Concrete batching plants

This publication is intended for Valuation Officers. It may contain links to internal resources that are not available through this version.

1. Introduction

As a class Concrete Batching Plants are the responsibility of the Mineral Valuer.

This Section deals with the principles to be followed in the valuation of hereditaments, which comprise of or include concrete batching plants. It is also applicable to Mortar and Lean Mix Concrete Plants, which are essentially similar to concrete batching plants.

2. Method of valuation

In the absence of evidence of rack rents, and because of the specialised nature of concrete batching plants, comparison with other rented hereditaments is precluded. Therefore the contractor’s method of valuation is used to value the buildings, rateable plant and machinery and site works etc. However, the major item of value at a concrete batching plant is often the site and for this item careful consideration of the available rental and comparable evidence must be undertaken.

3. General description of concrete batching plants

The function of all concrete batching plants is to produce concrete, which can be delivered ready for use and accurately mixed to predetermined specifications. Similar style plants are used to produce mortar and lean mix concrete. The design of batching plants has developed progressively over the years and changes have often been the result of environmental and other considerations rather than product specifications.

A typical tower type concrete batching plant consists of a feed hopper and conveyor which is used to transport aggregates to a series of storage hoppers which are normally a free standing separate item but at some plants are located at the main structure. The main tower will usually consist of a cement silo with small aggregate hoppers located below. The batch weigher, with the delivery chute leading from it, is mounted beneath the aggregate hoppers and silo. The mixer vehicle will normally reverse beneath the plant for loading with the required quantity of concrete mix. At many plants additional cement silos have been added alongside the batcher tower.

Modified versions of these plants are the predominant style of batching plant but there are also a number of plants which consist of a large piece of machinery along the centre of which, totally enclosed, runs a conveyor. Situated above and to the sides of the conveyor are a series of aggregate hoppers, which are normally loaded by means of a small feed hopper and radial conveyor belt.

Cement silos are normally filled from cement tanker lorries with the cement blown up to the silos or storage tanks by compressed air generated either in a compressor at the plant or fixed to the cement tanker lorry.

The aggregates are usually stored in hoppers but at most plants additional supplies are stored at ground level. A common feature at the sites is a ‘wash-out bay’ where the returning mixer lorries are cleaned. Some of these bays are very basic but others have facilities for reclaiming the aggregates by discharging into concrete pits and tanks for dealing with the liquids resulting from the washing out.

Where there is a demand for ‘lean mix’ or ‘special mix’ it is normal practice to incorporate a mixing plant with the batching plant. The mixing plant may be of the pan type or horizontal fixed drum type. In some circumstances the mixing plant is fixed directly below the batching plant delivery point but it is more usual for it to be situated on separate supports alongside the batching plant thus maximising the available headroom at the batching plant delivery point.

4. Plant and Machinery

A concrete batching plant is not a named item in the relevant Plant and Machinery Regulations and thus only those parts or items of plant and machinery which are named and which fulfil the requirements of the relevant Regulations will be rateable.

Items of plant and machinery such as silos bins and hoppers should be considered for rateability as they are all named items in Class 4 Table 4. However many of these items at concrete batching plants may be excluded from rateability as having a total cubic capacity of less than 400m3 and being readily capable of being moved without the substantial demolition of any surrounding structure (Class 4(d)).

Exclusion of items by reference to their size only has application to items listed in Table 4, and items included in Table 3 such as foundations, settings, fixed gantries supports and platforms will be rateable subject to the exclusions (a) - (c) to the Class. In order to be rateable all items named in Class 4 must be, or must be in the nature of a building or structure. Guidance on the “structure test” can be obtained from Cardiff County Borough RA and AC v Guest Keen Baldwins Iron and Steel Co. Ltd (1949 CA RIT 2) and from RM 4:3.

Plant must be considered on its merits against the requirements of the Regulations having regard to any alterations or additions that may have been made and as to whether, if not the whole item, any part of it may be rateable as an item listed in Class 4 (subject to the exclusions (a) - (d)).

Compressors are used for the generation of pneumatic power and for pumping cement from the delivery tank. Air compressors providing pneumatic power will be rateable as being named items in Class 1 Table 1 together with such accessories as are specified in the List of Accessories such as storage cylinders (air receiver) and pipes (main supply but not branch service piping).

Electrical power plant should also be considered for rateability under the provisions of Class 1.

5. Site

A major item to be valued at a concrete batching plant is likely to be the site.

The use of land for a concrete batching plant falls within class B2 of the Town and Country Planning (Use Classes) Order, 1987 (As Amended) (SI 1987 Number 764) and care must be taken when considering any comparable rents that they are for land within the same General Industrial Class. In industrial or developed areas there sometimes exists considerable variation in value between B2 uses and B8 land used for general storage purposes.

For plants located away from quarries in industrial locations regard should be had to the evidence of any rents passing and close liaison will be necessary to ensure uniformity with any other comparable industrial properties in the locality. Care should be taken when dealing with site improvements to ensure that they are not included in the site rent passing which may be for an improved or bare (unimproved) site. Under this head there may be site concrete, ‘wash out’ and drainage facilities, fencing and flood lighting in addition to normal site services. The extent and specification of site concrete may have a significant effect on the overall valuation of a concrete batching plant and particular care must be taken to measure both the area and quality of concrete. It has often been found that although the original demise of a site for erection of a concrete batching plant includes existing site concrete this is often inadequate for the expected traffic of heavy goods vehicles and is replaced with high quality reinforced concrete during the construction of the site.

In localities where a market exists for general industrial land on a unit area basis the precise ascertainment of the site area occupied may be of great significance. It is recommended that, where a defined site area exists, the site should be carefully measured.

For plants located at quarries, marine wharves and rail depots there may be evidence of site rents where the batching plant is in the occupation of a different company or a different operating company within the same overall group. However, care should be taken in considering such evidence, as almost without exception there will be a contractual arrangement governing the supply of aggregate or possibly cement to the batching plant. These are commonly known as vending agreements and their existence is seldom noted in lease clauses. Concrete batching plants are often located on railway land and in certain circumstances such leases may require the occupier to bring in a specified tonnage of aggregate by rail with penalties if this is not met. It is unusual to find direct evidence of site values for batching plants located at and in the same occupation as the quarry. In these circumstances there should be a uniformity of approach with separately occupied concrete plants. It is often the case that the concrete company whilst being part of the same parent group is a separate operating company. In such cases there should be separate assessment of the respective hereditaments unless the actual circumstances at the site require a different approach.

Batching plants normally supply an area within 10 to 12 miles of the site (less in dense urban areas) and it will be appreciated that plant closures or new plants opening within this area may be relevant valuation factors in accordance with LGFA 1988 Schedule 6 Para 2(7).