What is Thermal / heat insulation?
A foam or coated backing that slows heat transfer through glass.
Short answer
'Thermal' printed on the pack with no coating visible on the back is marketing.
Thermal / heat insulation when buying a curtains & blinds
A foam or coated backing that slows heat transfer through glass.
Why it matters: On a west or south-facing window this measurably reduces AC load in the afternoon.
Look for: 'Thermal' printed on the pack with no coating visible on the back is marketing.
Full Curtains & Blinds buying guide