• Measurement of Civil Engineering Works

    Overview

    Objectives for this tab are:

    To understand the need for Civil Engineering Standard Method of Measurement 4 (CESMM4)
    To be able to interpret (CESMM4)
    To become familiar with the scope CESMM4 measurement conventions

    Civil Engineering Quantities

    To reflect the nature of civil engineering work, the Institution of Civil Engineering published the first Civil Engineering Standard Method of Measurement (CESMM) in 1976.
    In 2012 the fourth edition (CESMM4) was published
    It would have been highly impractical to use a method of measurement similar to NRM2 to prepare a bill of quantities for the Millau viaduct illustrated below.

    Brick wall piers/projection
    Fig. The Millau viaduct

    Due to the scale and inherent uncertainties in civil engineering work, unlike NRM2 and building works, civil engineering work is subject to admeasurement (re-measurement) as work proceeds.
    Based on ‘measure and value.’
    An exception to this are Method Related Charges – discussed later in tab 12.2
    This appears not to affect the ethos of measuring quantities as accurately as possible.

    CESMM4

    CESMM4 does not deal with the measurement of;
    complex mechanical / electrical work,
    complex building work, or
    work seldom encountered in civil engineering.
    The above items should be itemised and described and the method of measurement stated in the Preambles to the bill of quantities.
    The use of provisional quantities is discouraged – provisional sums should be used.

    Class Z Simple building work

    Introduced in CESMM3, simple being defined as; a gate house or valve house.

    The trades included are somewhat limited e.g.
    Carpentry and joinery
    Insulation
    Window, doors and glazing
    Surface finishes, lining and partitions
    Mechanical & Electrical – fittings being measured separately

    Therefore, the q.s. has two alternatives when dealing with simple building work;

    Follow the advice of CESMM4 Clause 2.2
    Use NRM2 to itemised and described the simple building work with a note in the Preamble,
    or
    Use Class Z
    The criteria to use Class Z are;
    The building should be simple enough not to merit full NRM2 measurement
    It should be incidental to the civil engineering project

    CESMM4 is both contract and national standards neutral.

    Contract neutral means that CESMM4 can be used with a variety of contracts including; NEC4, ICE7, FIDIC, etc.
    As a result a 🔗 schedule has to be completed detailing the clauses and the terms of the contract that is to be used. The schedule is incorporated into the Preambles to the bills of quantities and referred to when necessary.
    National standards neutral ensures that reference to British Standards is largely eliminated from the bills of quantities
    Consequently, references to BS or other national standards must therefore be given on the drawings.

    Recording dimensions

    When it comes to recording dimensions and descriptions the conventions are exactly the same as described in Week One for NRM2.

    Access to ICE virtual library and CESMM4: Civil Engineering Standard of Method and Measurement

    This 📹 video explains how to access Books and Ebooks through the 🔗 GCU University Library website. In the Search box enter CESMM4 and click on the Available Online option. This in turn will take you on to the ICE Virtual Library site and access to the CESMM4, Sections 1-8 pdf.

    Activities

    1. In the context of a civil engineering project how should electrical installations be incorporated into a bill of quantities?
    2. As CESMM4 is contract neutral how is information on items such as; interim payments incorporated into the bills of quantities?
    3. What is ad-measurement?
    4. List the items of works specifically excluded from CESMM4

  • Interpretation of CESMM4

    Overview

    Objectives for this tab are:

    To be able to interpret CESMM4
    To become familiar with the scope CESMM4 measurement conventions

    Arrangement of CESMM4

    CESMM4 is divided into;

    8 Sections
    1 – Definitions
    2 – General principles
    3 – Application of work classifications
    4 – Coding and numbering of items
    5 – Preparation of the Bills of Quantities
    6 – Completion, pricing and the use of the Bill of Quantities
    7 – Method-related charges
    8 – Work classification (Classes A – Z) and
    26 Work classes

    Work sections / classes reflect the nature of civil engineering work and are arranged in portrait format - similar to NRM2

    Coding and numbering systems

    May be used to number items in the Bill of Quantities, for example;
    Earthworks; excavation for foundations; material other than topsoil, rock or artificial hard material; maximum depth: 1-2m (E324)

    maximum depth: 1-2m (E324)

    If code numbers are adopted they must not form part of the description but be placed in the item number column.
    Items are listed in descending order in the BQ

    List of principal quantities

    The list of principal quantities is prepared by the taker-off and should satisfy two requirements;

    To give the estimator an early feel for the scope of the work prior to commencing pricing
    To help the contractor’s pre-contract meeting with regard to size and type of contract when considering the application of the adjustment item.
    The list has no contractual significance, for example;
    1. Site clearance: 0.548 ha
    2. General excavation: 1709 m3
    3. Concrete: 537 m3
    4. Reinforcement: 28.71 t
    5. Pipework: 1073 m
    6. Roads: 1416 m2
    7. Masonry: 735 m2

    Definitions - Rock

    Unlike NRM2 which contains a standard definition of rock, rock is defined uniquely for each contract and included in the Preambles.

