12 minute read
Procurement in Construction
Management Procurement Systems
Mohammed Elaida MCIOB
Advertisement
Definition
A management-oriented procurement system has existed for a considerable amount of time, but only in the late eighties that there has been a standard-form contract for this type of procurement. The increased use of this system was due to commercial clients and property developers’ aim to commence and complete their projects as early as possible. The system was introduced as a result of:
• The diversity, difficulty and standardisation of construction methods.
• The increasing importance of the sub-contractor.
• The construction projects increase in size, the requirement for stricter project duration and budget and a more integrated project management team.
In management-orientated procurement systems, the contractor is raised to the position of a consultant and special importance is placed on the integration of the management of both design and construction.
Types of Management Oriented procurement systems
1. Management Contracting:
Work packages are managed by the contractor. The latter is supported by and works hand in hand with the professional team while providing his management expertise to the design. The actual works are carried out by others. Management contracting system was the first fast delivery system to shorten the time allocated to the procurement process. The system permits the management contractor and the client’s consultant to develop a professional team dedicated to achieving the client’s objectives.
The main features of this procurement system are:
• The contractor is appointed on a professional basis as an equal member of the design team providing construction expertise.
• Reimbursement is on the basis of a lump sum or percentage fee for management services plus the prime cost of construction.
• The actual construction is carried out by works or by package contractors who are employed, coordinated and administered by the management contractor.
2. Construction Management:
The system was originated and popularised in the USA. It is, now, gaining popularity in the UK as well as in developing countries such as Malta. The client appoints a construction manager/project manager, as a professional consultant and on a fee basis, to plan, manage and coordinate the design, carry out construction site
inspections, issue site instructions and ensure the smooth buildability of the project.
The system is comparable to management contracting in terms of the project’s division into work packages. However, the fundamental difference between Construction management and management contracting is twofold. First, the absence of sub-contracting practices under the former system. Second, the construction manager is appointed much earlier than the management contractor, even before the Architect/consultant. Moreover, the construction manager acts as a professional consultant to the client, as opposed to the commercial-oriented management contractor.
3. Design and Manage:
In an effort to merge design-and-build and management systems, the client may choose this system by appointing a single organisation, a contractor or a consultant, who shall be responsible for the project's design and management by means of work packages.
While the project is carried out by works or package contractors, the reimbursement is generally fee-based or lump-sum.
Advantages:
Early involvement of the management contractor leads to problem-fee buildability, more realistic planning, better works packaging and better project team integration.
The management contractor and the architect are on the side of the client. Hence, there are no ‘them-and-us’ attitudes and hence no adversary relations.
The fast-track approach, buildability advice and better planning during the design stage, resulting in the early start of works on site, and hence early completion.
More flexibility during the construction phase.
Disadvantages:
The client cannot predict the project’s cost from the outset.
The management contractor’s obligation may not be well defined. As a result, the client may be subjected to greater risk from construction contractors.
The management contractor may exert some pressure on the architect. Hence, design quality may suffer.
Like traditional and design-and-build systems, works sub-contractors have no direct contractual relationship with the client. As a result, they may suffer late payments from the management contractor.
Apertures Materials
Fabrizio Gerada
One of the essential aspects of a building is windows and doors since they separate the tenants from the outside world, whether it is thermal characteristics or sound issues. Nowadays, windows and doors are considered part of a building, and while they are individually tested, in the end, they are regarded as an integral part of the building. They should perform in line with the other building elements in tests, such as the door blower.
A window is composed of three primary materials, which are the frame, fittings and glass. In all three categories, there are an array of products from different brands, but what's critical is the characteristics of each. In this article, we will focus on the framing material and the characteristics of each.
Materials vary from Wood, Aluminium, uPVC, Steel and Stainless Steel.
Which material to select ranges according to your needs, but wood, for example, is considered to be more elegant and gives a sense of warmth and comfort; however, it requires much maintenance, which is typically required every five years, especially in climates with high levels of ultraviolet rays exposure. On the other hand, Aluminium offers strength and attracts the attention of architects and designers because of its narrower profiles and variety of colours. Like other ferrous materials, Aluminium is available in cold and thermal break versions. The latter tend to have deeper frames as they are separated by a polyamide resin material, separating the external and internal parts and reducing the structure's conductivity.
On the other hand, uPVC materials were designed to compete with wood to eliminate the maintenance issue. Such windows are composed of an internal steel part inserted in the uPVC profile to offer stability. The future of this material is towards having a narrow profile and eliminating the internal steel parts. The reason is that since the material has a very low conductivity, many are opting for this material as a material of choice to reach higher insulation levels. On the high end of the spectrum are steel and stainless steel, including other precious such as corten and brass. Apart from offering strength and the most minimal profiles available, they are a status symbol, giving that extra edge to your property in comfort and value.
Eventually, your choice will boil down to six choices:
Sound Insulation Thermal Insulation Security Level Aesthetics Availability Price
As in any other industry, many brands design and extrude raw materials, and then there are the window manufacturers who assemble your windows. The majority of window fabricators are tied with one or two profile brands. The difficulty comes in the cheaper products, like cold profiled aluminium, where although everyone fabricates the same design, for example, Trialco, the extrusion can be done by different companies with different thicknesses and paint characteristics. By asking your window manufacturer of trust specific questions about your technical requirements or identifying your needs, one can decide which material to choose according to the six choices.
