# Bi-Fold Floor-Track Options | Alta Vetro > Four bi-fold track options — ADA-compliant low-profile and barrier-free flat tracks with drainage integration, and when to choose each. URL: https://alta-vetro.com/guide/floor-track-options-ada-compliant-barrier-free-and-flat-tracks/ Last-Modified: 2026-07-17 ![Flush barrier-free bi-fold threshold between a kitchen and patio, seamless transition](/images/featured/flush-barrier-free-bi-fold-threshold-between-kitch.webp) ## Four Track Options, Four Applications The floor track is where a bi-fold system meets the finish floor. It carries the panel weight (on bottom-rolling systems), the guide track function (on top-hung systems), and the water-management responsibility at the threshold. The right track choice for a specific opening depends on the accessibility program, the aesthetic goal, and the exterior exposure. Alta Vetro’s bi-fold system [/bi-fold-doors/ →](/bi-fold-doors/) offers four track options. Here’s how each is applied. If you’re still deciding whether a bi-fold is the right mechanism for the opening, how bi-fold door systems work [/guide/how-bi-fold-door-systems-work/ →](/guide/how-bi-fold-door-systems-work/) covers the fold-and-stack action that shapes these track decisions. ## Standard Sill Track The standard sill is a raised threshold profile that carries the panel weight (bottom-rolling) or acts as a guide (top-hung). Height is typically 25-40mm above the finish floor. **Best for:** Interior bi-fold applications where accessibility isn’t a driver — a bi-fold room divider, an interior office partition, or an exterior application where the raised threshold is compatible with the exterior finish detail. **Trade-offs:** The raised profile creates a visible sill line and a step at the threshold. Not appropriate for barrier-free or ADA-compliant applications. ## Low-Profile ADA-Compliant Track The low-profile track reduces the visible sill to roughly 12mm above the finish floor — within the ADA-compliant maximum threshold height (1/2 inch, or roughly 13mm). The track is still slightly raised, but it accepts wheeled mobility and meets the accessible-route threshold requirement. Integrated threshold drainage runs under this track profile — driven water at the sill is caught by the drainage channel and routed out. **Best for:** ADA-required exterior applications, aging-in-place private residential specifications, or commercial installations with accessibility program requirements. **Trade-offs:** The visible sill line is still present, though minimized. Requires slightly more sill construction depth than a barrier-free flat track. ![Macro of a low-profile ADA-compliant bi-fold track with drainage](/images/content/macro-of-low-profile-ada-compliant-bi-fold-track-w.webp) ## Barrier-Free Flat Track The flat track sits at the finish-floor level — no visible raised sill. The interior finish floor and exterior patio surface are at the same level, and the track is set flush with both. Full integrated drainage under the flat track. On Colorado mountain installations, the drainage handles snowmelt and driven water at the threshold. The flush sills and barrier-free thresholds guide [/guide/flush-sills-and-barrier-free-thresholds-for-indoor-outdoor-living/ →](/guide/flush-sills-and-barrier-free-thresholds-for-indoor-outdoor-living/) covers the drainage integration in detail. **Best for:** Modernist and contemporary residential specifications where the flush indoor-outdoor transition is a design driver. Applications where daily indoor-outdoor traffic is high and the barrier-free level is genuinely used (not just aesthetic). **Trade-offs:** Requires the most careful construction coordination — slab block-out for the track recess, waterproofing membrane tie-in, finish floor coordination to the track level. ## Raised Protective Threshold The raised protective threshold is a higher profile — typically 50-75mm above finish floor — designed for exposed sites where wind-driven water, heavy snow, or unusual exposure conditions require additional protection at the threshold. **Best for:** High-exposure Colorado sites (extreme wind, deep drifting snow, box-canyon locations) where the standard sill or low-profile track might not provide the water-management margin the site requires. Occasionally specified on exposed mountain applications where the design accepts the taller threshold in exchange for protection. **Trade-offs:** The tallest visible sill line. Requires a definite step at the threshold, which affects daily use and is not ADA-compliant. ## How to Choose The choice starts with the accessibility program. If ADA compliance is required, the low-profile or barrier-free flat track are the options. If barrier-free level is the design goal, the flat track is the answer. From there, exterior exposure informs the sub-choice. Most Colorado mountain applications with reasonable roof-overhang protection can use the flat track with confidence — the integrated drainage handles the exposure. On extremely exposed installations, the raised protective threshold may be worth considering. The flush thresholds guide [/guide/flush-sills-and-barrier-free-thresholds-for-indoor-outdoor-living/ →](/guide/flush-sills-and-barrier-free-thresholds-for-indoor-outdoor-living/) covers the flat-track detail specifically. The bi-fold hub [/bi-fold-doors/ →](/bi-fold-doors/) covers the full product line context. ## Coordination Notes Whichever track is specified, the coordination during construction includes: - **Slab preparation** to accept the track profile - **Waterproofing membrane tie-in** to the drainage channel - **Finish floor coordination** to the track level (especially on flat-track installations) - **Exterior grade slope** away from the threshold (1/4 inch per foot minimum for the first two feet) The design consultation walks through the track choice and the associated construction coordination for the specific opening. FAQ ## Related Questions ### How many track options are there? Four floor-track options across the bi-fold line: standard sill, low-profile ADA-compliant, barrier-free flat, and raised protective threshold. Each fits a specific installation context — accessibility, flush design, or exposed-site protection. ### Can the track be flush? Yes. The barrier-free flat track sits at the finish-floor level, creating a fully flush indoor-outdoor transition. Integrated drainage under the track manages water without a raised threshold. ### How is drainage handled? Every track option except the standard interior installation includes integrated threshold drainage. The drainage channel routes water away from the seal line before it can enter the assembly, and discharges to daylight or a subsurface drainage system. Continue Reading ## Related Guides comparison ### Bi-Fold Folding Walls vs. Sliding Systems for Your Opening Weigh bi-fold against sliding for your opening — full-open clearance vs minimal sightlines, stacking, thermal and cost differences, and ideal openings. [Bi-Fold Folding Walls vs. Sliding Systems for Your Opening →](/guide/bi-fold-folding-walls-vs-sliding-systems-for-your-opening/) concern ### Bi-Fold Performance Ratings for Demanding Applications (CW-PG55) The performance credibility to spec bi-folds on demanding projects — CW-PG55, wind load to 5,000 Pa, water tightness to 600 Pa, air tightness, hurricane pin option. [Bi-Fold Performance Ratings for Demanding Applications (CW-PG55) →](/guide/bi-fold-performance-ratings-for-demanding-applications-cw-pg55/) definition ### How Bi-Fold Door Systems Work (Thermal, Tracks, Screens) Bi-fold mechanics explained — folding panel operation, top-hung and bottom-rolling systems, thermal insulation, and track and screen integration. [How Bi-Fold Door Systems Work (Thermal, Tracks, Screens) →](/guide/how-bi-fold-door-systems-work/) The Collection ## Learn more about Folding / Bi-Fold Door Systems Explore the full product line and request a design consultation to translate this reading into a specification for your project. Explore Folding / Bi-Fold Door Systems [/bi-fold-doors/ →](/bi-fold-doors/) Request a Consultation [/contact/ →](/contact/)