Calculator – Arrow Energy Solutions

🔥 Insulation Calculator

Work out your U-values and see how much you could save

Calculated U-Value

—

W/m²K

Select options below

Outer Leaf

Material

Cavity

Cavity Width

🟦

Climabead CWI

λ = 0.033 W/mK (full cavity fill)

Inner Leaf

Material Internal plaster finish

Building Regs Reference Targets

New build (Part L 2021)≤ 0.18 W/m²K

Existing dwelling retrofit≤ 0.30 W/m²K

Typical pre-insulation wall~1.0–1.6 W/m²K

Calculated U-Value

—

W/m²K

Select options below

Insulation

Material Total insulation depth

Account for timber joist thermal bridging
~8% of ceiling area taken up by joists (realistic)

Ceiling Finish

Plasterboard thickness

Building Regs Reference Targets

New build (Part L 2021)≤ 0.15 W/m²K

Retrofit / top-up target≤ 0.16 W/m²K

Uninsulated loft (typical)~2.0–2.3 W/m²K

Estimated Annual Savings

You could save about £— every year

Energy saved

—

kWh / year

Bill reduction

£—

per year

CO₂ saved

—

kg / year

What are you insulating?

Property Size

Select your property type

External wall area (m²)

Thermal Performance

Current U-value

After insulation

Heating Fuel

How do you heat your home?

Ready to start saving?

Get a free, no-obligation quote from our accredited installers.
PAS 2030:2023 compliant · TrustMark registered · Covering the South of England.

Get My Free Quote →

Indicative calculations using ISO 6946 method. Savings estimates use UK Ofgem price cap (April–June 2026) and heating degree days of 2,100 (UK average, base 15.5°C). Actual figures vary with construction, occupancy, and local climate. For certified figures, contact us for a survey.

🔥 Insulation Calculator

Use our Insulation Calculator to work out your U-values or to see how much you could save.

Calculated U-Value

—

W/m²K

Select options below

Outer Leaf

Material

Cavity

Cavity Width

🟦

Climabead CWI

λ = 0.033 W/mK (full cavity fill)

Inner Leaf

Material

Internal plaster finish

Building Regs Reference Targets

New build (Part L 2021)≤ 0.18 W/m²K

Existing dwelling retrofit≤ 0.30 W/m²K

Typical pre-insulation wall~1.0–1.6 W/m²K

Calculated U-Value

—

W/m²K

Select options below

Insulation

Material

Total insulation depth

Account for timber joist thermal bridging
~8% of ceiling area taken up by joists (realistic)

Ceiling Finish

Plasterboard thickness

Building Regs Reference Targets

New build (Part L 2021)≤ 0.15 W/m²K

Retrofit / top-up target≤ 0.16 W/m²K

Uninsulated loft (typical)~2.0–2.3 W/m²K

Estimated Annual Savings

You could save about £— every year

Energy saved

—

kWh / year

Bill reduction

£—

per year

CO₂ saved

—

kg / year

What are you insulating?

Property Size

Select your property type

External wall area (m²)

Thermal Performance

Current U-value

After insulation

Heating Fuel

How do you heat your home?

Ready to start saving?

Get a free, no-obligation quote from our accredited installers.
PAS 2030:2023 compliant · TrustMark registered · Covering the South of England.

Get My Free Quote →

Indicative calculations using ISO 6946 method. Savings estimates use UK Ofgem price cap
(April–June 2026) and heating degree days of 2,100 (UK average, base 15.5°C).
Actual figures vary with construction, occupancy, and local climate. For certified figures, contact us for a survey.