Time and material works in demolition are a proven organizational and billing model for deconstruction projects with hard-to-quantify boundary conditions. They are used when components are concealed, as-built plans are incomplete, or special protected interests (e.g., residents, historic fabric, sensitive installations) must be considered. In such situations, working on an effort basis allows precise control of personnel, equipment, and methods—such as the use of concrete pulverizers or hydraulic rock and concrete splitters—and supports a controlled, low-vibration approach in concrete demolition, building gutting, or special demolition.
Definition: What is meant by time and material works in demolition
Time and material works in demolition are services that are billed not on a lump-sum or unit-price basis, but based on actual effort. The basis is documented hours, equipment and consumables used, as well as verifiable records of performance. This form is suitable for selective deconstruction, unclear quantities, variable structural states, and tasks with high uncertainty—such as unexpectedly dense reinforcement, restricted access, or stringent requirements regarding noise and vibrations. Time and material works create flexibility, increase transparency in the construction process, and enable situational selection of appropriate procedures such as hydraulic splitting, cutting, or crushing.
Use cases: When time and material works in demolition make sense
Time and material works are especially effective where the scope of work can only be defined concretely during execution. This includes interior demolition with limited load-bearing capacity, deconstruction in existing structures with live utilities, damage events, or partial deconstruction on complex structures. In these scenarios, devices such as concrete pulverizers or hydraulic splitters can be deployed as needed to progressively release components, expose reinforcement, and direct material flow in an orderly way. The close interlinking of site management, documentation, and equipment selection keeps control over quality, pace, and risks.
Scope of services and distinctions
The scope under time and material includes targeted dismantling, rebar cutting, splitting or crushing of concrete/rock, piecemeal removal, and safe transport to the drop or collection point. Preparatory ancillary works (e.g., protective enclosure, protective wall) are to be distinguished and should be agreed separately. A clear structuring into labor, equipment, and material items is common, supplemented by setup, waiting, and documentation times. For billing, daily timesheets and quantity takeoffs with photo documentation are helpful to keep progress transparent.
Technology selection under time and material: controlled deconstruction
The strength of the approach lies in its methodological flexibility: depending on the structural state, procedures are combined to minimize vibrations, noise, and dust and to preserve structural stability. Frequently used equipment groups are:
- Concrete pulverizers: For precise biting, crushing, and separating of concrete components; well suited to exposing and separating reinforcement, especially in selective deconstruction and in concrete demolition within confined areas.
- Hydraulic splitters: Hydraulic, low-vibration splitting of concrete and natural stone; advantageous for massive cross-sections, sensitive environments, or in structurally critical phases.
- Hydraulic power packs: Power supply for mobile and hand-guided attachments; a central component to ensure consistent drive power in the rhythm of the respective crew.
- Hydraulic shear and multi cutters: For universal cutting and crushing tasks in mixed demolition when material changes or varying component thicknesses occur.
- Steel shear: For efficient cutting of reinforcement, beams, and metallic installations during dismantling.
- Rock wedge splitter: Specifically for pinpoint splitting tasks in rock or heavily reinforced concrete; can also be used in borehole grids.
- Concrete pulverizers in combination with tank cutters: In industrial deconstruction and building gutting, when vessels, shafts, or hollow bodies must be opened in a controlled manner and subsequent concrete remnants removed.
Areas of application and typical procedures
Concrete demolition and special demolition
In demanding deconstruction projects, time and material operation allows an adaptive combination of concrete pulverizers for selective size reduction and hydraulic splitters for low-vibration release of massive sections. This enables stepwise removal of components and controlled alteration of load paths.
Building gutting and cutting
In building gutting, non-load-bearing elements and installations are separated. Multi cutters, hydraulic shear, and steel shear perform material-appropriate dismantling, while concrete pulverizers remove remaining concrete lamellae or dowel areas. Hydraulic power packs ensure the power supply and takt (supported by mobile hydraulic power units).
Rock excavation and tunnel construction
Hydraulic splitters and rock wedge splitters are used to release rock in a controlled way—for example in cross-section enlargements, niches, or portal zones. Working on a time and material basis facilitates reacting to varying rock structures and unforeseeable joints.
Natural stone extraction
During selective release of natural stone, hydraulic splitting methods reduce blasting requirements, noise, and vibrations. Time and material works allow a takt adapted to block cutting and minimize material losses.
