Criticisms of whole life costing WLC is also not an exact science, as, in addition to the difficulties inherent in future cost planning, there are larger issues at stake. Also, WLC requires a different way of thinking about cash, assets and cash flow.
Many organisations are simply not geared up for this adjustment. Perhaps the most crucial reason is the difficulty in obtaining the appropriate level of information and data.
There is a lack of available data to make the calculations reliable. The Building Maintenance Information BMI define an element for occupancy cost as expenditure on an item which fulfils a specific func- tion irrespective of the use of the form of the building. The system is dependent on practitioners submitting relevant data for the benefit of others.
The increased complexity of construction means that it is far more difficult to predict the whole life cost of built assets. There is no comprehensive risk analysis of building com- ponents available for practitioners, only a wide range of predictions of estimated life spans and notes on preventive maintenance — this is too simplistic, there is a need for costs to be tied to risk including the consequences of component failure.
There is no guarantee that the selection of so-called high-quality materials will result in low life cycle costs. There is also a lack of taxation incentive, in the form of tax breaks, etc. WLC, by definition, deals with the future and the future is unknown. Increasingly, obsolescence is being taken into account during procurement — a factor that is impossible to control since it is influenced by such things as fashion, technological advances and innovation.
An increasing challenge is to procure built assets with the flexibility to cope with changes. Thus, the treatment of uncertainty in information and data is crucial as uncertainty is endemic to WLC. Another major difficulty is that the WLC tech- nique is expensive in terms of the time required. This difficulty becomes even clearer when it is required to undertake a WLC ex- ercise within an integrated real-time environment at the design stage of projects.
Forecasting costs and value 85 In addition to the above changes in the nature of development, other factors have emerged to convince the industry that WLCs are impor- tant, principally sustainability. This method was first developed and introduced into the manufac- turing sector in America, immediately after the Second World War. The principal objective of this technique is to gather together the principle stakeholders of a new project in a workshop over a four or five day period.
The process is managed by a value management practitioner, who can be a quantity surveyor. This may be the only occasion when all of the stakeholders of a new project meet together to discuss the outcomes. The process involves the analysis of the re- quired functions of a new project and then the investigation of how these function may be achieved Figure 2.
Concentrating of func- tions allows items that do not contribute to the identified functions, referred to as waste, to be removed from the design. The traditional approach to determining the cost of a new project is to apply costs to the product — the various parts of a new building.
Value management takes a sideways step and applies costs to the required functions and then looks at ways, through design and con- struction, for providing functionally optimised building projects. It is broken down into three phases: Pre-Study, where members of the value management team become familiar with the project parameters.
Next comes the Value Study phase, which is itself broken down into six phases that take the workshop through a structured process, the characteristics of which are: Functional analysis. Defining, classifying and establishing the worth of a function or functions which is at the heart of the value management process.
The definition of function can be problematic; experience has shown that the search for a definition can result in lengthy descriptions that do not lend themselves to analysis. In ad- dition, the definition of function has to be measurable. In order to establish some sort of hierarchy, functions need to be classified into primary needs or supporting function wants. Complete Data Files. Evaluation Factors. Study Scope. Data Models. Finalise scope. Function Analysis Phase Identify Functions.
Classify Functions. Function Models. Establish Function Worth. Cost Functions. Establish Value Index. Select Functions for Study. Select Ideas for Development. Development Phase Benefit Analysis. Technical Data Package. Implementation Plan. Final Proposals. Presentation Phase Oral Presentation. Written Report. Obtain Commitments for Implementation. Implement Changes. Monitor Status. Out of the list of functions emerges the highest order function that can be defined as the overall reason for the project and meets the overall needs of the client.
Or, in other words, seems to have a high concentration to the total project cost in relation to the function. Following on from this the creative phase will concentrate on these functions.
