A standard track lift needs roughly 300 to 350 mm of headroom above the opening, plus about 100 to 150 mm of side room on each side. Low-headroom track kits can work with around 150 to 200 mm, and these figures vary by manufacturer and model.
Headroom is measured from the top of the opening to the nearest obstruction such as a beam, pipe or light fitting. If space is very tight, a rolling shutter may suit better. A survey confirms the exact figure before you order an automatic sectional garage door.