Perforated bricks are widespread in new construction and in existing buildings. They combine low bulk density with good thermal insulation and are used in load-bearing as well as non-load-bearing masonry. For design, execution, repair, and deconstruction, it is crucial to understand how the hole structure influences load-bearing capacity, fastening techniques, and the work method. During conversions or selective demolition, perforated bricks frequently meet reinforced concrete components—depending on constraints, controlled methods using concrete pulverizers or hydraulic rock and concrete splitters may be considered, particularly in the application areas of building gutting, concrete demolition, and special demolition.
Definition: What is meant by perforated bricks
Perforated bricks are ceramic masonry units with predominantly vertical cavities. The perforations reduce weight and thermal conductivity, while the load-bearing webs transfer loads. Perforated bricks are typically laid using thin-bed mortar or lightweight mortar and are available in various formats and compressive strength classes. They serve as exterior and interior wall units for load-bearing walls, partition walls, and veneers; they are not reinforced and are often delivered as precision-ground bricks to enable thin joints.
Structure, properties, and typical formats
The perforation patterns are designed to create air chambers and to align the webs in the directions of load and compression. This results in specific properties: good thermal insulation, moderate sound insulation compared to heavier units, high fire resistance rating, but webs that are more sensitive to concentrated point loads and improper fixings. Typical formats range from handy bricks to large-format precision-ground bricks; the choice influences the number of head joints, installation time, and building physics performance.
Properties and use in masonry design
The combination of perforations, bulk density, and strength class determines where and how perforated bricks are sensibly used. In exterior walls, thermal protection takes priority; in interior walls, structural safety and acoustic requirements do. The perforations lead to anisotropic load-bearing behavior: compressive strength is highest along the perforation axis and lower perpendicular to it. In existing buildings, mixed constructions with reinforced concrete columns, beams, and ring beams are often found.
Thermal protection and energy efficiency
The air trapped in the cavities reduces thermal conductivity. In combination with lightweight mortar and narrow bed joints, exterior walls can, depending on the energy target, function without additional insulation layers. Thermal bridges arise primarily at slab bearings, reveals, and mechanical fixings. Careful detailing, such as thermally optimized bearings and well-planned fixing points, is therefore essential.
Sound insulation and acoustics
Sound insulation strongly depends on surface mass and web geometry. More massive variants achieve better values, while light insulating bricks excel in thermal performance. For installation chases, depth and width must be limited to avoid weakening sound insulation and the structural capacity of the webs.
Load-bearing capacity and fixings
The webs must not be overstressed by point loads. Mechanical anchors require suitable setting methods and access to load-bearing webs; chemical anchors demand thorough borehole cleaning and matched mesh sleeves. Static verifications are often required for medium to heavy loads. For high point loads, load-distributing rails or mounting plates offer advantages.
Manufacturing, mortars, and joints
Perforated bricks are made from clayey raw materials that are formed, dried, and fired. The perforations are produced during extrusion. Thin-bed mortar reduces the mortar content and improves building physics parameters. Head joints in precision-ground bricks can be tight or executed with filler profiles. Lightweight mortar is used for leveling layers and for connections to uneven existing surfaces to mitigate thermal bridges.
Formats and perforation patterns
Large formats reduce the proportion of joints and installation time but require suitable transport and setting aids. In refurbishments, smaller formats are more flexible, especially when adapting to irregular existing geometries. Perforation patterns range from straight to meandering webs; they influence cutting paths, drilling techniques, and the pull-out values of fixings.
Joint quality and connection details
Uniform bed joints contribute significantly to load-bearing capacity. Add-on components such as slabs, lintels, and ring beams must support the thermal and acoustic objectives. At the interface to reinforced concrete elements, restraint and cracking should be avoided by movement joints or defined connection details.
