Compare heat pump footprint, side by side

See how much ground space and clearance the top 3 brands actually need before you commit.

Compare heat pump footprint, side by side

See how much ground space and clearance the top 3 brands actually need before you commit.

Comparing the top 3 heat pump brands

This page compares the top 3 heat pump brands: Octopus Energy, Vaillant, and Aira. It looks at their size, noise, and footprint side by side, so you can see how they stack up before speaking to an installer.

Octopus Energy

Vaillant

Aira

How much space it actually needs

Solid shape is the unit's actual footprint (width × depth). The dashed, tinted outline is the operational clearance that brand needs to breathe properly. One representative footprint is shown per brand — footprint barely changes across a brand's size range. It's height that grows with output instead (see the Size Comparison tool for that). Clearance genuinely does differ by brand, sourced from each manufacturer's own guidance where available.

Octopus Cosy
Octopus's own guidance: roughly 1m in front and to each side. Rear figure not explicitly published by Octopus, shown here as a cautious placeholder.
  • Footprint is 855 × 595mm across all three models (Cosy 6, 9, and 12)
  • The range only gets taller, not wider or deeper
front clearance
Any Cosy model
855 × 595mm footprint
~2.9m × 1.9m with clearance
Vaillant aroTHERM plus
Based on Vaillant's own installation manual clearance table (minimum clearances for heating mode).
  • Footprint is 1,100 × 450mm across all five models (3.5kW through 12kW)
  • Only height changes across the range
front clearance
Any aroTHERM plus model
1100 × 450mm footprint
~1.7m × 2.0m with clearance
Aira *estimated
Aira's own manual says the front, back and sides must be unobstructed, but doesn't publish an exact distance in metres or millimetres. The figures shown here are a general estimate, not an Aira-published spec, always confirm the real number with your installer.
  • Close to identical for the 6kW and 8kW (1,216 × 425mm)
  • The 12kW is only slightly different (1,152 × 416mm)
  • Height is what changes most
front clearance
6kW / 8kW model
1216 × 425mm footprint
~2.4m × 1.9m with clearance*
How much of your garden is that, really?
The average UK garden is about 244m² — roughly nine tenths of a tennis court. Here's each brand's clearance zone drawn at the same scale, sitting where most people actually site one: near the back of the house.
Octopus Cosy — ~2.2% of the garden
Vaillant aroTHERM plus — ~1.4% of the garden
Aira — ~1.9% of the garden

Clearance figures are sourced from each brand's own installation guidance where published (see the note under each brand above). Exact requirements can vary between specific models within a range, and your installer's site design always takes precedence. This is a footprint and depth view only — it doesn't show the unit's height. Separately, in England, current Permitted Development Rights allow units as close as 1m to your property boundary. That's a planning rule, not a brand's own clearance requirement, so both apply together.

Frequently asked questions

Do I need planning permission for a heat pump?

What changed with Permitted Development Rights?

What about Wales?

Are there exceptions?

Just Ask: Heatpump

Just Ask: Heatpump is an independent companion to Visit a Heat Pump and Get a Heat Pump. Built from real installation experience to give honest, practical guidance before you commit.