Special applications
In sensitive environments—hospitals, laboratories, industrial facilities—low-vibration methods help. Concrete pulverizers for controlled edge demolition and splitters for stress relief of components lower risks for adjacent usage units.
Work preparation and interfaces
Clear work preparation is the key to efficient time and material works. Essential are site surveys, access and load-bearing capacity concepts, utility isolation, and a coordinated takt plan for equipment, crew, and disposal. Short communication paths between site management and crew leadership enable flexible switching between shearing, splitting, and cutting procedures.
Investigation and component assessment
Openings, probes, and rebar detection reduce uncertainties. This makes it possible to decide in good time whether concrete pulverizers will grip sufficiently or whether splitters need to be set.
Access, logistics, load-bearing capacity
Internal transport, slab load-bearing capacity, and load transfer determine equipment sizing and step sequence. Hydraulic power packs can be positioned decentrally to keep hydraulic hose line lengths short and to minimize pressure losses.
Documentation and billing in time and material operation
Time and material works require clean documentation to ensure transparency for all parties. Daily countersigned T&M reports, quantity takeoffs with location reference, and photo documentation of sub-steps have proven effective.
Typical cost elements
- Labor hours by qualification and role
- Equipment usage (e.g., concrete pulverizers, hydraulic splitters, hydraulic power packs)
- Consumables and operating supplies, wear parts
- Setup, relocation, and waiting times
- Transport, disposal, and interim storage
Quantity takeoff and proof of performance
Component-based quantity takeoffs (segment, thickness, reinforcement ratio) facilitate later evaluation. Overviews of pulverizer bites, splitting cycles, and cut lengths support comparability between sections.
Safety, health, environment
The choice of low-vibration methods (splitting, shears) helps limit vibrations and noise. Dust is reduced by wetting, dust extraction, and clean cutting. Personal protective equipment, safe routing of hydraulic hose lines, and pressure relief on hydraulic systems are mandatory. Legal requirements and recognized rules of the art must be observed; binding case-by-case assessments remain the responsibility of the competent specialist bodies.
Productivity control under time and material
Even without rigid unit prices, performance and quality can be controlled. Clear takts, defined daily goals, and rapid equipment changeovers between shearing, splitting, and cutting are important. Metrics such as component thickness per hour, split meters per shift, or pulverizer bites per segment make progress visible.
Setup optimization
Interchangeable jaws on shears and pulverizers, tool-proximate power packs, and matched hose lengths shorten downtime. The crew setup should be designed for the dominant activity (e.g., pulverizer work) while serving splitting or cutting tasks in parallel.
Material flow, sorting, and recycling
Selective separation begins at the component: concrete pulverizers release concrete and expose steel; steel shear cut reinforcement into clean fractions. Splitters create defined fragments that can be moved safely and loaded in a targeted manner. Clean fractions improve recycling and reduce disposal costs.
Typical risks and countermeasures
- Unexpected reinforcement: Pre-investigation, keep pulverizers/shears ready, adapt splitting pattern.
- Confined access: Handheld tools/manual demolition shear, compact hydraulic power packs, staged logistics.
- Sensitive neighborhood: Prioritize splitting, plan work windows and shielding.
- Unclear scope limits: Specify scope descriptions, reconcile T&M reports daily.
- Moisture/dust: Wetting, dust extraction, suitable PPE, non-slip work surfaces.
Step-by-step approach in T&M operation
- Component survey and exploration (probes, detections, access)
- Procedure selection: define shearing, splitting, and cutting strategy
- Equipment and crew planning with hydraulic power pack supply
- Protecting the surroundings (protective enclosure, protective wall, and utility management)
- Test area and takt definition, fine-tuning of the method
- Serial execution with ongoing documentation
- Interim acceptances, adjustments for changed boundary conditions
- Clean separation by material type, removal, cleaning of areas
Practice focus: selection criteria for concrete pulverizers and splitters
Decisive factors are component thickness, reinforcement density, accessibility, and permissible vibrations. Thin-walled components with moderate reinforcement can be processed efficiently with concrete pulverizers. For massive cross-sections or strict vibration limits, hydraulic splitting is recommended. Combinations are common: split first to reduce stress, then use pulverizers to remove segments and expose reinforcement.
Documentation and evidence preservation
Clear, concise reports with location plans, photos, and time records facilitate billing and quality assurance. Markings on the component, numbered sections, and labeling of the splitting or pulverizer sequence create traceability and support later evaluations for method optimization.