Heat pump awareness campaign · April 2025

Don't lose the heat
you've already paid for

Wet or damaged pipe insulation can cost heat pump households around £43 a year, often without any obvious signs. Check yours in five minutes and get a free expert review.

5% Typical heat loss from wet insulation
£43 Extra annual running cost per household
£770 Over an 18-year heat pump lifetime
Expert support

This campaign is backed by qualified HVACR assessment experts and the Thermal Insulators Contractors Association (TICA) good practice guidance for domestic heat pump pipework insulation.

Read the TICA white paper →
1

Check your external pipework

Go outside and look at the pipes running from your heat pump. Tick each item you can confirm.

Insulation is continuous with no gaps, splits or missing sections

Even a short gap causes disproportionate heat loss at lower flow temperatures

Outer surface is dry and firm with no soft, spongy or damp patches

Wet insulation conducts heat away rather than retaining it (this is the most common issue)

No visible cracking, crumbling or UV degradation on the surface

Many foam types degrade in sunlight within 2–3 years if left unprotected

Joints, bends and T-junctions are covered as well as joints and bends

Elbows and connections are often skipped during installation and are a major source of loss

Insulation is adequately thick, not a thin wrap that compresses flat when squeezed

TICA guidance specifies minimum thickness by pipe diameter ; compressed insulation performs like no insulation

Where pipework enters the wall, insulation runs flush with no bare pipe visible at the penetration

A short exposed section at the wall entry point can account for a significant proportion of total losses

0 of 6 checked

2

Send photos for a free expert review

Our qualified experts will review your pipework photos and email you clear, jargon-free feedback within 3 working days.

Reviewed by qualified HVACR experts

Assessed against TICA good practice guidance for domestic heat pump pipework

Your photos
JPEG or PNG only Max 8MB per photo Up to 4 photos External pipework only

Tap to add photos

Or drag and drop. A photo of the outdoor unit pipework works best

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Why does this matter?

Heat pumps run at lower flow temperatures than traditional boilers, which makes them more sensitive to distribution losses before heat reaches the room. Where pipework insulation has degraded, or never installed correctly, systems must work harder to maintain comfort.

This is not a heat pump technology problem. It is an installation and maintenance issue that can be fixed.

Expert analysis consistently shows that heat pumps are highly efficient systems, but only when the heat they generate actually reaches the space it is intended to heat. Avoidable losses through poorly insulated pipework are a simple issue with a real impact on running costs and comfort.

Needs attention
Heat pump pipework in good condition, showing complete, dry insulation with no gaps
Good condition

Continuous, dry insulation with no gaps or damage. Heat stays in the pipes where it belongs.

Estimated annual impact of a 5% pipework heat loss, by COP

COP Extra electricity (kWh/yr) Extra cost (£/yr) Extra emissions (kgCO₂e/yr)
2.5 208 £51 37
3.0 173 £43 31
4.0 130 £32 23

Based on current Ofgem benchmark consumption and price-cap figures, and the UK government electricity conversion factor.