Flush thresholds reduce upstands but reduce passive water defence.
TREVIK · THRESHOLDS
Threshold and drainage design for large architectural openings.
The cleanest visual threshold can be the hardest detail to make weather-resistant. Floor levels, drains, sill geometry and accessibility must be resolved together.
SHORT ANSWER
Design the floor and water path before freezing the door.
Coordinate internal finished floor, external paving, sill/track depth, drainage channel, falls, waterproofing, accessible route and maintenance access as one section. Then choose the opening system that can work within that detail.
KEY PROJECT POINTS
What should drive the decision.
These are project inputs, not substitute engineering or automatic product approvals.
External falls should move water away from the opening.
Tracks need cleaning and drainage access.
Door pocket/stack zones can interrupt drainage paths.
Accessibility requirements may constrain sill height.
Wind-driven rain can exceed simple gravity drainage assumptions.
Draw one critical section
A section through internal floor, sill/track, external paving and drain exposes conflicts that plan drawings often hide.
Separate surface water and door drainage
Large terrace/paving flows should not be expected to discharge through the door's small track/weep system.
Protect accessibility
Threshold height, drainage grates, transitions and slip resistance should be coordinated with local accessibility requirements.
Make it maintainable
Leaves, sand, hair and debris can block tracks and drains. Cleaning access belongs in the design.
PROJECT INPUTS
What to have ready before asking for the exact system.
A stronger brief shortens the gap between product interest and a useful technical/commercial response.
Internal FFL
External paving level
External falls
Sill/track depth
Drain type/location
Waterproofing
Accessible route
Door stack/pocket
Wind-driven rain exposure
Canopy/overhang
Cleaning access
Local envelope detail
EVIDENCE BOUNDARY
The door supplier controls the sill; the project team controls the surrounding water management.
Use exact sill/track drawings and tested water-performance information as inputs, then coordinate site drainage, membranes, thresholds and external levels with the appointed designer.
FAQ
Questions project teams usually need answered.
Is a completely flush threshold always possible?
Not in every exposure/system. It depends on the exact sill, drainage, water performance and local accessibility/weather requirements.
Can paving drain into the door track?
It should not be assumed. Site drainage should manage bulk surface water independently.
Why do tracks need maintenance access?
Debris can obstruct rollers, weeps and drainage paths, reducing operation and weather performance.