligible households). Factor in comfort improvements and increased property value.

Pro Tip: Use Ctrl+Enter to calculate quickly, or Ctrl+R to reset the form.

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