Wire mesh is an integral component in many concrete construction projects across the UK. When placed correctly within concrete elements, wire mesh reinforces the structure and enhances its load-bearing capacities and durability. Understanding optimal wire mesh placement is therefore critical for engineers, contractors and developers seeking to build robust concrete structures. Consulting with professionals experienced in fencing Aldershot can provide valuable insights into the proper placement of wire mesh to ensure the structural integrity and longevity of concrete constructions.
Properly placing wire mesh may seem straightforward but failing to do so correctly can severely undermine the structural integrity of concrete.
Types of Wire Mesh for Concrete
There are three predominant types of wire mesh integrated into concrete structures in the UK:
Welded Wire Fabric
- Consists of spaced transverse and longitudinal wires welded at intersections
- Available in different spacing, wire gage and corrosion protection levels
- Provides uniform stress distribution and strength in two directions
- Offers ease of handling and placement compared to expanded metal
Expanded Metal Mesh
- Created by slitting and stretching metal sheets to form diamond-shaped openings
- Various standard sizes and metal thickness available
- Provides versatility for applications needing drainage/ventilation
- More rigid than other wire mesh types
Galvanized Wire Mesh
- Fabricated from steel wire coated with zinc for corrosion protection
- Better resistance to weather exposure than standard carbon steel mesh
- Requires extra care during placement to avoid damaging protective coating
Each wire mesh type has particular advantages suiting them for certain applications. Galvanized mesh, for instance, is well-suited for structures needing weather protection. When determining the appropriate wire mesh, consider factors like concrete use, loading conditions and environmental exposure.
Placing Wire Mesh in Concrete
Placing wire mesh properly is vital for it to fulfill its reinforcement role. Follow these key guidelines when positioning mesh:
Depth
- Place wire mesh around the midpoint of a concrete component’s thickness
- Slabs up to 200mm thick – position mesh 50mm from the bottom face
- For thicker slabs, maintain 50-75mm cover on both outer faces
- Consistent depth aids proper stress transfer between concrete and wire mesh
Spacing and Positioning
- Use concrete spacer blocks or chairs to hold mesh in place
- Prevent wire mesh layers from touching – maintain at least 50mm gap
- Overlapping adjacent sheets by one grid spacing ties layers together
- Position mesh evenly across component’s length and width
Tying and Securing
- Tie junctions of adjacent mesh sheets with binding wire
- For large sheets, add ties at 300-450mm intervals along sheet
- Secure mesh properly to all spacer blocks/chairs
- Prevent mesh displacement when pouring concrete with multiple tie-downs
Taking measures to install mesh correctly will deliver optimal concrete reinforcement.
Best Practices for Wire Mesh Placement
Slabs and Foundations
- Place sheets longitudinally in foundation walls, transversely in slabs
- Use higher strength WWF grades in ground slabs than suspended floors
- Offset slab mesh layers to stagger joints & enhance load distribution
- In foundations, ensure mesh continuity at wall bases and corners
- Avoid mesh overcrowding in thick slabs – impact consolidation
Walls and Vertical Elements
- Place mesh around centerline of walls up to 300mm thick
- Include multiple mesh layers in wider walls to provide sufficient cover
- Use vertical and horizontal cross-ties where mesh sheets adjoin openings
- Stagger mesh layers vertically at wall intersections and tile crossovers
UK Climate Considerations
- Alter mesh placement depth for protection in extreme weather exposure
- Use spacer blocks/chairs with integral ties to minimize mesh movement
- Store mesh sheets off the ground under protective coverings
- Remove standing moisture on mesh before enclosing in concrete
Following application-specific best practices for wire mesh placement produces robust reinforced concrete constructions.
Frequently Asked Questions
What is the role of wire mesh in concrete construction?
- Reinforces concrete against tensile cracking and loading stresses
- Enhances structural strength and impact resistance
- Provides continuity of reinforcement
Is wire mesh always necessary in concrete projects?
- Building codes mandate wire mesh for structural stability in most applications
- Exceptions when using fiber reinforcement or steel rebar only
- Recommended to provide secondary backup reinforcement at minimum
Can wire mesh be added to existing concrete structures?
- Difficult to retroactively position mesh properly within concrete
- Better to use external reinforcement like fiber-reinforced polymer wraps
- Consult a structural engineer before attempting
How does wire mesh placement differ in residential and commercial construction?
- Commercial structures often have thicker concrete elements requiring more mesh layers
- Lighter mesh gages and grades commonly used in residential construction
- Cover requirements may also differ slightly
What are the consequences of improper wire mesh placement in concrete?
- Compromised strength against stresses, cracking, weather effects
- Distortion, unraveling or rupture of poorly-secured mesh when pouring concrete
- Premature deterioration and reduced service life
Are there any alternative reinforcement methods to wire mesh in concrete?
- Steel rebar is sometimes used instead for major structural components
- Synthetic macro fibers added directly into concrete mix
- Steel fibers or reinforced polymer wraps also used
Proper wire mesh selection and placement is key for reinforced concrete integrity across residential, commercial and infrastructure projects. This guide covers core considerations for all UK applications. Please reach out for any additional queries on utilizing wire mesh in concrete construction.
Thanks for reading our post, feel free to check out our other services:
