Check the clear opening
The total glazed width is not the same as the opening width. Compare panel count, sliding direction, operation and threshold before choosing.
Match the doors to everyday use
Consider the terrace, insect screens, curtains and routes through the living room. Ask about glazing and floor and wall connections.
Operation and interior space in daily use
Try the operation on a comparable door system. Check handle height, effort and threshold. Ask which panel slides and where the fixed glass remains. Include curtains, insect screens and furniture in the plan. A wide opening must suit the facade structure and remaining side sections; have these assessed together before fixing dimensions.
Choose the sliding direction from your route
Place the opening where you actually walk outside. Fixed glazing behind a sofa may work well while access is needed near the kitchen. Include terrace furniture. Ask how the track is cleaned and threshold rainwater drains. A low threshold needs suitable detailing inside and outside.