    Section E Grand Summary

    Sequence of BQ contents;

    Section A List of principal quantities
    Section B Preamble
    Section C Daywork schedule
    Section D Work items
    Part 1 General items
    Part 2 Etc.
    Part 3 Etc.
    Part 4 Etc.

    Grand Summary
    Fig. 4.1 The Grand Summary

    Adjustment item

    Similar to the Director’s adjustment item in NRM2
    Logic for inclusion somewhat different to NRM2
    CESMM4 allows for an Adjustment Item to be included in the Grand Summary
    Can be in the form of an addition or deduction.
    Will be paid or deducted in instalments in proportion to tender figure prior to the adjustment in the Grand Summary

    Activities

    1. Discuss the differences between CESMM4 MRCs and NRM2 Preliminaries.
    2. How is rock defined in CESMM4?
    3. Which section of CESMM4 deals with coding of bill items?
    4. What is the purpose of a list of principle quantities?

  • Method Related Charges (MRC)

    Overview

    Objectives for this tab are:

    Understand method related charges
    To apply method related charges to practical examples

    Method-related charges (MRC)

    Introduced in 1976 in CESMM1
    To apply method related charges to practical examples
    MRCs cover items the cost of which are;
    not considered proportional to the quantities of other work items, or
    have not been allowed for in the rates or prices of other work items

    Importantly:

    Unlike measured work, MRCs are not subject to re-measurement
    Additional MRCs can be inserted by the tenderers
    A contractor is not bound to adopt the methods inserted in bill

    Items should be fully described and identify;

    Time related charges and
    Fixed charges

    If fixed, the lump sum is only payable when the work itemised is completed.

    If ‘time-related’ the payments are spread out over the time taken to achieve completion of the work covered by the item.

    In some respects MRCs form a similar role to the Preliminaries of NRM2 (see Week 1 Tab 1.1).

    Some items, such as supervision, site transport, welfare, should not be designated as ‘fixed’ as there is no definable time when they could be said to be completed, other than the end of the contract

    The fixed and time related charges will be used by the engineer to pay the contractor by way of stage (monthly) payments.

    The tenderer is not bound to price MRC’s and can if preferred include the cost in the bill rates.

    Adjustment of MRCs

    MRCs can only be adjusted if the engineer instructs the contractor to carry out the work in a different manner using the following formula as follows;

    Adjustment of MRCs formula

    For example study the following scenario:

    On a new sea defence works involving 2000m3 of C40 concrete works, the Contractor includes in the Bill of Quantities the following Method-Related Charges:

    1. Erect on-site concrete batching plant: Fixed Charge £5,000

    2. Operate and maintain batching plant. Time-Related Charge: £5,000/week x 10 weeks @ £50,000

    3. Dismantle and remove batching plant: Fixed Charge £2,500

    The Contractor’s accepted programme showed concrete works taking 20 weeks, starting in Week 5 and finishing in Week 25, but did not show when the batching plant would be erected or removed. The Contractor’s billed rate for the provision of all C40 concrete was £50/m3.

    a. What effect on the payment of those charges would there be if the Contractor himself decided not to batch any of that 2000m3 of concrete on site and used all off-site ready-mixed concrete instead.

    b. What effect, if any, on payment of those charges would the following events have?

    i. In Contract Week 5, the Contractor erects his batching plant and starts placing C40 concrete. The Engineer then issues a variation increasing the volume of C40 concrete required from 2000m3 to 3000m3. The Contractor batches all that 3000m3 of concrete on site, which keeps his batching plant on site for 30 weeks.

    ii. In Contract Week 5, and before the Contractor has erected his batching plant or placed any C40 concrete, the Engineer issues a variation decreasing the volume of C40 concrete required from 2000m3 to 1000m3. The Contractor then decides not to batch any concrete on site and uses off-site ready-mixed concrete instead for all of that 1000m3 of concrete.

