What Is a Floor Spring? A Selection Guide for Glass Doors and Heavy-Duty Entrances

20 2026.05
What Is a Floor Spring? A Selection Guide for Glass Doors and Heavy-Duty Entrances

What Is a Floor Spring? A Selection Guide for Glass Doors and Heavy-Duty Entrances

When specifying door hardware for commercial buildings, hotel lobbies, glass storefronts, or high-traffic public entrances, selecting the right concealed door closer is one of the most consequential decisions in the project. A floor spring is embedded in the floor, bearing the full structural weight of the door panel while controlling opening and closing speed through an integrated hydraulic mechanism — completely out of sight, with no impact on door clearance or interior aesthetics.

Incorrect selection leads to predictable problems: door panels sagging or misaligning, hydraulic mechanisms failing under sustained load, and higher long-term maintenance costs. This guide covers what a floor spring is, which door types it suits, how to evaluate load capacity, and how to avoid the most common specification errors. For door-type references, see our pages for Aluminium Doors, Glass Doors, Steel-Encased Wooden Doors, and Wooden Doors.

Quick Summary

  • Floor springs are the standard door control solution for glass doors, heavy doors, and commercial entrances.
  • Selection should consider door weight, door width, usage frequency, and floor installation conditions.
  • Heavy-duty entrances typically require a higher load-capacity model with industrial-grade hydraulics.
  • Narrow-type floor springs are available for installations with limited floor box depth.

Quick Model Recommendation

  • S200: Standard commercial aluminium doors and office entrance doors.
  • S275: Narrow installation spaces and mid-to-large glass doors where floor box depth is limited.
  • S280: Heavy-duty commercial entrances, large glass doors, hotel lobbies, and high-traffic public facilities.

1. What Is a Floor Spring?

A floor spring is a door control hardware component installed beneath the floor surface. Unlike surface-mounted closers, it is completely concealed within a floor box — making it the preferred door hardware system for glass storefronts, hotel lobbies, office building entrances, and high-end commercial interiors where aesthetics and clear floor access matter.

The door panel pivots on the floor spring's central axis, with the door's full weight transferred to the floor structure below. The integrated hydraulic mechanism controls closing speed, prevents slamming, and in commercial-grade models provides a hold-open position at a fixed angle. Key advantages include high load capacity, concealed installation, precise hydraulic control, and compatibility with frameless glass door designs that cannot accommodate surface-mounted hardware.

2. Floor Spring vs. Transom Closer

Both control door closing, but differ significantly in installation position, load capacity, and compatible door types:

Floor Spring

  • Installation: Embedded in the floor — fully concealed
  • Primary Function: Bears full door weight + controls closing speed
  • Load Capacity: High — 80 kg to 300 kg and above
  • Best For: Glass doors, heavy doors, frameless doors, high-traffic commercial entrances
  • Installation Requirement: Floor box pre-embedding required — confirm before floor construction

Transom Closer (Overhead Closer)

  • Installation: Mounted above the door frame — no floor work required
  • Primary Function: Positioning support + closing speed control
  • Load Capacity: Moderate — up to approximately 100 kg
  • Best For: Aluminium doors, wooden doors, interior office doors, retrofit projects
  • Installation Requirement: No floor excavation needed — simpler installation

→ See also: Transom Closer vs. Floor Spring — Complete Selection Guide

3. Door Type Applications

Different door types have different load, structural, and installation requirements. The following covers compatibility and selection priorities for each common application.

Glass Door

Compatibility: Full-glass and frameless glass doors are the primary application. Panels 12 mm thick and above typically exceed 100 kg — a verified load-capacity specification is essential. The most common application for retail storefronts, hotel entrances, and corporate lobbies.

Selection Priority: Confirm door weight and door width together. For high-traffic glass entrances, specify an industrial-grade model with adequate hydraulic durability.

→ Recommended: S275 / S280　｜　Glass Door Application Page

Aluminium Door

Compatibility: Standard aluminium doors may suit either a floor spring or a transom closer. Frameless aluminium doors, wide double-leaf configurations, and high-frequency commercial aluminium entrances are best specified with a floor spring for long-term stability.

Selection Priority: Confirm door weight, width, and daily usage. Wide panels require torque verification.

→ Recommended: S200 / S220 / S275　｜　Aluminium Door Application Page

Heavy Door

Compatibility: Fire-rated doors, steel-encased wooden doors, and other heavy-duty panels — often exceeding 150 kg — are the core application for high load-capacity specifications. Common in hospitals, government buildings, hotels, and industrial facilities.

Selection Priority: Door width torque must be verified alongside static weight. Specify a model with a rated capacity that provides adequate safety margin.

→ Recommended: S280　｜　Steel-Encased Wooden Door Application Page

Commercial Entrance — Hotel, Mall, Office Building

Compatibility: Shopping malls, hotel lobbies, bank branches, and office building main entrances require a door hardware system capable of sustaining hundreds of cycles per day without performance degradation. Durability and consistent hydraulic control are the primary requirements.

Selection Priority: Specify an industrial-grade model with a rated service life that matches the project's operational demands.

→ Recommended: S275 / S280　｜　Application Areas Overview

Double Action Door

Compatibility: Restaurant kitchen doors, hospital corridor doors, and service entrances requiring two-way passage need a double action floor spring that supports opening in both directions with controlled hydraulic return on each side.

→ Recommended: S200 / S220　｜　Floor Spring Accessories

4. Load Capacity: How to Read the Specification

Rated load capacity (kg) is the primary selection parameter — but relying on door weight alone is one of the most common and costly errors in door hardware procurement. Three factors must be evaluated together:

① Static Door Weight (kg)

Always obtain the verified weight from the door panel manufacturer — particularly for glass doors where panel weight varies significantly by thickness and dimensions.

② Door Width (Torque Calculation)

The wider the panel, the greater the torque on the pivot axis. A 100 kg door at 900 mm width places a significantly different real-world load on the floor spring than the same door at 1,200 mm. For wide panels — common in hotel entrances and mall storefronts — always provide door width to the supplier for torque verification before finalising the specification.

③ Usage Frequency

High-frequency environments require a rated capacity with a meaningful margin above actual door load. Operating consistently near the rated limit accelerates hydraulic wear and shortens service life.

5. CHIEN CHIN Floor Spring Models

CHIEN CHIN — a Taiwan-based door hardware manufacturer and floor spring supplier serving India, the Middle East, and global B2B markets — offers a complete range from light-duty to heavy-duty specifications:

S200 Floor Spring　｜　Light to Medium Duty

Suitable for standard commercial aluminium doors and office entrance doors. Supports single and double-action configurations — the most widely specified entry-level model in the CHIEN CHIN range.

S220 Floor Spring　｜　Medium Duty

Higher load capacity than the S200 — suitable for mid-sized commercial doors with higher usage frequency and lighter glass door configurations.

Floor Spring 275 — Narrow Type　｜　Space-Constrained / Glass Doors

Narrow floor box design for installations with limited depth or shallow frame conditions. EN 1154 certified — a practical choice for retrofit projects and glass door applications where standard floor box depth is unavailable.

S280 Heavy-Duty Floor Spring　｜　Heavy Doors / High-Traffic Entrances

CHIEN CHIN's highest-capacity model — designed for large glass doors, heavy door panels, department store entrances, hotel lobbies, and high-traffic public facilities. EN 1154 certified, with hydraulic durability engineered for sustained commercial and institutional use.

→ Full product range: Floor Spring Products Overview　｜　Floor Spring Accessories

6. International Certifications and Commercial Standards

CHIEN CHIN floor springs comply with EN 1154 European door closer standards, covering durability, closing speed control, and safety performance across commercial-grade usage cycles. The S275 and S280 models carry EN 1154 certification — providing the compliance documentation required for project specification submissions, OEM partnerships, and market entry across India, the Middle East, and international projects.

