Proper rolling gate demolition is a precise deconstruction operation at the interface between metal and concrete works as part of demolition works. It occurs in industry, logistics, underground garages, factory halls, and loading zones when door systems are replaced, openings enlarged, fire protection requirements adjusted, or buildings are gutted. The focus is on the safe dismantling of the curtain with shaft, drive, and guide rails, as well as on addressing adjacent components such as the lintel, frames, reveals, and foundation interfaces. Especially when adjusting the opening, precise concrete crushers and stone and concrete splitters are key tools from Darda GmbH’s portfolio for precise concrete demolition in existing structures—particularly in special demolition and during gutting.
Definition: What is meant by rolling gate demolition
Rolling gate demolition refers to the systematic dismantling of a rolling gate including all associated components: the curtain (slats, profile, or grille), shaft with torsion spring or tubular motor, bearings and brackets, guide rails, apron and bottom bars, drive unit with control, safety components (e.g., closing edge protection), as well as fixings in masonry or concrete. Demolition also includes adjusting the opening—such as removing or trimming the concrete lintel, reveals, or upstands—when a new door size is required. It thus differs from the mere replacement of individual components and, depending on the objective, touches the application areas of building gutting and cutting as well as concrete demolition and special demolition.
Typical reasons and objectives
Rolling gates are removed when uses change, traffic routes are enlarged, barriers are reduced, energy or fire protection requirements are increased, or damage needs to be rectified. Common objectives include widening or raising the clearance, replacing outdated drives, eliminating collision-related deformations, and preparing for new door types. In refurbishment and conversion projects, rolling gate demolition often takes place in conjunction with other measures of special demolition.
Design principle and components of rolling gates
Rolling gates consist of a curtain formed from slats that winds around a shaft. Guidance is provided in U- or T-shaped rails. Drives are configured as side-mounted motors or tubular motors; for heavy gates, torsion springs provide weight compensation. Fixings engage into reinforced concrete, masonry, or steel frames. Understanding these components is essential to define cut and separation points and to reduce loads in a controlled manner.
Materials and their impact on demolition
Slats are made of steel, aluminum, or stainless steel; insulated variants contain foams or mineral fillers. Guide rails and brackets are made of steel sections. The material selection determines the separation technique: metal cuts with steel shears and Multi Cutters, mineral components with concrete crushers or stone and concrete splitters.
Planning and preparation of deconstruction
A structured preparation minimizes risks, downtime, and damage to the existing structure. Relevant steps:
- Survey of door dimensions, component build-up, fixings, drive technology, and energy supply (power, possibly control).
- Review of connection details at the lintel, reveals, floor connection, and any steel substructures.
- Definition of shoring and safety measures against uncontrolled unwinding of the curtain or spring release.
- Planning of material separation as well as routes for intermediate storage and removal.
- Assessment of the need to enlarge openings or trim concrete components—a typical field of application for concrete crushers and stone and concrete splitters.
Interface coordination
Coordination with electrical, structural, and fire protection disciplines is essential. Particular care is required for fire or smoke closures; textile or spring-balanced systems require specific dismantling steps. Statements on legal requirements are made by the competent authorities; in deconstruction they are taken into account as a precaution.
Work sequence for rolling gate demolition
- Isolate and secure: De-energize electrical connections, lock out and tag out (LOTO). Dismantle safety components.
- Secure the curtain: Fix the curtain against slipping, reduce torsion forces in a controlled manner. For tubular motors, define the door position and release hangers.
- Dismantle periphery: Remove cladding, weather shields, sensors, apron, tension springs. Disconnect and secure the control unit.
- Shaft and bearings: Dismantle bearing pins, brackets, and drive unit. Secure the shaft with a hoist or stand.
- Guide rails: Release fixings or cut profiles step by step. Steel shears and Multi Cutters allow controlled separation cuts on steel sections.
- Remove the curtain: Decouple slats, cut to appropriate lengths, and divide into manageable units.