Having estab- lished the worth and the cost, the value index can be calculated. The benchmark is to achieve a ratio of 1. Indeed, the number of contracts based on a bill of quantities has declined sharply over the past 20 years or so. Nevertheless, the bill of quantities remains unsurpassed as a model on which to obtain bids in a format that allows: ease of comparison between various contrac- tors, transparency, an aid to the quantity surveyor in valuing varia- tions, calculating stage payments and the preparation of the final account.
What is more, the ability to measure, quantify and analyse the items of labour, materials and plant necessary to construct a new project is still a much sought after skill and many would argue that it is the core of the quantity surveying profession.
There are a number of situations that require a quantity surveyor to measure and record dimensions from both drawings as well as on site, depending on the stage of the project.
In order to standardise measurement rules and conventions, there are a number of standard codes and methods of measurement that are available. These are outlined below. The RICS code of measuring practice, 6th edition According to the Royal Institution of Chartered Surveyors RICS the purpose of the code is to provide succinct, precise definitions to permit the accurate measurement of buildings and land, the calcula- tion of the sizes areas and volumes , and the description or specifica- tion of land and buildings on a common consistent basis.
GIA is the area of a building measured to the internal face of the perimeter walls at each floor level. NIA is the usable area within a building measured to the internal face of the perimeter walls at each floor level.
Note: An area is usable if it can be used for any sensible purpose in connection with the purposes for which the premises are to be used. It was an attempt to bring uniformity to the ways by which quantity surveyors measured and priced building works.
The sev- enth edition appeared in as a joint publication between the RICS and the Building Employers Confederation and was revised in The current, third edition, was published in This, in turn, reflects the different ways in which building and civil engineering projects are organised and carried out. Building work comprises many different trades, whereas civil engineering works consist of large quantities of a comparatively small range of items. For example, when mea- suring excavation using SMM7 it is necessary to keep excavation, earthwork support and working space as separate items, whereas when using CESMM3 all these item are included in a single item of excavation.
The UK standard method of measurement of building works SMM7 has been used as the basis for the preparation of methods of mea- surement that are used in Malaysia and Hong Kong. On larger contracts the measurement will be divided between several surveyors and it is important that double measurement or omission of items do not occur.
For example, the surveyor measuring the external walls will measure the various items gross, in other words, without deduction for any door or win- dows. However, the surveyor measuring the doors and windows must deduct the area occupied by doors and windows, as well as measuring the work to the sides the reveals , the cill and the head of the door or window opening. Similarly, the surveyor measuring the roof must know where the demarcation of the roof and the external walls are and that roof measurement includes not only the roof structure, but also the coverings and the rainwater goods.
The taking off sched- ule will also include the start and anticipated completion date of the various groups.
When using this approach, the measurement and bill process have three stages: 1. The measurement stage. On completion of the measurement the quan- tities are calculated ready for the next stage. The abstract stage. The process by which the measured items together with the associated quantities are transferred from the dimension paper to an abstract where all like items are grouped together and they are arranged in the order that they will appear in the bill of quantities.
The draft bill stage. Using the traditional system the items are now transferred from the abstract to the draft bill, where items are written out in full.
This draft bill now has to be printed in the final bill of quantities format. It can be seen from the above notes that the traditional approach is labour-intensive and therefore little wonder that various systems, increasingly based on IT solutions, have been developed to speed up the process.
Nevertheless the ability to measure and abstract items is a skill still used by the modern quantity surveyor throughout pre and post-contract stages of a project and one that is highly sought after by the industry on both demand and supply sides. Trade-by-trade This method involves organising the measuring of the quantities in the same order as the final presentation. That is, each surveyor has the responsibility for measuring a complete trade and is issued with a complete set of drawings and other information relating to the project.
In addition, as each section is completed, it can be processed. Over the years there have been other bill formats developed, such as operational, but these have never been widely adopted by the UK construction industry. During the measurement period it can be expected that the informa- tion on drawings and schedules will be revised and updated many times, it is therefore important that the quantity surveyor always uses the most up-to-date information when preparing the bill of quanti- ties.