    The solution

    a. If the contractor opts to use ready mix instead of mixing concrete on site, then the payment for concrete would remain as if a batching plant was used.

    b. i) If the engineer issues an instruction to increase the volume of concrete, the contractor would be paid additional costs for the extra 1000m3 at the rate of £50/m3

    ii) In the case where the engineer decreases the volume of concrete by 1000m3 and the contractor decides to adopt another method, the contractor will still be paid on the basis of the contractor’s original MRC.

    Activities

    1. Explain the differences between preliminaries and MRCs.
    2. What are the implications for MRCs if the engineer instructs the contractor to carry out the works in a different manner to the one originally envisaged?
    3. Under what circumstances can MRCs be re-measured?

  • Class A General Items

    Overview

    Objectives for this tab are:

    To understand the main divisions or categories of general items in CESMM4
    To understand the nature of provisional sums

    CESMM4 has six divisions of items that can be included in Class A General Items bill:

    1. General items (bond and insurances);
    2. Specified requirements;
    3. Method-related charges;
    4. Provisional sums;
    5. Nominated sub-contracts, for work done on site,
    6. Nominated sub-contracts, for work done off site.

    Class A includes items such as;

    1: General Items, e.g. Performance bonds, Insurance for the works and Third party insurance.

    2: Specified Requirements cover accommodation and services for the engineer’s site staff, tests on materials, etc., and a range of temporary works that the engineer might wish to itemise. For example;

    Temporary Works
    The difference between temporary works the engineer itemises as specified requirements under Division 2 of the Class A bill, and the temporary works which a tenderer adds as method-related items under Division 3 should be noted.

    If the contractor is required in the specification general clauses to construct some temporary access road, then if the engineer itemises it as a ‘specified requirement’ in Division 2 the details of it must be fully described in the specification or contract drawings.

    If the engineer does not know how the access road should be constructed because he does not know what traffic the contractor will put on it, then he should not itemize it in Division 2 but leave it to the contractor to add in Division 3 as a method-related item, if he so wishes.

    3. Method Related Charges - see Tab 12.2

    Sometimes referred to as method related items as priced on fixed and time related charges

    4. Provisional Sums

    Provisional sums for defined work.
    Provisional sums for defined work shall be included where work is known to be required but the scope can’t be defined.
    Shall state the nature of the work, indicative quantities and the scope and extent of the works.
    Contractor is deemed to have made due allowances for programming, planning and pricing of the works.
    CESMM4 doesn’t have a definition of undefined work – included with general contingencies.
    Provision for general contingencies (Undefined provisional sum) shall be made by giving a Provisional Sum in the Bills of Quantities.
    A Provisional sum for general contingencies may be included in the Grand Summary.
    Grand Summary
    Fig. 4.1 The Grand Summary

    Provisional Quantities

    The use of provisional quantities is discouraged by CESMM4.
    Used prior to CESMM1 – thought to lead to contractors loading rates – later used in re-measure
    Specific items of uncertainties in design – insufficient detail to take-off quantities
    Should be included in General Items as a Provisional Sum.

    5. & 6. Nominated Sub-contractors

    As CESMM4 is contract neutral, the appointment of sub-contractors will be in accordance with the form of contract used.
    Some forms of contract still allow for the appointment of nominated sub-contractors.
    Nominated sub-contractors are allowed for by the inclusion of a Prime Cost Sum.
    Followed by items for Labours, Special Labours (if applicable) and profit.

    In conclusion

    Class A – General items is an important first part of a bill of quantities based on CESMM4.
    Class A can contribute a significant cost contribution to the total cost of the project.
    The demarcation between MRCs and Class A; Specified requirements should be noted.

    Activities

    1. Explain the differences between defined provisional sums and contingencies.
    2. How should provision be made in a civil engineering bill of quantities for works to be carried out by sub-contractors?
    3. List some typical items that could be found in Division 1 of Class A.
    4. What is a Performance bond?

  • Class E Earthworks

    Overview

    Objectives for this tab are:

    To understand the nature and extent of CESMM4 Class E Earthworks.
    To appreciate the definitions used in CESMM4 relating to excavation levels.

    Note: All earthworks associated with roads and pavings are included in Class E

    Section 1 – Definitions

    Unlike building measurement where terms such as; reduced level, formation level and ground level are used when measuring excavation without much consideration. CESMM4 is completely unambiguous in regards to excavation level terminology, using the following terms; – see figure 5.1

    Original Surface: the surface of the ground before and work has been carried out. This definition refers not to virgin, untouched ground but ground on which no work has been carried out on the contract being measured. The sight the contractor sees when he /she walks onto site.