Floating Ultra High Durability Concrete Breakwater structure, Banagher Precast Concrete
Floating Ultra High Durability Concrete Wind Turbine element, Rover Maritime Group
Quality in Construction
In recent years Malta saw a shift towards commissioning a site investigation before a project actually commences. This shift was driven partially by the fact that in the recent past there were a number of accidents which involved third parties that might have easily been avoided with a proper site investigation and proper guidance by professionals that can properly interpret the investigation document and relate the findings to what there is on site.
The main purpose of a site investigation is to properly identify issues that are relevant to the site in question and to understand better the specific ground conditions that will ultimately affect the development being proposed. Thus, this investigation inherently gives a better understanding to the architect and the engineers responsible for the new construction and guide them towards the right choices that would enable safe and economic constructions. In a very broad sense, the ground investigation is understood to include not only the underlying rock or soil, but also the ground water regime or any other underlying conditions that might be relevant. A site investigation on the other hand will give a broad understanding of the construction methods used for neighbouring buildings so that decisions on the way forward on how to construct the building in question can be taken.
The need to carry out a site investigation
The characterization of the ground conditions whether it is a greenfield site or a site that has already been developed will include geotechnical, geo-environmental and structural issues. The investigation of all these will result in an economic, cost-effective design without a lot of site disruptions that may develop if these issues are not studied beforehand. The investigation should allow for a comprehensive risk assessment of the conditions of the site to be made. The risks to be identified may include risks related to health, engineering, financial and regulatory which may all arise from unforeseen ground conditions and liabilities.
The main objectives of a Site Investigation
The main objectives of a site investigation are the following:
1 To determine the suitability of the site and the surroundings to the project being proposed and to try and understand better the engineering challenges at hand.
2. To obtain all the necessary design parameters to be able to do the necessary geotechnical and structural design.
3. To understand better the potential ground and ground water conditions that would affect the construction. To also get a better understanding of how the neighbouring buildings are constructed and how this might affect the construction of the structure being proposed.
4. To understand better if there is any risk of contamination in the ground and if there is to understand what kind of contamination one is dealing with. This does not only have an environmental effect but also an effect on the kind of materials chosen for the project.
5. To understand if there are any materials present on site that can actually be used in the project itself.
6. To understand better how the proposed design affects the adjacent structures and possibly the ground water.
Data present in a Site Investigation
A site investigation is classified as the gathering of information about the proposed location of the project. The process of the site investigation can be categorized in the following areas:
1. Desk Study – This should be done every time and before any intrusive site investigation is made. During this stage research on the site is done to gain as much information as possible both from a geotechnical and a historical point of view. A desk study draws together existing information from a variety of sources to form an initial appraisal of possible ground conditions. The desk studies must consider past uses and the current status of the site. This should include the gathering of information on neighbouring structures that might be affected by the proposed development. Records of previous SI would be useful information. Other useful information may include data of services such as electricity, water, sewers, network systems etc. Records of neighbouring structures may also be included in the site investigation. Here one can thus understand better the benefits of having a centralized information library including architectural and structural details and calculations of all the developments that are constructed. In this way the data for the desk study is readily available to other engineers and architects. This would reduce the need for assumptions and thus would reduce the chance of mistakes being made.
2. Walk-over Survey – This can give a very good insight into the ground condition problems and contamination issues. Such site visits usually also give rise to contributions being made by neighbors and other residents that also have their value to help structure other investigations that in all will help get a clear picture of the site conditions. The combination of the desk study and the walk-over survey is a cost effective first stage of the investigation as it provides a strong basis for a structured and more informative further investigation by other intrusive means. In other words, it is always better to understand beforehand where it is better to do the intrusive investigation than just investigating in the blind. Like that there is more guarantee that the intrusive investigation is more meaningful.
3. Site Investigation Planning – There are two aspects to the site investigation, the geological structure and character of the site and the testing of the soil/rock both in the laboratory or in situ. When planning a site investigation, the following points should be considered. The succession of strata over the whole site should be known. If there are any questions regarding this, the site investigation should be designed in such a way to address this issue. The homogeneity of the strata of rock or soil across the site should be understood in the process and if there are any localized variations these should be found and understood well as these might have an adverse effect on the structure erected. Ideally the flow of water across the site if this is present should be understood as this might affect the general stability and integrity of the structure.
4. Ground Investigation – There are two principal ways to investigate the ground conditions – the trial pits and boreholes. There are also the geophysical techniques such as the seismic surveys that are becoming lately popular on larger projects locally. Trial pits are ideal if the information required is at a shallow depth as these provide more extensive information, then boreholes in general. These are also good to detect services. The trial pit can be done either by hand or by a hydraulic excavator. A trial pit log should be made following investigation by trial pit. This should include the orientation and size of the pit, detailed sketches of faces, depth scale, water level and water seepage if any. Weather and time of sampling should also be
