Building & renovation

How many spray cans for radiators?

How many 400 ml spray cans to repaint radiators — from total m², coats and coverage per can.

Quick answer

Radiator enamel in aerosol covers far less wall area than you expect — fins, valves and overspray mean **~1–2 m² per 400 ml can per coat**. Default **1.5 m²/can**, **2 coats**, 10% waste. Example: double panel radiator **2.5 m²** → 2.5 × 2 ÷ 1.5 × 1.1 ≈ **3.7** → **4 cans**.

Advanced settings

Spray cans needed

4 × 400 ml

Radiator spray paintAmazon →Affiliate link

Radiator enamel sprays cover less area than wall paint — fins, valves and overspray eat product. A 400 ml can often does 1–2 m² per coat on a typical panel radiator. Ventilate well; heat the room only after full cure per label.

How it works

Measure the actual metal surface (both sides if you paint behind), not the wall footprint. Heat-resistant formulas need full cure before switching heating back on — check the can label.

Frequently asked questions

How do I estimate radiator m²?+

Count flat panels and columns you will coat — a typical double convector 100×60 cm is roughly 2–3 m² including edges. Add all radiators in the room for a batch repaint.

One or two coats?+

Bare metal or colour change: two coats standard. Refresh over sound same-colour enamel: one coat may suffice — set coats to 1 in advanced.

Do I need to sand radiators first?+

Remove loose rust and gloss on failing paint — keying the surface improves adhesion more than buying extra cans. This tool sizes paint quantity only, not prep materials.

Spray vs brush for radiators?+

Spray reaches between fins faster; brush + radiator roller avoids overspray on walls but uses similar litres. Coverage per can in this calculator assumes aerosol application.

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