    Final Surface: the surface to which excavation is to be carried out. Final Surface is the level as defined on the drawings where the excavation is completed. Soft spots or any other excavation below this level would be described as ‘below the Final Surface’.

    Commencing Surface: the surface in relation to a BQ item before any work by the item has been carried out.

    Scenario
    During the works, excavation is carried out leaving the surface in its Final Position. Between the Original and Final Surfaces the contractor may do work covered by more than one bill item for example; general excavation before excavation for pile caps.

    The surface that is left after the work in one bill item is complete is the Excavated Surface for that item and the Commencing Surface to the next one, if there is one.

    Final Surface is the level shown on the drawings at which excavation finishes. Any work below this level, say for soft spots etc. is excavation below the Final Surface.

    excavation level terminology
    Figure 5.1

    Where only one type of material is encountered in an excavation the Commencing Surface is always the top surface prior to excavation and the Excavated Surface is always the bottom surface after excavation, unless separate stages of excavation are expressly required.

    Complications can arise, when the excavation penetrates through more than one type of material, e.g. rock. The top of the excavation is the Commencing Surface and the bottom is the Excavated Surface, no matter how many layers of different materials lie between the two.

    The maximum depth of the excavation of an individual layer of material in accordance with CESMM4, Paragraph 5.22 is the maximum depth of the excavation, even though the depth of the layer is significantly less. See sample bill of quantities - figures 5.2 and 5.3.
    Class E does not divide excavation into depth bands but according to total depth, for example;

    Breaking out concrete or other hard materials are dealt with as illustrated in figure 5.4

    ????
    Figure 5.2

    General Excavation

    E415 Topsoil maximum depth; 2-5m m3 153
    E425 Material other than topsoil, rock or artificial hard material depth; 2-5m m3 17,900
    E435 Rock maximum depth; 2-5m m3 600

    Figure 5.3

    Breaking out;
    General Excavation
    E444 Mass concrete exposed at the Commencing Surface maximum depth; 1-2m m3 20
    E454 Reinforced concrete not exposed at the Commencing Surface maximum depth; 1-2m m3 36

    Figure 5.4

    Activities

    1. How is rock defined in CESMM4?
    2. How is contaminated ground dealt with in Class E?
    3. Is compacting and / or trimming the surface of excavation measureable in Class E?
    4. It is quite common for civil engineering works to be carried out in open water – how does CESMM4 accommodate this?

  • Worked Example - Bored Cast-in Place Piling

    Overview

    Objectives for this tab are:

    To understand the CESMM4 rules for measuring piling
    To apply CESMM4 Class P, Q and E to a practical example

    Classes P (Piling), Q ( Piling Ancillaries) and E (Earthworks)

    Firstly study drawings 🔗 A/01/01 and/02
    The drawings show the layout of 15 bored cast-in-place of various sizes and depths.
    Two of the piles required enlarged bases.
    Piles of a different diameter and measured separately
    CESMM4 has two classes dealing specifically with the measurement of piling; P & Q.
    Also shown is the detail of the pile cap.
    The solution to this problem is shown on the attached dimensions sheets 🔗 (column nos. 1 – 6)
    Note that the setting out and measurement conventions are the same ones used for NRM2 and that the approach to measuring piling is largely similar in CESSM4 and NRM2.

    In particular that note of the following:

    Measuring piling

    The number of piles has to be stated as it allows the piling contractor to calculate how many times the piling rig needs to be moved around the site.
    Cutting of the tops of piles and preparing the pile head.

    Note that when using NRM2 this item in included with the Earthworks section.
    Obstructions.

    The inclusion of a number of hours for dealing with obstructions means that a bill rate will be established for this item if it is needed.
    Provision and placing of concrete

    The provision of concrete may be included, by the contractor, as a MRC.

    Activities

    1. Why, when measuring bored cast in place piling do three bill items have to be included?
    2. When measuring piling using NRM2, how is surplus excavated material measured?
    3. How is the possibility of encountering obstruction when boring piles allowed for?

  • Learning Outcomes

    On completion of this chapter you should be able to;

    understand the need for Civil Engineering Standard Method of Measurement 4 (CESMM4),
    interpret (CESMM4),
    become familiar with the scope CESMM4 measurement conventions,
    understand method related charges,
    apply method related charges to practical examples,
    understand the main divisions or categories of general items in CESMM4,
    understand the nature of provisional sums and
    apply CESMM4 to a practical example.