Almost every day will bring an updated set of information. It is of course impossible to keep on including revisions in bills of quantities indefinitely, or otherwise the bills would never be produced, therefore the quantity surveyor has at some point to draw a line in the sand and base the measurement on what information is currently available.
Any subsequent revisions to drawings, schedules, etc. However, in order to fully un- derstand and appreciate the potential problems in the measurement process a thorough knowledge of measurement conventions is essen- tial as measurement is used by the quantity surveyor not just during the bills of quantity stage, but also during measurement and prepara- tion of interim valuations and the final account. The traditional ap- proach to measurement involves starting with recording dimensions on traditional dimension or taking off paper, see Table 3.
Measurement and quantification 1 2 3 4 1 2 3 4 Table 3. This description will appear in the final bills of quantities. Finally, as illustrated later, the right-hand side of the dimension column is reserved for what is referred to as the waste calculations. A well signposted set of dimensions can save a lot of time in circum- stances where work has to be remeasured at the final account stage. When taking off quantities in accordance with SMM7 the units of measurement will be: cubic metres, square metres, linear metres and numbered items.
In addition, there are some items that are required to be recorded as items, which are descriptions without a quantity, for example testing drainage.
When recording dimensions on the taking-off paper the order in which the dimensions are recorded is always length, width and depth as noted in Figure 3. SMM7 The column. At the end of the tak- 2. Once again two 2. When there is more that one The description is composed in ac- dimension that relates to a sin- cordance with the SMM7.
Shorthand gle description, the dimensions is often used, for example: should be bracketed together. Waste calculations Waste calculations reduced Length It may be tempting, particularly if learn- ing the process, to use pencil, for ease of correction; however, this can cause embarrassment if the accuracy of the dimensions are called into question at some future date. If an error is made during the measurement process then there is a procedure that should be followed.
In order to avoid repetition, a description that refers to the same dimensions can be anded-on as illustrated in Figure 3. Adds and deducts Figured dimensions, that is dimensions shown on the drawings and scaled dimensions, that is dimensions scaled off drawings using a scale rule, can be used when measuring quantities; however, figured dimensions always take preference.
During the measurement pro- cess it is often necessary to add This is done by using 2. As the item to 2. A common fault when using Adds and Ddts is to continue the sequence over the page to a different column. Never and-on over a page.
Figure 3. Frequently, this will occur when making adjust- ments for items such as windows and door openings, as illustrated in Figure 3. Using this 2. In the 2. Depending on circumstances the mean girth can be calculated from the internal or external face; in the following example the internal dimensions will be used.
Measurement and quantification Mean girth Note: using the internal As far as calculating Having mastered the basic measurement conventions it is now time to start taking off; but where to start? It is assumed that the group method is to be used to manage the tak- ing-off process, as described earlier in this section, starting with substructure. Substructure involves the measurement of all work up to and including the damp-proof course.
It includes a variety of trades such as excavation, concrete work and masonry. Top soil cannot be used for backfilling as it would, over time, cause damage to the substructure.
The usual default depth for topsoil is mm although it could be more than this and a test pit may be dug to accurately determine the actual depth. This can be quite easily done by weighting the levels as follows starting at the top left-hand corner of the site Note that the levels have been reduced internally by mm to allow for a mm thick bed of hardcore. The top of the hardcore bed when compacted will be covered or blinded with sand to prevent the damp- proof membrane, a layer of polythene sheet with a minimum thick- ness of 0.
It is important that the material used as hardcore is inert and free from chemicals, vegetable or other deleterious matter. It is a requirement of the Building Regulations that insulation is incorporated into the floor construction and in this case 50 mm thick rigid insulation board has been used.
The bottom of the trench excavation when completed will be compacted prior to the concrete being poured, this is to prevent the soil being incorporated into the concrete and weakening the mix. This is particularly important when reinforced concrete is being used, where it is common to blind the bottom of the excavation with a weak mix concrete before the reinforcement is placed in position.
