Reliable Reinforcement Support for Correct Concrete Cover

Getting reinforcing mesh off the ground is easy; holding it at the position specified for the concrete element is what matters. Rally Bar Chairs support reinforcing mesh & reo bar at controlled heights before & during concrete placement, helping concreters, builders & construction crews establish consistent reinforcement positioning across slabs on ground, driveways, footings & other reinforced concrete work.

Also known as reo bar chairs, reinforcement chairs, mesh chairs, plastic bar chairs or concrete bar chairs, Rally Bar Chairs are available in multiple support heights for different reinforcement requirements.

For accurate site set-out before the steel is positioned, Measuring & Layout Tools provides useful equipment for checking dimensions, levels & layout.

Chair height should come from the reinforcement requirements, not from whichever bag happens to be open on site.

What Are Rally Bar Chairs?

Bar chairs create controlled support beneath reinforcement so the steel can be positioned within the concrete according to the project requirements.

Rally plastic bar chairs are used beneath reinforcing mesh or reo bar during concrete preparation. They provide support points that help prevent reinforcement from simply resting on the substrate beneath the slab.

You may also see these products identified as:

► Bar chairs
► Reo bar chairs
► Reinforcement chairs
► Plastic bar chairs
► Reo chairs
► Mesh chairs
► Reinforcing mesh supports
► Concrete bar chairs
► Slab-on-ground bar chairs
► Reinforcement spacers
► Combination bar chairs

Combination bar chairs provide two support positions from one product. Rally documentation includes configurations such as 25/40mm, 50/65mm & 75/90mm, while taller options including 125/130mm & 145/150mm are represented across the broader range.

Versions with clips & without clips are also available across relevant Rally products.

Why Choose Rally Bar Chairs?

Once concrete placement starts, reinforcement that's already sitting too low becomes far harder to correct properly.

Correctly selected bar chairs establish support points before the pour, giving crews an opportunity to inspect reinforcement height, identify unsupported areas & correct displaced components while the steel remains accessible.

Practical advantages include:

► Supporting reinforcing mesh & reo bar
► Helping establish the specified reinforcement position
► Supporting concrete-cover requirements
► Reducing unsupported areas beneath mesh
► Providing repeatable support heights
► Offering dual-height combination options
► Providing clip & non-clip configurations across relevant products
► Supporting more organised pre-pour inspection

Rally documentation states that its bar chairs comply with AS 2425. Project-specific engineering, reinforcement, durability & compliance requirements should still be confirmed against the applicable drawings, specifications & product documentation.

Common Applications

A house slab, driveway & commercial concrete element can all use reinforcement chairs without needing the same chair configuration.

Rally Bar Chairs can support reinforcement across compatible applications including:

► Slabs on ground
► Concrete slabs
► Reinforcing mesh installations
► Reo bar installations
► Driveways
► Footings where specified
► Pavement work
► Residential construction
► Commercial construction
► General concreting projects

Slab-on-ground work is a particularly familiar application. Bar chairs hold reinforcing mesh above the prepared base so the reinforcement can be positioned according to the slab design before concrete is placed.

Large mesh sheets create another practical challenge: support needs to extend across the reinforcement rather than exist only around its perimeter. Low areas, unsupported laps or displaced chairs can alter the position of the steel even when most of the setup looks correct.

Edges & penetrations deserve their own inspection. Service penetrations, mesh laps, access paths & work by other trades can disturb reinforcement after the original chair layout has been completed.

For broader preparation before demanding site work, Spring Jobsite Prep Getting Your Gear Ready provides additional jobsite guidance.

Product Selection Guide

Start with the required reinforcement position, then select the chair that supports it.

Match The Chair Height To The Job

The numbers on a combination chair describe available support positions—not different strength ratings.

Rally bar-chair configurations documented across the range include:

Not every concrete job needs the same chair height. Select from the actual reinforcement details rather than assuming a 50mm, 65mm or 75mm chair is standard for every slab.

Product availability, pack configuration & clip style can vary across the Rally range, so check the exact product option when ordering.

Understand Combination Bar Chairs

Two heights from one chair can be useful when the correct orientation is understood before installation.

A 25/40mm combination chair can provide either a 25mm or 40mm support position. The same principle applies to 50/65mm & 75/90mm configurations.

