Description

Dorma Floor Spring BTS80 with Adjustable Hold Open

The Dorma BTS80 is a heavy duty, universal non-handed floor spring designed for single and double action doors. Featuring mechanical backcheck and an adjustable, removable hold-open function, the BTS80 is selected for large, heavy or high-traffic commercial doors where controlled closing and durability are critical.

Key Features

Heavy duty floor spring for high-weight and wide doors.
Mechanical backcheck for door and frame protection.
Adjustable, removable hold-open between 75° and 175°.
Universal non-handed design for single and double action doors.

Specifications

Product Type	Heavy duty double action floor spring
Spring Strength Options	EN3, EN4, EN6
Mechanical Backcheck	Yes
Hold Open	Adjustable 75°–175° (removable)
Maximum Door Weight	300 kg
Overall Dimensions	341 mm x 78 mm x 60 mm
Approximate Weight	7.1 kg

Suitable Uses

Heavy commercial doors.
Wide doors and high-traffic entry points.
Doors exposed to wind or draught conditions.

Available Variants

Item Code	Spring Strength	Maximum Door Width
DOBTS803	EN3	950 mm
DOBTS804	EN4	1100 mm
DOBTS806	EN6	1400 mm

Item Code Family

System	Spring Range	Typical Application
This Product – BTS80	EN3 / EN4 / EN6	Heavy duty and wide commercial doors
BTS75V	EN1–4 Adjustable	Medium commercial doors with backcheck
BTS84	EN2 / EN4	Compact aluminium and glass doors

Download PDF Resources

Dormakaba Access Hardware Brochure

Frequently Asked Questions

DORMA BTS extended spindle options
Extended spindles are used where additional height is required due to thicker floor finishes, raised thresholds, or non-standard installation depths.

Extension Size	Product Code
Standard	45200401
5 mm	DO05SPIN
7.5 mm	DO75SPIN
10 mm	DO10SPIN
12.5 mm	DO125SPIN
15 mm	DO15SPIN
20 mm	DO20SPIN
25 mm	DO25SPIN
28 mm	DO28SPIN
30 mm	DO30SPIN
35 mm	DO35SPIN
40 mm	DO40SPIN
45 mm	DO45SPIN
50 mm	DO50SPIN

Should I use a sealing compound?
Yes. The use of DORMA 2300 Sealing Compound prevents moisture penetration by filling cavities between the floor spring body and the cement box.

This is mandatory in certain applications such as wet rooms (for example, as required under VOB regulations).

Product code: DO2300

What is backcheck?
The integrated mechanical backcheck function protects the wall, frame and door from damage caused by excessively vigorous opening.

What is delayed action?
Delayed action slows the door closing speed for a short period, allowing easier passage for disabled persons, parents with prams, staff with trolleys, hospital beds or similar equipment.

What is hydraulic hold-open?
Hydraulic hold-open allows the door to be held open at any angle between 75° and 175°. The angle at which hold-open begins can be adjusted, typically within the 75° to 105° range.

What is meant by leaf weight?
Leaf weight refers to the total weight of the door leaf, including glass, framing and fittings. The floor spring must be selected to suit the actual door leaf weight, not just door width.