Utility lines are the invisible lifeline of buildings, facilities, and infrastructure. They transport electrical energy, drinking water, gas, heat, and data and connect service connections to higher-level networks. In construction, deconstruction, and industrial environments, proper handling of these lines determines safety, schedule adherence, and quality. When working on concrete structures, foundations, or in rock, adapted working methods and tools are important to locate, protect, expose, or remove lines in a controlled manner. A special role is played by gentle methods such as the targeted use of concrete pulverizers and stone and concrete splitters, which minimize vibrations and protect adjacent line sections from damage.
Definition: What is meant by a utility line
A utility line is a pipe or cable that supplies consumers with media or energy. This includes, in particular, power cables, drinking water pipes, gas pipes, district heating pipes, as well as telecommunications and fiber-optic cables. Utility lines run underground, within wall and slab layers, in shafts and cable corridors, or visibly in plant rooms. They form part of a tiered network from main supply to the service connection and on to the internal distribution network in buildings and facilities. They differ from drainage and exhaust air lines, which carry media away. Planning, construction, operation, and deconstruction of utility lines follow recognized engineering standards, taking into account clearance distances, cover depth, identification, and documentation.
Structure and types of utility lines
Utility lines are designed differently depending on the medium, pressure rating, and environment. They consist of the load-bearing pipe or cable, mechanical and thermal protective layers, sealing systems at transitions and penetrations, as well as built-in components such as shut-off and safety devices.
- Electrical energy: underground low- and medium-voltage cables with copper or aluminum conductors, insulation and sheath layers, often routed in protective conduits.
- Drinking water: pipes made of ductile iron, steel, stainless steel, PE, or composite systems; service connections with shut-off and metering devices.
- Gas: steel or PE lines with increased requirements for tightness and identification; cathodic corrosion protection for steel.
- District heating: pre-insulated jacket pipes (supply and return) with leak monitoring, ball joints, and expansion pieces.
- Telecommunications/fiber optics: micro-ducts and multi-duct protective conduits, cable ducts, jointing and splice points.
Materials and protection systems
Metallic lines (steel, cast iron, copper) offer high strength but require corrosion protection. Thermoplastic lines (PE, PVC-U) are corrosion-resistant and flexible but require adapted installation and welding techniques. Cable systems have multilayer insulation and mechanical jackets. Protective conduits, sand bedding, warning tapes, and route marking improve operational safety. Penetrations through concrete components are constructed with wall sleeves and sealing systems to ensure water tightness and fire protection.
Planning, routing, and clearance distances
The routing of utility lines is guided by network structure, terrain profile, structural joints, and connection needs. Important criteria include media compatibility, crossing rules, minimum cover depths, clearance distances, and accessibility for maintenance. In existing buildings, routes run in shafts, installation zones, and ceiling voids; in civil works, lines usually run in a corridor band with a clear sequence.
- Clearance distances: medium-specific minimum distances between lines and to foundations, columns, piles, and reinforcement.
- Routing level: defined elevation levels to keep crossings and parallel runs low-conflict.
- Crossings: at right angles and with protective conduits where mechanical loads are expected.
- Accessibility: installations such as gate valves, control cabinets, and joints must be reachable and documented.
- Identification: warning tapes, marker stones, manhole covers, and as-built plans ensure retrievability.
Location, line information, and exposure in existing structures
Before demolition, earthworks, or core drilling, the position of existing utility lines must be clarified. The basis is utility operator information, as-built plans, and construction-accompanying location surveys. Where the position is unclear or distances to the intervention area are small, trial trenches and hand excavations are required. Only when lines are clearly located and secured may removal or breakthroughs begin.
- Obtain line information and review plans; mark discrepancies.
- Site walk-down and record surface indicators (markings, manholes, service connections).
- Carry out location using suitable methods (e.g., cable- and pipe-specific measuring procedures, passive and active location).
- Create trial trenches or core drillings for verification; exposure by hand only.
- Implement protective measures: supports, temporary bearings, protective conduits, barriers.
- Perform utility power isolation, depressurize, or clarify operating conditions with the operator if work on the line itself is planned.
When exposing lines in a concrete environment, controlled concrete removal is recommended to avoid damaging jackets, insulation, and sealing systems. Concrete pulverizers allow near-edge removal of concrete with good control. Stone and concrete splitters separate massive concrete zones with low stress, for example at foundation underpins or blockages over line penetrations.
Construction and deconstruction methods around utility lines
The choice of method depends on the medium, line construction, location, and ground conditions, as well as the adjacent structure. The goal is to minimize vibrations, impact energy, thermal effects, and spark generation to maintain operational safety and tightness.
Gentle concrete removal at line penetrations
For line penetrations in walls, slabs, and foundations, a sequential approach is sensible: pre-drilling or scribing, locally confined nibbling with concrete pulverizers, then subsequent segment-by-segment release. In areas with high reinforcement density, stone splitting cylinders or stone and concrete splitters can be used to deliberately initiate compression cracks and release the concrete cover in a controlled way. This reduces vibration and protects cable jackets, pipe coatings, and joints.
