The live folding glass walls Florida page notes that threshold and weather sealing at the bottom track are among the most failure-prone elements and calls for proper drainage and continuous gaskets. This article goes deeper on flush-threshold coordination. It is not a product landing page and not legal advice.
Why thresholds fail restaurants
Operable glass walls sit where three packages meet: Division 08 system sill, concrete or deck waterproofing, and interior / exterior floor finishes. If any one of those packages is drawn in isolation, the field invents a detail. Invented sill details leak, trip, or both.
Common restaurant failure modes:
- Track that holds water because the drain path was never daylighted
- Interior tile or wood that dies into the sill without a waterproof lap
- Exterior pavers set flat or reverse-sloped toward the opening
- Flush aesthetic intent with no accessible change-in-level strategy documented
- Late substitution of a raised sill after furniture and millwork are already bought
Accessibility process (not a legal ruling)
Whether a specific sill is accessible under the ADA Standards, Florida Accessibility Code, or local amendments is project-specific [UNCERTAIN]. This section is a coordination process, not a compliance certificate.
- State the design intent in writing: flush, low-profile, or raised sill with bevel strategy.
- Pull the manufacturer sill detail for the exact configuration (folding, multi-slide, pocketing, top-hung vs floor-supported).
- Have the architect mark change-in-level, bevel, and clear floor space assumptions on the enlarged sill detail.
- Confirm operating hardware and force assumptions with the manufacturer literature for that system.
- Route the enlarged detail through the project accessibility reviewer or consultant if the contract requires one.
- Do not fabricate until the sill detail is Approved or Approved as Noted.
Top-hung systems can reduce the height of a floor track, but they do not erase the need for a weather and transition detail at the panel base. Floor-supported systems put more structure in the sill and need even earlier concrete / waterproofing coordination.
Drainage path
Florida wind-driven rain and restaurant wash-down are not theoretical. Water that enters the sill must have somewhere to go that is not the dining room.
- Identify the sill pan or manufacturer drainage channel on the shop drawing.
- Show where weep / drain outlets daylight (to exterior grade, deck drain, or other designed receiver).
- Keep interior finishes from damming the drain path.
- Coordinate sealant joints and gasket continuity at jambs so water cannot bypass the pan ends.
- Ask who pressure-washes the patio and how that water hits the sill.
Live ACG multi-slide / bifold contractor language emphasizes that drainage is central on these systems and that sill pan, drainage path, and threshold-to-interior-floor transition belong in shop drawings. Treat that as process guidance, then verify on the project manufacturer details.
Floor and finish coordination
Draw a single enlarged section that includes:
- Structural slab or deck
- Waterproofing / pan / membrane owner
- Operable wall sill / track / threshold
- Interior finish thickness and termination
- Exterior finish thickness, slope, and joint
- Any recessed mat, trench drain, or expansion joint nearby
If the interior finish thickness changes after shops are approved, the flush condition usually breaks. Freeze finish thicknesses before fabrication release whenever possible.
Detail coordination checklist
TEMPLATE ONLY. Coordination checklist. Not a code opinion. Not a project record.
| Item | Ready? | Notes |
|---|---|---|
| System type and sill detail ID | Y / N | Folding / multi-slide / pocket; manufacturer detail number |
| Flush vs raised design intent written | Y / N | Architect note on enlarged section |
| Accessibility review path assigned | Y / N | Project-specific ADA / code reviewer |
| Sill pan / weep daylight shown | Y / N | Receiver and slope confirmed |
| Interior finish thickness frozen | Y / N | Tile / wood / concrete polish thickness |
| Exterior finish slope away from sill | Y / N | Pavers / deck / trench drain |
| Waterproofing trade owner named | Y / N | Who installs membrane / pan transitions |
| Shop drawing Approved / AAN | Y / N | No fabrication on verbal sill changes |
| Field mock / first-bay review scheduled | Y / N | Before full run of openings |
Trade roles template
Typical Florida GC practice only. Confirm against the subcontract and Division 01.
- Architect / designer: flush intent, finish package, enlarged sill section, accessibility design intent.
- Structural / EOR: header and any slab edge conditions that affect sill anchorage.
- GC: concrete, waterproofing, and finish trade sequencing; protection of the sill during other trades.
- Glazing sub: system sill / track / pan detailing per manufacturer and approved shops; install tolerances; gasket and sealant at the operable wall.
- Waterproofing / finishes: membrane laps, exterior slope, interior termination.
How to ask for the right scope
Send elevations, the opening schedule, and the enlarged sill / floor transition detail (even if it is still schematic). Add one line: material-only or furnish-and-install. If flush accessibility is required, say so in the RFQ so the system family is not bid with an incompatible raised sill.
ACG works from West Palm Beach, Naples, and Tampa. Call (772) 486-7711. FL CGC #1531993.
Frequently Asked Questions
What is a flush glass-wall threshold?
A flush threshold is a sill condition designed so the interior floor, operable glass-wall sill, and exterior finish meet with minimal change in level, while still managing water. Exact profile depends on the manufacturer system and the architect floor package.
Are flush thresholds automatically ADA compliant?
No. Accessibility compliance is project-specific. Flush intent helps, but change-in-level limits, bevels, operating force, and clearances must be confirmed against the applicable standards and the AHJ path for that project. Compliance remains [UNCERTAIN] until reviewed on the project documents.
What usually fails first on Florida restaurant sills?
Drainage path and floor-finish coordination. Water that cannot leave the sill track, or interior finishes that terminate without a waterproof lap, create the recurring service calls.
Who owns the threshold detail on a bid?
Assign it early. Architect owns design intent. Glazing sub owns system sill / pan detailing per approved shops. GC coordinates concrete, waterproofing, and finish trades. Exact contract assignment is project-specific.