There are clear health and safety issues here for the contractor, who must decide, having priced the item in the bills of quantities, whether he is actually going to use earthwork support on site. Excavation — sundry items There are some other common items in SMM7 relating to excavation that need to be discussed.
Working space Clause D It is measurable as a superficial item where there is less than mm between the face of the excava- tion and the work; all additional earthwork support, disposal, backfill- ing and breaking out are deemed to be included with the working space item. Working space Girth at this point multiplied by the height is used to calculate working space allowance Height This distance must be less than mm Figure 3.
When concrete and brickwork are measured later the quanti- ties of filling will be adjusted. Note cavity fill should be stopped at least mm below the base of the dpc. Adjustment for brickwork in trenches It is applied to both leaves of a cavity wall and lapped mm at joint in the dpc. It must not bridge or span the cavity.
However, the external skin is built in facings, a External face Facing bricks also provide a much superior finish. This is best done at draft bill stage. These include: excavating below ground water level, next to existing services and breaking out rock, reinforced concrete, etc.
Work is measured over all doors, windows and other openings, these being adjusted at a later stage. The theory is that it is better to overmeasure and then make deductions and adjustment later, rather than measure net. In this way, if items are missed then at least something has been included! SMM7 Section F deals with the measurement of masonry and includes brick and block walling, the unit of measurement is gener- ally the square metre.
Therefore a one brick wall will be assumed to be mm thick and a two brick wall mm thick. Bricks are delivered to site pre-packed on wooden pallets for easy unloading and bought by the thousand, except for specially made units. Bricks can be broadly categorised as follows: Common bricks: these are suitable for general building work where the finish is not important. Common bricks are made from clay and are cheaper than other alternatives. Facing bricks: facings come in a wide variety of finishes, colours, strengths and prices and are used typically in the external skin of cavity walls.
Also made from clay, facing bricks are weather resistant and generally finished with pointed joints. Engineering bricks: these bricks have low water absorption prop- erties and a high compressive strength.
Typically used in retaining walls, bridges and manholes. Measurement and quantification Calcium silicate bricks: sometimes referred to as sand lime fac- ings, these are of the more easily recognisable forms of facings made from sand, crushed flint and lime.
Walls of one brick thick and over can be built in common brick- work with facings on one side. In this case the facing brickwork is measured as extra over. Expansion joints In order to avoid excessive cracking 16 mm thick vertical expan- sion joints are required in brickwork, generally at 12 metre centres, whereas when using calcium silicate bricks the joints must be at 7.
The material used for expansion joints can be: Flexible cellular polyethylene Cellular polyethylene Foam rubber The joint is finished with a sealant at least 10 mm deep.
Dense blockwork Dense blocks are suitable for above and below ground situations and are made from cement, sand and crushed gravel. Lightweight blockwork Lightweight blocks include lightweight aggregates and are generally used for the internal skins of external walls or where a high degree of thermal insulation is required. They are lighter and easier to handle on site than dense concrete blocks with poor sound insulation qualities.
Mortar There are a variety of commonly used mortar mixes that should match the type, location and strength of the masonry. Therefore, a mortar mix of cement:sand would be classed as a strong mix whereas a mix of cement:lime:sand would be classified as a weaker mix.
Liquid plasticisers can be used in place of lime to improve mortar workability. It is common practice to insulate the partitions to reduce sound transmission. The joints are formed with nails. Internal walls A timber stud partition is a common form of construction Timber stud partition for internal partitions. They Number of studs may either be load bearing, in which case they will be formed 6. The head and sole plates are fixed directly to the ceiling Height 2.
Stud partitions can be covered with Head and sole plate 6. Noggings Studs mm centres 0. Adjustment for door opening In other words where some spe- cific method of fixing is specified Ddt by the architect or the engineer. Sundry items of masonry The following items are commonly met by the quantity surveyor when measuring masonry.