- Process connection areas: Remove protrusions, anchors, bracket remnants; if the opening is being adjusted, nibble mineral components with concrete crushers or separate them with stone and concrete splitters with minimal cracking.
Tools and methods for metal and concrete separation
Depending on the design, rolling gate demolition requires different tools. Hydraulically driven devices excel with high cutting force and low emissions—an advantage in existing buildings and sensitive environments.
- Steel shears: For guide rails, frames, anchor plates, and brackets. Clean cuts on section steels and sheet metal.
- Multi Cutters: For mixed materials such as slats with fillers; flexible in confined installation situations.
- Combination shears: For switching between cutting and crushing on composite components and reinforcement in edge areas.
- Concrete crushers: For selective nibbling of concrete at the lintel, in the reveals, and at the floor connection; low vibration with precise edge formation.
- Stone and concrete splitters or stone splitting cylinders: For low-crack separation joints and controlled opening of concrete cross-sections when low-vibration work is required.
- Hydraulic power packs: As the energy source for shears, crushers, and splitters; modularly adaptable to the site situation.
- Concrete crushers and steel shears in combination: Combination for gates with welded steel frames embedded in concrete—pre-cut the metal, then selectively remove the concrete.
Cutting torches are only used in rolling gate demolition in special situations, for example with particularly large-format, thick-walled steel sheets beyond typical slat thicknesses.
Enlarging concrete openings and adjustments in existing structures
If the opening is widened or raised after rolling gate demolition, dimensionally accurate, low-vibration methods are required. Concrete crushers allow precise edges that are advantageous for subsequent installation of new door frames. Stone and concrete splitters produce defined separation joints and reduce spalling, protecting the substrate. Such work is part of concrete demolition and special demolition as well as building gutting and cutting.
Cut path and structural consequences
Before removing the lintel or reveals, verify load transfer and any temporary shoring. Cuts are guided to expose reinforcement in a controlled manner and—if required—separate it with steel shears. Pay attention to mineral fillers or insulation during disposal.
Safety aspects and occupational safety
- Spring forces: Relax torsion springs only according to manufacturer principles, avoid uncontrolled movements.
- Fall and crushing hazards: Safeguard against the curtain unwinding, use hoists, define the cutting sequence.
- Electrical safety: Isolate, test, and ground. Disconnect controls with documentation.
- Sparks and fire load: Protect against ignition sources during metal cutting; plan for a fire watch and shielding.
- Noise and dust: Hydraulic separation technology reduces emissions; use point extraction and wetting for mineral work.
Legal obligations vary by region and project; they are generally and proactively considered in deconstruction without replacing a case-by-case assessment.
Material separation, recycling, and disposal
Steel and aluminum from slats, rails, and brackets are collected by type and sent for recycling. Plastics, seals, and mineral fillers are collected separately. Concrete debris from lintel or reveal work can be processed as recycled construction material where permitted locally. Documented separation reduces disposal costs and supports proof obligations.
Special sites and boundary conditions
In underground garages, tunnel portals, and confined halls, working height and ventilation are limited. Compact, hydraulic devices from Darda GmbH enable controlled cutting and splitting with low emissions—an advantage in rock excavation and tunnel construction where roll-up closures at adit entrances or technical enclosures are to be removed. In areas with sensitive production, low-vibration methods and clean cut faces are particularly relevant. For special deployments, for example in explosion-hazard zones, low-ignition working methods and permits are decisive.
Quality assurance and documentation
Dimensional checks of the opening, visual inspection of cut edges, and documentation of service isolations and material flows are integral to a traceable execution. Photos, sketches, and measurement records facilitate a seamless transition to the new build—for example, for mounting new frames or installing alternative closure systems.
Avoiding common mistakes
- Underestimating stored energy in spring systems and the resulting movement of the curtain.
- Unstructured cutting sequence on rails and brackets leading to uncontrolled yielding of components.
- Excessive vibration when breaking out concrete instead of selective work with concrete crushers or stone and concrete splitters.
- Unclear material separation that sacrifices recycling potential and increases costs.