Volumetric concrete mobile plants

Volumetric concrete mobile plants

Volumetric concrete mobile plants, which are otherwise known as Volumetric Concrete Mixers or Mobile Concrete Batching Plants, transport the different components of concrete in a dry state, and mix them together when they arrive at the site where they are required.

Although volumetric concrete mixers were introduced in the 1950s, they became commonly used in the 1990s when new technology made them more efficient and easier to operate.

The alternative method that is used to transport concrete is a Drum Mixer which is used to transport concrete that has been mixed at a batching plant and continues to be mixed as it is transported to the site where it will be used.

Temporary weight limit

Between December 2014 and March 2015, the Department for Transport (DfT) ran a consultation on a proposal to remove certain exemptions from Heavy Goods Vehicle (HGV) operator licensing. One of these exemptions was an engineering plant exemption for vehicles that delivered materials as well as processed them at a plant. At the time of the consultation, volumetric concrete mixers fell within this exemption, and did not need to meet the normal HGV rules. This meant, for example, that volumetric concrete mixers did not need to meet the HGV vehicle weight limit (which was 32 tonnes for 4-axle rigid vehicles).

In the July 2015 Summary of Responses document following the consultation, the DfT reported that “there was a broad consensus” that vehicles that carry and deliver a product should be operated under an operator’s licence:

4.2: Responses have confirmed that there is a concern that there can be competition between regulated vehicles and nonregulated vehicles operating in the same market. The most obvious example is between rotary cement mixers and volumetric concrete mixers where both vehicle types carry and deliver similar products, but under different regulatory regimes.

4.3: It is noted that there was a broad consensus that for vehicles that both carry and deliver a product there is little justification for these vehicle not being operated under an operator’s licence.

In December 2017, the DfT announced that this exemption would be removed:

Operators of these vehicles will be required in future to have licences for the use of the vehicles based on the same process that applies to mainstream large goods vehicles, including barrel concrete mixers and tipper trucks.

A temporary weight limit was also put in place for volumetric concrete mixers, with a proposed duration of this arrangement of between 7 and 10 years. This weight limit differed depending on the vehicle configuration, but a limit of 38.4 tonnes was put in place for 4-axle rigid vehicles.

In April 2018, Jesse Norman, the then transport minister, announced that the temporary weight regime will be for a period of 10 years. At the end of this period, in 2028, volumetric concrete mixers will be subject to the same weight limits as other HGVs.

I also asked for views on the MCBP industry proposal for an amendment to the “special types” rules that would enable MCBP to continue to operate outside standard legal gross vehicle weight limits, but within standard axle weights, in order to maintain similar payloads to current operations.

Having considered the views expressed, I have decided not to progress such an arrangement. Derogations from the standard weight limits are generally permitted exclusively for the carriage of indivisible abnormal loads or equipment. There is no compelling case to permit such a derogation for the carriage of concrete constituents. MCBP operating weights should, at the end of the temporary arrangement outlined above, converge on the legal weight limits applicable to other heavy goods vehicles.

Lower Carbon Construction Vehicle APPG

In December 2021, the Lower Carbon Construction Vehicle APPG was set up to campaign for the temporary weight limit to remain in place in 2028:

To campaign for local construction firms to continue to use volumetric concrete mobile plants (VCMs) at 38.4 tonnes on 4 axles and 44 tonnes on 5 axles to provide concrete services in every community with zero waste, fewer journeys and a lower carbon footprint.

The APPG has argued that the proposed 2028 weight limit will mean more volumetric concrete mixers on the roads, and increased carbon costs.

Responding to a parliamentary question (PQ13647, answered 2 March 2021), Transport Minister Baroness Vere of Norbiton confirmed that the Government was aware that the eventual industry changes may mean additional vehicle miles are required to offset lower permissible weights per vehicle. She said:

Further to the response to HL13350, the permitted maximum laden weight of volumetric concrete mixers has not been reduced. A temporary arrangement to enable market adjustments to the operation of the vehicles complying in practice to the standard weights applicable to heavy goods vehicles has been put in place. The longer-term market adjustments may include the same vehicle or other vehicles types travelling for additional distances.

Similarly, the issue of additional vehicle miles being required due to the 2028 change – and therefore possibly resulting in more fuel-use and emissions – was raised in a separate PQ (PQ62817, answered 28 October 2021) as follows:

Mr Tanmanjeet Singh Dhesi (Labour)

“To ask the Secretary of State for Transport, whether he plans to produce an environmental impact assessment on the potential additional lorry miles that may occur as a result of the weight restrictions on volumetric concrete mobile plants from 2028.”

Trudy Harrison (then Transport Minister)

“Following regulatory changes in 2017, a temporary regime was put in place to allow a limited number of volumetric concrete mixers (VCMs) to temporarily operate at higher than standard weights until 2028 at the latest. An impact assessment was undertaken at the time of the regulatory changes in 2017 and there are no plans to produce an additional environmental impact assessment.”

Further reading

All-Party Parliamentary Group for Lower Carbon Construction Vehicles, 17 May 2023

Batched on Site Association, BSA statement on volumetric mixer decision, 9 April 2018

The Construction Index, Aggregates lobby group sets up concrete division, 9 June 2023

The Construction Index, Volumetric mixers expand Cemfree possibilities, 29 January 2020

The Construction Index, Ten-year transition for mobile concrete batching plant regs, 6 April 2018

Mixamate, Launching the All Parliamentary Group for Lower Carbon Construction Vehicles, 14 December 2021

Official IRTE Journal, Transport Engineer, DfT clamps down on concrete trucks, 5 January 2018