High-Performance Rebar Spacers & Concrete Reinforcement Supports
Rebar spacers and supports maintain specified concrete cover requirements across horizontal slab reinforcement, vertical wall panels, column cages, and heavy foundations. Precise cover positioning prevents steel oxidation, ensures structural load transfer, and satisfies fire-rating criteria mandated by international building codes (including EN 1992-1-1 and ACI 318).
Incorrect concrete cover directly leads to early structural degradation:
Insufficient cover exposes reinforcement steel to moisture, carbonation, and chloride ingress, resulting in spalling, premature corrosion, and section loss.
Excessive cover reduces effective structural depth (d), inducing unintended crack formation on tension faces and decreasing structural shear and flexural capacity.
Selecting the correct spacer variant depends on formwork type, rebar density, mechanical load during concrete placement, and environmental exposure classes (e.g., XC, XS, XD).
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![Clip-On Rebar Spacers]()
Clip-On Rebar SpacersClip-on rebar spacers secure reinforcing steel bars within formwork to maintain exact concrete cover depths during pouring and vibration. Injection-molded from high-density polyethylene (HDPE) or polypropylene (PP), these wheel-style...view more -
![Wheel Rebar Spacers]()
Wheel Rebar SpacersWheel rebar spacers (also known as circular or plastic ring spacers) maintain consistent concrete cover around reinforcing steel bars in vertical and horizontal concrete structures. The circular geometry provides 360-degree stability...view more -
![Heavy-Duty Rebar Chairs]()
Heavy-Duty Rebar ChairsHeavy-duty rebar chairs maintain rebar mat elevation and concrete cover thickness in heavy concrete foundations, precast elements, and bridge decks. Designed to handle extreme dynamic structural loads and heavy foot traffic during pour...view more -
![Rebar Chair Spacers]()
Rebar Chair SpacersRebar chair spacers position reinforcement steel grids and rebar meshes at predetermined clearance heights prior to concrete placement. By maintaining exact concrete cover depth, these spacers ensure total rebar encapsulation,...view more -
![Concrete Rebar Spacers]()
Concrete Rebar SpacersConcrete rebar spacers (also referred to as concrete cover blocks) position steel reinforcement at exact distances from formwork before concrete pouring. Manufactured from fiber-reinforced, high-density cementitious mixtures, these...view more -
![Plastic Rebar Spacers]()
Plastic Rebar SpacersPlastic rebar spacers hold reinforcing steel at the precise distance required from formwork before concrete pouring. Correct positioning maintains specified concrete cover, preventing internal steel exposure, corrosion, and structural...view more
Product Range
Plastic Rebar Spacers
Engineered from high-density polyethylene (HDPE) or polypropylene (PP). Designed for standard cast-in-place slabs, precast elements, and light structural applications where non-corrosive, cost-efficient spacing is required.
Concrete Rebar Spacers
Molded from high-strength fiber-reinforced concrete with compressive strength matching or exceeding structure specifications (≥ 50 MPa). They bond directly with poured concrete, eliminating material boundary seams and maintaining thermal expansion parity.
Rebar Chair Spacers
Multi-cover bar chairs designed with dual or triple cover depths on a single unit. Provide stable base platforms for single and double rebar mats in slab construction and grade beams.
Heavy-Duty Rebar Chairs
High-load structural chairs rated for extreme point loading during rebar cage assembly, heavy mesh placement, and direct foot traffic. Ideal for heavy foundations, civil infrastructure, and thick bridge decks.
Wheel Rebar Spacers
Circular clip-on spacers designed specifically for vertical reinforcement cages. They roll smoothly along internal formwork surfaces during cage lowering, maintaining uniform cover in column forms, shear walls, and bored piles.
Clip-On Rebar Spacers
Fast-fitting mechanical spacers equipped with spring locking clips. They attach securely to rebar diameters from 4 mm to 20 mm without tie wire, preventing shifting during high-frequency concrete vibration.
Key Product Characteristics
|
Feature / Metric |
Plastic Spacers |
Concrete Spacers |
Steel / Wire Chairs |
|
Material Base |
HDPE / PP (Virgin or Recycled Grades) |
Fiber-Reinforced Concrete (≥ 50 MPa) |
Cold-Drawn Steel Wire / Plastic-Capped |
|
Compressive Point Load |
0.5 kN - 2.5 kN |
3.0 kN - 10.0 kN+ |
1.5 kN - 4.0 kN |
|
Thermal Expansion Alignment |
Different from concrete matrix |
Identical to poured concrete matrix |
N/A (Embedded wire) |
|
Fire Resistance Rating |
Class B/C (Melts at high temp) |
Class A1 Non-combustible (≥ 2 hours) |
Class A1 Non-combustible |
|
Formwork Surface Marking |
Minimal (Point contact feet) |
Zero visible footprint |
Risk of rust staining if non-capped |
|
Installation Method |
Snap-fit / Clip-on |
Integrated tie wire or clip |
Position under mat / Tie wire |
Key Specifications
Dimensions & Cover Depths
Standard Cover Depths: 15 mm, 20 mm, 25 mm, 30 mm, 40 mm, 50 mm, 75 mm, 100 mm.
