DORMA BTS 75V Floor Spring EN 1-4 Hold-Open 105° for Fire and Smoke Doors

Product Overview

DORMA BTS 75V floor spring is used for single and double leaf doors in commercial and public buildings, featuring adjustable closing force in the EN 1-4 range. Suitable for doors up to 1100 mm wide and 120 kg weight, it is approved for installation in fire-rated and smoke-control doors, offering compliance for safety-critical fitouts.

Its integrated hold-open mechanism at 105° distinguishes this model from generic floor springs, providing controlled door retention for operational convenience without compromising fire safety requirements. This feature reduces the risk of accidental door closure during high-traffic periods and is particularly beneficial for procurement in hotels, office lobbies, and healthcare facilities where temporary hold-open and certified fire safety must coexist.

Key Features

• Adjustable closing force EN 1-4 ? covers door widths up to 1100 mm and weights up to 120 kg


• Integrated hold-open function ? holds door securely at 105° for controlled access usage


• Regulated closing speed ? two independent valves allow precise adjustment from 175° to 0°


• Opening damping mechanism ? protects walls by slowing door between 70° and 90°


• Approved for fire and smoke doors ? compliant installation for safety-critical applications


• Universal handing ? suitable for left- and right-opening doors without extra adaptation

Technical Specifications

• Closing Force: EN 1-4 (continuously adjustable)


• Maximum Door Width: 1100 mm


• Maximum Door Weight: 120 kg


• Hold-Open Angle: 105°


• Opening Angle Range: up to 175°


• Damping Mechanism: 70° to 90° opening


• Approved For: Fire-rated and smoke-control doors


• Handing: Universal

Applications

Used in commercial, hospitality, healthcare, and public sector buildings for floor-mounted closure of single or double leaf doors. Suitable for fire-rated and smoke-control doors, high-traffic entrances, and environments requiring temporary hold-open (e.g. office corridors, hotel entries, hospital wards).

Packaging & Shipping

Standard export packaging. Unit includes floor spring body, mounting hardware, and installation manual. Additional accessories such as spindle or cover plate supplied separately as required.