Controlled dismantling of steel and cast-iron lines
For removing decommissioned steel or cast-iron lines, cutting and shearing methods with low spark generation are suitable. Steel shears and multi cutters enable sectional dismantling, even in tight installation situations. Seals, flanges, and fittings are loosened separately to avoid unintended damage to coatings.
Hydraulic power supply and tool combinations
For compact, mobile workplaces—such as in shafts, tunnels, or confined plant zones—portable hydraulic power units provide the energy supply for concrete pulverizers, splitters, combination shears, and other hydraulic tools. A harmonized system facilitates changing the attachments, reduces setup times, and increases process reliability.
Application areas with a special relation to utility lines
Utility lines are present in many fields of work. The following application areas present typical requirements for planning, protection, and deconstruction.
Concrete demolition and specialized deconstruction
In selective deconstruction of foundations, retaining walls, and slabs, line penetrations, cable corridors, and service connections are often within the intervention area. In line with concrete demolition and deconstruction practice, concrete pulverizers enable tactile work along the line routing, while stone and concrete splitters release massive components without impact energy.
Strip-out and cutting
During strip-out, utility lines must be identified, isolated, and secured before cutting. After removing cladding, careful dismantling follows. Multi cutters and combination shears support cutting work on metallic line sections and cable trays; concrete breakthroughs are prepared in a controlled manner.
Rock excavation and tunnel construction
In excavations, headings, and tunnels, temporary utility lines for energy, water, and communication are routed. Gentle removal methods, such as splitting rock or concrete with hydraulic systems, limit vibrations and protect temporary media lines and instrument cables.
Natural stone extraction
Quarries also use media supplies for operations, dewatering, and safety systems. Lines are secured during block release and when opening up new extraction faces to avoid downtime and damage.
Special operations
In emergencies, line breaks, or acute hazards, controlled, low-vibration access to the damage point is crucial. Tools with high metering capability and hydraulic drive support precise opening of slabs, shafts, and covers directly in the vicinity of lines.
Penetrations, tightness, and fire protection at lines
Penetrations in water- or gas-tight components require coordinated wall sleeves, sealing systems, and, where applicable, firestopping measures. During deconstruction, these zones are particularly sensitive. Segment-by-segment exposure, removal of surrounding concrete with concrete pulverizers, and controlled releasing of sealing elements prevent consequential damage. For new work, the medium, pressure, movements (settlement, thermal expansion), and the component class must be considered.
Quality assurance, documentation, and digital as-built data
Reliable documentation secures operation and future interventions. As-built surveys, georeferenced route plans, photo documentation of exposure, and updating of service connections are part of this. Digital models of the structure and the line network support clash detection, construction phase planning, and later maintenance. On-site changes must be promptly incorporated into the as-built data.
Safety, permits, and responsibilities
Work on or near utility lines requires coordinated permits and protective measures. These include isolation or depressurization, defining protection and hazard zones, selecting low-spark procedures, and providing suitable shut-off and leakage control means. Legal requirements and local specifications must be observed. The information in this article is of a general nature and does not replace coordination with the responsible operators and supervisory authorities.
Material damage, causes, and rehabilitation strategies
Typical damage patterns arise from aging, corrosion, settlement, overloading, external impacts, or thermal stress. Material- and medium-appropriate rehabilitation preserves tightness and structural integrity.
- Metal pipes: corrosion, pitting, cracking at welds; rehabilitation by partial replacement, coating, repair clamps.
- Plastic pipes: stress cracks, necking, weld seam defects; rehabilitation by coupling or segment replacement.
- Cables: sheath damage, moisture ingress, joint defects; rehabilitation by drying, joint replacement, new installation.
- District heating: insulation moisture, jacket failure; rehabilitation by section replacement and tightness monitoring.
Sustainability and resource protection
Resource-friendly work around utility lines includes minimizing vibrations, dust, and noise, avoiding media leakage, and separating removed components by type. The controlled use of stone and concrete splitters and concrete pulverizers reduces secondary damage and waste volumes. Metallic line sections and fittings can often be returned to the material cycle.
Avoiding typical mistakes
- Starting work without complete line information and location survey.
- Using impact and vibration methods directly on line jackets.
- Creating or removing penetrations without protective conduit or fire protection details.
- Insufficient securing of exposed lines against movement, kinking, or loads.
- Documentation gaps for route changes and service connections.
Terminology and placement in the construction workflow
Utility lines differ from disposal lines and process lines in function and operating mode. In the construction workflow, they must be considered at an early stage: from the as-built analysis to construction phase logistics through to commissioning. Especially for interventions in concrete and reinforced concrete components, controlled removal plays a key role. Here, concrete pulverizers have proven themselves for near-edge work and stone and concrete splitters for massive components, complemented by hydraulic drives and shearing tools for metallic line segments.