Multi-Cover Units: 20/25/30 mm and 40/50 mm combination profiles.
Compatible Rebar Diameters: Ø 4 mm to Ø 32 mm continuous bar range.
Performance Specifications
Compressive Strength (Concrete Spacers): 50 MPa - 70 MPa at 28 days.
Water Absorption (Concrete Spacers): ≤ 4.5% (Prevents moisture bypass to rebar).
Load Deflection (Plastic Spacers): Max 1 mm deformation under 1.2 kN static point load at 23°C.
Temperature Resistance: Plastic variants rated from -15°C to +60°C without structural brittleness or softening.
Applications
Cast-in-Place Buildings & Slabs
Clip-on plastic chairs and continuous line spacers maintain elevated reinforcement heights over large surface areas prior to pour operations.
Precast Concrete Manufacturing
Concrete spacers match the water/cement ratio and aggregate density of precast mix designs, preventing boundary line shadows on architectural concrete surfaces.
Civil Infrastructure & Marine Structures
High-density concrete spacers meet strict low-permeability requirements for seawater exposed environments (XS exposure classes).
Deep Foundations & Bored Piles
Wheel spacers secured around circular steel reinforcement cages ensure continuous alignment as cages descend into deep excavation shafts.
Selection & Design Considerations
When specifying rebar supports for site installation or precast production, evaluate the following engineering criteria:
Load Requirements during Construction
Calculate maximum concentrated loading, including reinforcement mat weight, concrete discharge pressure, and worker traffic. Use heavy-duty fiber concrete or reinforced steel chairs when loads exceed 2.0 kN per support point.
Environmental Exposure Classes:
Indoor / Low Humidity (XC1): Standard HDPE plastic spacers are acceptable.
Outdoor Corrosion / De-icing Salts / Marine (XS, XD, XF): Fiber-reinforced concrete spacers prevent localized micro-cracking and fluid migration pathways along the spacer-concrete boundary.
Formwork Surface Finish
Architectural concrete requires point-contact plastic feet or concrete spacers made with matching cement types to avoid circular outlines on cured surfaces.
Spacing Density Calculation
Standard structural spacing guidelines require 4 - 6 spacers per square meter for horizontal slabs. Heavy reinforcement cages or large-diameter bars (≥ 25 mm) require reduced spacing intervals (0.5 m - 0.8 m grids) to avoid bar sagging.
Quality & Inspection
Production quality control and testing verification follow standardized protocols:
Compressive Point-Load Testing
Samples undergo crushing tests in accordance with BS 7973-1 to verify failure thresholds under static point loads.
Dimensional Accuracy Checks
Caliper inspection verifies cover tolerances within ± 1.0 mm of nominal depth specifications.
Material Integrity Tests
Plastic polymers are subjected to UV accelerated weathering and cold-impact testing at -10°C.
Fiber concrete spacers undergo freeze-thaw cycle testing and water penetration testing under 5-bar hydrostatic pressure.
Traceability
Production batches are indexed by raw material batch numbers, manufacturing date codes, and compressive strength lab reports.
Supply & Customization Options
Material Formulations
Custom polymer blends available with added UV stabilizers or flame-retardant additives. Concrete mix design ratios can be adjusted using Sulfate-Resistant Portland Cement (SRC) or Ground Granulated Blast-furnace Slag (GGBFS) for aggressive soil conditions.
Private Label & Packaging
Bulk woven bag packaging, carton packing with custom branding, or palletized gaylord boxes tailored for distribution networks.
Custom Concrete Profiles
Tooling and custom mold production available for specialized cover depths (> 100 mm), heavy-load continuous bar channels, or specific radius curvatures.
What Buyers Should Provide
To receive an accurate technical quotation and sample kit, provide the following project details with your inquiry:
Required Cover Depths
Specific millimeter dimensions (15 mm, 25 mm, 50 mm, etc.).
Rebar Diameters
Range of steel reinforcement sizes (Ø mm) being supported.
Material Preference
Plastic (HDPE/PP), Fiber-Reinforced Concrete, or Steel Wire.
Structural Application
Slab, shear wall, column, deep foundation, or precast panel.
Quantity & Delivery Requirements
Volume per item type, packaging constraints, and destination port (FOB / CIF incoterms).
Project Certifications Required
Specify compliance needs (e.g., BS 7973, DIN 1045, ACI compliance).
FAQ
Request a Quote
Submit your project specifications or bill of quantities (BOQ) to our engineering team for technical review and pricing.
Response Time: Technical quotations and sample options dispatched within 24 business hours.
Sample Policy: Sample kits for dimensional and material testing available upon request.
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