Processing: cutting, drilling, chasing
Working with perforated bricks requires adapted methods to avoid damaging the webs. For cuts, brick saws or cut-off grinders with low-dust extraction are suitable. For drilling, rotary feed without hammer action is advantageous for precise holes into the webs; for chases, keep them shallow, wide, and away from critical zones such as pier cross-sections. Run installations in joint areas wherever possible to preserve load-bearing webs.
Dust and noise protection
Mineral dust generation requires effective extraction, water supply or wet cutting, appropriate filtration, and personal protective equipment. Low-vibration methods contribute to occupational safety and protect adjacent components.
Deconstruction of perforated brick masonry
In selective deconstruction, perforated brick walls are often opened or removed next to reinforced concrete slabs, ring beams, or columns. Because the webs are impact-sensitive, a controlled, low-vibration approach is recommended. For adjacent concrete components, concrete pulverizers have proven effective, as they crush elements, expose reinforcement, and can replace separation cuts. For more massive masonry sections or foundations in mixed masonry, stone and concrete splitters can be considered, especially when vibrations and noise must be minimized. compact hydraulic power units provide the required energy for these tools in the confined work environments of building gutting and special demolition.
Selective demolition in existing buildings
The procedure follows the sequence of load transfer. First, identify bearings, lintels, and ring beams. The wall surface is then released section by section. Where reinforced concrete connections are present, concrete pulverizers enable low-damage exposure before the masonry units are manually removed or reduced in size. For thick wall sections and areas with mastic asphalt or natural stone facing, stone and concrete splitters can accelerate removal without introducing impact energy.
Openings and partial demolition
For door and window openings, temporary shoring of the masonry above is mandatory. After installing a lintel or beam, the panel is opened step by step. In the immediate vicinity of concrete elements, the use of concrete pulverizers reduces shock effects; the perforated brick masonry is then removed course by course. Cutting paths, dust reduction, and clean separation by material type are key objectives.
Handling mixed structural systems
In combinations of perforated brick walls with reinforced concrete columns, beams, or slab edges, different tools are required: concrete pulverizers for reinforced concrete, supplemented by steel shears or multi-cutters for exposed reinforcement and sections, and hand-held tools for the brick masonry. This minimizes damage to retained components and increases the reuse rate of materials.
Safety, environment, and disposal
During deconstruction, attention must be paid to stable intermediate states, dust minimization, and noise protection. When cleanly separated, perforated bricks can be recycled as material or used as recycled aggregate. Mortar residues and contaminants must be removed. Legal requirements for waste categories and documentation of proof must be observed; specific requirements may vary regionally.
Typical mistakes and practical notes
Common weak points include overly deep chases, inadequately cleaned boreholes for chemical anchors, anchors set in thin webs rather than in load-bearing areas, and missing shoring at openings. In refurbishments, identify ring beams, bearings, and joint patterns early, align cutting and demolition methods accordingly, and keep vibrations low. Point loads must be distributed, for example via brackets or mounting plates.
Distinction from other masonry units
Unlike solid bricks or calcium silicate bricks, the focus with perforated bricks is on thermal protection and low weight. This influences fixing techniques, chase strategies, and demolition methods. For high acoustic or compressive demands, heavier unit types may offer advantages; in energy-efficient exterior wall construction, perforated bricks play to their strengths.
Planning interfaces with equipment and site processes
For building gutting, selective demolition, and creating openings, a coordinated equipment selection is advisable: concrete pulverizers for working adjacent concrete components, stone and concrete splitters for massive, brittle elements with low vibration, and hydraulic power packs as the energy source. In natural stone extraction and tunnel construction, the principles of controlled splitting are similar, even though perforated bricks do not occur there. The shared goal remains precise, safe, and low-emission work.
- Planning: site survey, material analysis, load paths
- Execution: low-dust separation cuts, sectional release, source-separated sorting
- Equipment use: concrete pulverizers for concrete, splitters in addition for brittle elements
- Quality: protection of adjacent components, clean edges, controlled vibrations