Apart from half brick skins in hollow walls, brickwork comes in three classifications from the SMM7 viewpoint, these are: Common brickwork, where the wall of whatever thickness is built entirely of common brickwork. Common brickwork with facework one side. For example: One brick wall in common bricks, ver- tical, English bond in gauged mortar facework and pointed one side in facings with recessed joint as the work proceeds.
Brick facework both sides, where both sides of the brickwork are fin- ished fair with facings or a fair face and pointing. It is therefore pos- sible to have a two brick thick wall, built from common bricks with facings both sides. Two brick wall in common bricks, ver- tical, Flemish bond in gauged mortar facework and pointed both sides in facings with recessed joint as the work proceeds. With the exception of closing cavities and bonding new work to existing, all labour such as rough and fair cutting, throats, mortices, etc.
Measurement and quantification One brick wall faced and pointed both sides Plan Extra pointing to the reveals is included in the item and not measured separately. Isolated piers According to SMM7 a wall becomes an isolated pier when the length on plan is less than four times its thickness. Conversely, when the length on plan exceeds four times the thickness then the classifica- tion is wall.
For example: mm mm 0. Tapering walls 1B Tapering walls have to be described and the aver- age thickness calculated. Chipboard is cheaper and quicker to lay as it comes in large sheets although a disadvantage is that maintenance and access to the floor space can be more difficult compared with board flooring. Concrete and steel are just as suitable for floor con- struction although these materials are mainly used in medium and high rise buildings.
The SMM7 requires that timbers in excess of 6 m are kept sepa- rate and described as such as timber in such lengths as this is dif- ficult to obtain and handle. To stop floor joists twisting and deforming it is usual to insert a line of strutting fixed at right angles to the joists.
Solid or herring- bone strutting can be used. Floor joists are generally spaced at mm centres and can either be built into the inner leaf of the cavity wall provided a good seal can be afforded to the cavity less common practice or supported in a galvanised steel joist hanger built into the wall.
In certain situations galvanised or stainless steel straps are required every 2 metres to provide restraint and prevent movement of the external walls. It may be necessary to incorporate sound insulation into the floor space.
One end is turned down and fixed into the cavity. For medium and high rise buildings it is more usual to have a flat roof covered with a high performance sheet finishing. Flat roofs are generally more problematic from a maintenance and life- cycle cost point of view. It covers measurement methodology including samples using NRM2 as a guide , highlights the complex aspects of a contractor's business, reviews the commercial and contractual management of a construction project, and provides detailed and practical information on running a project from commencement through to completion.
It provides a full breakdown of labour, plant and material elements, with labour rates updated. This 34th edition gives a strong development of prices for excavations and rail, and a general overhaul of prices through the book. In a time when it is essential to gain 'competitive advantage' in a sometimes turbulent market, this price book provides instant-access cost information and forms a one-stop reference.
Updates are available online at www. This can mean acting as consultant in a range of roles including cost and advisory services for budget setting to initiate a project, cost management through the design and construction phases, contract administration and acting as the client side project manager to oversee the entire building process. Following a number of positions with UK contractors he relocated to Australia and has worked with a number of developers and main contractors, as well as doing freelance work.
He is currently working in contracts management in Sydney. It covers all the items to be found in hard and soft landscape contracts, and forms an indispensable reference book for quantity surveyors, landscape architects, contractors and local authority managers — essential for compiling estimates, specifications, bills of quantities and works schedules — no matter what the size of the project being undertaken.
Please Note : This list is not the final book list. Fundamentals of Surveying By Roy S. Surveying or land surveying is the technique, profession, art and science of determining the terrestrial or three-dimensional positions of points and the distances and angles between them.
A land surveying professional is called a land surveyor. And also, related research seminar topics and journals for final year students in the quantity surveying department. Masters and Ph. All you need to do is to select your topics below and submit them to your supervisor for approval. Then after approval come back for your complete material. Do you need a copy of any complete project material?
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