Buying Vs renting self-loading concrete mixers

1 Introduction
2 Related articles on Designing Buildings

[edit] Introduction

The decision to buy or rent a self-loading concrete mixer depends on factors including project duration, equipment utilisation, concrete demand, site conditions and the availability of other concrete supply options.

A self-loading concrete mixer is a mobile machine that can combine several functions associated with concrete production. Depending on its design, it can load constituent materials, proportion and mix them, transport fresh concrete around a site and discharge the concrete at the point of use. This can reduce the number of separate items of plant required for some projects.

Renting can reduce the initial capital commitment and may be appropriate for short-term or infrequent requirements. Ownership can become more economical where equipment is used regularly across several projects. The appropriate option should be assessed using whole-life costs and anticipated utilisation rather than purchase or rental price alone.

[edit] When renting may be appropriate

Renting can be suitable for short-duration projects or where concrete production requirements are uncertain. It allows contractors to obtain equipment without committing capital to a machine that may remain idle for long periods.

Rental may be particularly appropriate for small projects, temporary increases in workload or specialist applications where equipment is only required occasionally. It can also provide flexibility where contractors need to select different machine sizes or configurations for different projects.

However, the total cost of renting should include more than the advertised hire rate. Relevant costs may include delivery, collection, insurance, operator costs where applicable, fuel, cleaning charges and additional hire periods caused by programme delays.

Repeated short-term rentals can become more expensive than ownership where a machine is required regularly. Contractors should therefore consider anticipated requirements across their wider programme of work rather than assessing each project in isolation.

[edit] When buying may be appropriate

Purchasing may be appropriate where a contractor has a regular requirement for concrete production and expects the equipment to be used across several projects. Ownership provides direct control over the availability and deployment of the machine and may reduce the need to arrange equipment for each new project.

Self-loading mixers can be particularly useful where construction sites are remote, access to ready-mixed concrete is limited or concrete is required in relatively small or intermittent quantities. They may also be useful on projects where work is spread over a large area and concrete is required at different locations.

However, ownership also creates responsibilities and costs. These include capital expenditure or financing, maintenance, repairs, insurance, storage, operator training, inspections, depreciation and the risk of periods when the machine is not in use.

A purchased machine may retain a residual value at the end of its useful period, although resale value depends on its age, condition, specification, maintenance history and market demand.

[edit] Production capacity and site requirements

Production capacity is an important consideration when selecting a self-loading concrete mixer, but nominal drum capacity should not be confused with actual hourly or daily output.

Actual production depends on a range of factors, including:

usable batch capacity;
loading and mixing times;
material storage and availability;
water supply;
travel distances;
site layout and ground conditions;
operator experience;
cleaning and maintenance requirements;
delays between batches; and
the specification and consistency of the concrete being produced.

Manufacturers may state production capacities based on assumed numbers of batches per hour, but actual output can differ significantly from these estimates. Equipment should therefore be selected using realistic production requirements and allowing for operational delays.

The machine must also be suitable for the physical conditions of the site. Access width, turning space, ground bearing capacity, gradients, terrain and the distance between material storage, mixing and placing locations can all affect productivity and safety.

[edit] Concrete supply and equipment coordination

A self-loading concrete mixer can combine loading, mixing and transporting functions that might otherwise require separate items of plant. This can simplify equipment coordination on some projects.

However, a self-loading mixer does not necessarily eliminate the need for other equipment. Materials still need to be delivered and stored, and additional plant may be required to place concrete at its final location. Depending on the project, this may include concrete pumps, dumpers, conveyors or other placing equipment.

The suitability of on-site mixing should also be considered in relation to concrete quality requirements. Concrete must be produced, transported, placed and controlled in accordance with the relevant specification and applicable standards. Reliable batching and proportioning of constituent materials, control of water content and appropriate quality assurance procedures are important where structural or other specified concrete is being produced.

Ready-mixed concrete remains an effective solution for many projects, particularly where large volumes are required continuously and suitable delivery access is available. On-site mixing may provide greater flexibility where demand is intermittent, delivery access is difficult or projects are located at a significant distance from batching facilities.

[edit] Comparing the costs of buying and renting

The decision between buying and renting should be based on total cost and expected utilisation.

For rented equipment, costs may include:

hire charges;
delivery and collection;
fuel or energy;
insurance;
operator costs;
cleaning and damage charges; and
the cost of extended hire periods.

For owned equipment, costs may include:

purchase price;
financing costs;
depreciation;
maintenance and repairs;
replacement parts;
insurance;
fuel or energy;
storage;
inspections and compliance;
operator training and employment; and
the residual value of the equipment.

The calculation should also consider the opportunity cost of capital and the likely period of ownership. A machine that is inexpensive to purchase but has high maintenance requirements or poor utilisation may provide less value than rented equipment. Conversely, repeated rental costs can become significant where equipment is required consistently over several years.

A simple assessment should consider:

how often the machine will be used;
the expected number of operating hours;
the volume and frequency of concrete production;
the duration of individual projects;
the availability and cost of ready-mixed concrete;
site access and transport requirements;
the availability of suitable operators and maintenance support; and
whether the equipment can be used on future projects.

[edit] Project applications

Self-loading concrete mixers may be suitable for a range of projects where mobile, on-site concrete production is required.

Residential and housing projects may require relatively small quantities of concrete at different stages for foundations, floors, drainage and external works. A mobile mixer can provide flexibility where requirements are intermittent.

Road and infrastructure projects can extend over large areas, with concrete required at dispersed locations for drainage structures, foundations, kerbs and other works. Mobile equipment may reduce the distance between concrete production and the point of use where conventional supply arrangements are impractical.

Remote projects may also benefit from on-site concrete production where access to batching facilities is limited or delivery distances are significant. However, the logistics of transporting and storing cement, aggregates, water and other materials must still be considered.

The appropriate equipment strategy depends on the scale of the project, concrete specification, required output and local conditions. A self-loading mixer is not necessarily the most suitable option for projects requiring large continuous pours or high production volumes.

[edit] Selecting equipment for ownership

Where purchasing is considered appropriate, the selection process should assess both the machine and the anticipated operating environment.

Required production capacity should be established using realistic hourly and daily demand rather than nominal drum capacity alone. The machine should also be compatible with site access, terrain, available working space and transport arrangements.

Maintenance and technical support are important considerations because equipment downtime can disrupt concrete operations. The availability of replacement parts, suitably trained operators and competent maintenance personnel should be assessed before purchase.

Safety requirements should also be considered. Operators require appropriate training, and arrangements may be needed for inspections, maintenance and the safe loading and operation of the equipment. The risks associated with moving plant, material handling, rotating machinery and concrete production should form part of the project's wider health and safety management arrangements.

[edit] Making the decision

Neither buying nor renting is universally the better option. Renting can provide flexibility and reduce capital expenditure where equipment requirements are short-term or uncertain. Buying may provide better value where a machine can be used regularly and efficiently across several projects.

The decision should be based on anticipated utilisation, whole-life costs, project requirements and the availability of alternative concrete supply methods. Site conditions, required concrete output, access, quality requirements and future workloads can all influence the outcome.

A self-loading concrete mixer can provide a flexible method of producing and transporting concrete on suitable projects, but its advantages should be assessed alongside the costs and practical requirements of ownership, rental and conventional ready-mixed concrete supply.