  • EN 1154 — European Standard for Door Closers: S200 / S275 / S280
  • UL 228 — U.S. Safety Standard: Transom Closer T500E
  • SGS — Third-Party Test Reports: Door control hardware series
  • ISO 9001 — Quality Management System: Full product line
  • BIS IS 6315 — India Standard Certification: Door control hardware series

→ View Full Certifications Overview

7. How to Choose a Floor Spring: 3-Step Process

Step 1 | Confirm Door Panel Data

  • Door material (glass / aluminium / steel-encased wood) and panel thickness
  • Door dimensions: width (mm) × height (mm)
  • Verified door panel weight (kg) — obtain from door manufacturer
  • Single-action or double-action opening requirement
  • Estimated daily opening and closing cycles

Step 2 | Confirm Floor Installation Conditions

  • Floor type (concrete / raised timber / tile) and available installation depth
  • Verify floor thickness is sufficient for the floor box
  • Timing: floor spring pre-embedding should be completed before floor finishing
  • For retrofit projects: assess excavation feasibility and confirm structural support

Step 3 | Submit Data for Specification Confirmation

  • Provide door weight + door width for torque calculation
  • Describe the project type (mall / hotel / office / public facility)
  • Confirm floor box dimensions and accessory requirements
  • For OEM or bulk procurement: provide specifications and quantities

8. Common Specification Mistakes

  • Selecting by door weight alone, ignoring door width torque
    Panels wider than 1,000 mm can exceed the floor spring's actual load tolerance even when static weight appears within spec. Always provide door width for torque verification.
  • Insufficient floor box installation depth
    Thin floor slabs or raised floor systems that cannot accommodate full floor box depth result in the cover projecting above floor level — creating a trip hazard and allowing moisture ingress that damages the hydraulic mechanism.
  • Retrofit projects without assessing existing floor structure
    Timber raised floors or hollow floor systems cannot provide the structural support required. Forced installation leads to pivot axis displacement and door misalignment.
  • Under-specifying for high-frequency commercial environments
    A standard-grade model in a mall entrance or hotel lobby accelerates hydraulic wear and shortens service life — increasing maintenance frequency and replacement costs.

9. Related Products and Application References

10. Frequently Asked Questions

Q1: Which floor spring is suitable for heavy glass doors?

For full-glass doors 12 mm thick and above, the S275 or S280 is recommended based on verified door weight and width. Large glass panels in hotel lobbies, mall entrances, and corporate offices typically exceed 100 kg — the S280 is the primary specification for these applications. Where floor box depth is limited, the narrow-type S275 offers strong load performance in a more compact installation.

Q2: How do I choose the right floor spring for my project?

Confirm door panel weight and width, assess floor installation conditions, then submit this data to a qualified supplier for torque verification and model confirmation. Do not select based on door weight alone — door width and usage frequency are equally important to a correct specification.

Q3: What is the difference between a floor spring and a transom closer?

A floor spring is embedded in the floor, bears the full structural weight of the door panel, and provides high load capacity — the standard specification for glass doors, heavy doors, and commercial entrances. A transom closer mounts above the door frame with moderate load capacity, and is better suited for aluminium and wooden doors where floor installation is not feasible. The key differences are installation position, load capacity, and compatible door types.

Q4: Which floor spring is recommended for commercial entrances?

Hotel lobbies, department store entrances, and office building main entrances require a door hardware system rated for high-frequency use with stable hydraulic performance over extended periods. The S280 is the standard recommendation — providing the load capacity, durability, and consistent closing control that demanding commercial entrance environments require.

Need Help Specifying the Right Floor Spring?

Provide your door type, door weight, door width, and installation conditions — CHIEN CHIN's technical team will assess your project and recommend the most suitable door hardware configuration.

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