That flexibility can make combination chairs practical across concrete work requiring different reinforcement levels.

Don't treat the two numbers as a tolerance range. They represent distinct support positions created by the chair's configuration.

Decide Whether Clips Are Required

Supporting the reinforcement & retaining it at the chair are related but separate considerations.

Rally documents relevant bar chairs with clips & without clips.

A clip configuration can help retain compatible reinforcement at the support point, while a non-clip chair provides straightforward support where that arrangement suits the reinforcement setup.

Check the individual product rather than assuming every Rally chair uses the same retention method.

Check The Complete Reinforcement Setup

A chair can be perfectly positioned while the mesh beside it is still sagging.

Before concrete placement, inspect for:

► Unsupported mesh
► Low reinforcement
► Displaced chairs
► Incorrect chair heights
► Sagging between supports
► Disturbed laps
► Movement around penetrations
► Damage beneath the reinforcement
► Changes caused by site traffic

Look across the entire reinforcement plane. Correct chair selection is only useful when the overall arrangement keeps the steel where the project requires it.

Choosing Between Rally Bar Chair Heights

The quickest way to make a poor selection is to assume taller means better.

The project documentation should decide which row matters. Chair height isn't something to increase for additional reassurance.

Where the required height isn't clear, confirm the reinforcement details before ordering rather than making the decision from slab depth alone.

Bar Chairs & Concrete Cover

Chair height & concrete cover are connected, but they aren't automatically the same measurement.

Concrete cover describes the distance between the reinforcement & the relevant concrete surface. A bar chair helps establish reinforcement position, while the resulting cover can also depend on the dimensions & arrangement of the reinforcement itself.

Consider:

► Chair height
► Reinforcement diameter
► Mesh wire dimensions
► Reinforcement arrangement
► Supporting surface
► Mesh laps
► Mesh deflection
► Edge conditions
► Movement during construction

This is why choosing a 40mm chair doesn't automatically prove that every part of the finished reinforcement has 40mm of cover. Read the reinforcement details as a complete arrangement.

How Many Bar Chairs Does A Slab Need?

There isn't one chair quantity or spacing that should be copied across every slab.

The support arrangement can vary according to:

► Mesh type
► Reinforcement stiffness
► Chair configuration
► Required reinforcement level
► Mesh laps
► Project design
► Localised loads during preparation
► Applicable construction requirements

The practical objective is consistent reinforcement support without unacceptable sagging or displacement. Follow the engineering drawings, project specification & applicable requirements rather than relying on a generic spacing figure from another project.

If the mesh moves noticeably between supports, investigate the setup before the concrete arrives.

Before The Pour

The last useful inspection happens while every chair can still be reached.

Walk the prepared area & ask:

► Are the specified chair heights installed?
► Is the reinforcement sitting consistently?
► Have workers displaced any supports?
► Are laps properly supported?
► Have penetrations disturbed nearby mesh?
► Are edges still positioned correctly?
► Has work beneath or around the steel altered the setup?
► Does the reinforcement match the project details?

A pre-pour inspection should look for patterns rather than isolated problems. One low section can indicate missing supports, incorrect chair orientation or disturbance elsewhere in the reinforcement.

For more on working effectively when site conditions leave little room for preparation mistakes, read The Jobsite Doesn't Forgive. We Do..

Expert Tips

Separate chair heights before work begins. Keeping 25/40mm, 50/65mm, 75/90mm & taller options clearly identified reduces accidental mixing during reinforcement setup.

Read both numbers on combination chairs. Orientation determines which support height is being used.

Watch access paths through the reinforcement. Repeated foot traffic can disturb previously checked chairs & mesh.

Give laps their own check. Overlapping reinforcement changes the local arrangement & may require support according to the project details.

Inspect after service trades finish. Plumbing, electrical or other work around penetrations can alter reinforcement that was correctly positioned earlier.

Protect specified layers beneath the reinforcement. Chair installation & movement across the work area should avoid unnecessary damage to membranes or prepared surfaces.

Recheck the setup after any significant disturbance. Moving mesh to gain access can shift several supports beyond the area being worked on.

Don't make lifting mesh during concrete placement the positioning method. Establishing reinforcement support beforehand allows the arrangement to be inspected while corrections remain practical.

For another trade-focused perspective on dependable equipment & preparation, read A tool is not just a tool. It’s a promise..