Time : GHA wants 386 flats to be finished whithin 7 months which means 1.8 (lets say 2) flats must be done per day. Labour – for each flat there must be a team of 5 skilled men and if we want 2 flats to be done every day then we need at least 10 skilled men, 2 groups of 5.Factors affecting labour output and cost Job-site productivity is influenced by many factors which can be characterized either as labor characteristics, project work conditions or as non-productive activities.
The labor characteristics include:age, skill and experience of workforceleadership and motivation of workforceThe project work conditions include among other factors:Job site accessibility.Labor availability.Equipment utilization.Contractual agreements.The non-productive activities associated with a project may or may not be paid by the owner, but they nevertheless take up potential labor resources which can otherwise be directed to the project.
The non-productive activities include among other factors:Rework for correcting unsatisfactory workTemporary work stoppage due to inclement weather or material shortageTime off for union activitiesAbsentee time, including late start and early quitsNon-working holidaysStrikes Factors affecting material costs In every kitchen they want to replace : 1 sink, 4 cupboards & drawers, all worktop replaced.So the factors that may affect material cost areNumber of kitchen units to be fittedType of Kitchen worktopsKind of kitchen doors and drawersCost of other appliancesInstallation chargestransport to the siteStorage on site An allowance for wastage, which will vary according to the type of material but on average, is about 10%. This wastage can be attributed to items such as theft, breakages, misuse and mistakes during useSubcontract enquiries abour costs can arise in two areas. On-costs associated with the Working Rule Agreement and certain Overhead Costs incurred by their Employer. Other costs which may be specific to a particular project and therefore variable with each project are usually priced within the Preliminaries section of the Bill of Quantities.
The principal on-costs are as follows:Overtime payments Holidays Guaranteed week Travelling, fares and lodgings Sickness and injury benefit Retirement and death benefit Tool allowance Construction Industry Training Board (CITB) levy A levy paid to the training board to fund the training of new operatives and the development of new skills. Other items Employer’s liability insurances Additional payments for intermittent responsibility Health and welfare provisions EquipmentAll equipment will require some or all of the following maintenance on a regular basis if it is to continue operating at optimum levels:grease, replace loose or damaged parts, change filters,top up with fuel, top up with water, charge the batteries Failure to do so will not only increase the incidence of breakdown and reduce the machine’s efficiency but will also cause lost production.Effective maintenance is expensive and requires workshops, depot facilities, experienced staff, etc. The contractor should implement a system of planned maintenance, which can be divided into either preventative or corrective options.Planned preventative maintenance requires the implementation of regular procedures aimed at reducing wear, maintaining the plant in good working condition and preventing unseen stoppages. The main actions are as follows:daily servicing and superficial inspection performed roughly half an hour before and after working hoursregular full maintenance and inspection, including periodic overhaulreplacement or repair of component parts within a working periodbased on the expected duties and conditions.
As this system is very comprehensive it can only be instituted by firms with adequate workshops, experienced staff and the ability to substitute other plant whilst a full overhaul is being undertaken.current and anticipated workloadthe role of the Bill of Quantities in the estimating process The Estimating Process with Bills of QuantitiesEstimating is the process by which the cost of carrying out a quantified work activity can be established using historical data, synthesis of the activity and computer generated software information.The contract Estimate produced by the Estimator in conjunction with the pre-contract Tendering team is their assessment of the cost of a contract; this has been derived from the information provided by the Client to the Architect and Quantity Surveyor and research, investigations and planning carried out by the team. This will include processes and document production which will assist the estimator to establish a cost to complete the project. They include amongst others:Risk assessmentsSite investigationResource availabilityContract programmeSub-contract availabilityThe drawings and specificationPreliminaries and individual site conditions and locationForm of Contract and requirementsPrime Costs and Provisional SumsWhen the Designer/Architect has produced the drawings for a Project these are passed to the Quantity Surveyor who will prepare the Bills of Quantities. This is a document which lists the items and describes the work that is to be done in order to construct the building.
This allows the Estimator to itemise the materials, parts and labour for each operation. The BQ will also include preliminaries, material specification, details about the form of contract, Prime Cost (PC) and Provisional Sums (PS) inclusion and other factors which will affect how the work will be carried out and the quality and allowances to be incorporated.Once the BQ has been prepared it is sent to the companies who are invited to Tender for the contract. Each company who wishes to tender will then cost each of the items in order to obtain an overall Estimate.
Before a Contractor decides to submit a Tender for a Contract they need to decide if they wish to price the contract, taking into account all relevant factors, and finally determine what profit they expect, before turning the Estimate into a Tender.Estimators need to keep up to date with the factors which will influence costs such as Plant, Materials and Labour availability.The Estimating process incorporates decisions about:equipment needssequence of operationsnumber of workers requiredphysical constraints at the siteconditions of contract Allowances must be made for wastage of materials, inclement weather, or any other factors that may increase costs.
These will need to be incorporated into the estimate. Once these factors have been considered the Estimator will produce a cost summary for the contract and include Profit and Overheads; and move the process on to the Tender Production Stage.