RIBA Work Stages
Preparation Appraisal
Design Brief
Design Concept
Design Development
Technical Design
Pre-construction Product Information
Tender Documentation
Tender Action
Construction Mobilisation
Construction to Practical Completion
Use Post Practical Completion
A - Appraisal
This is where client’s requests and aims are recognised and explained. It is important that issues such the need for the new building is fully investigated. This includes the lifespan of the building, the budget and established needs are addressed.
The feasibility of the project it is considered with alternative options judged and described to the client.
B - Design brief
The Design Brief includes the requests and goals of the client. A procurement method is identified with procedures, the consultants and organisational structure being decided. The design team is assembled and a role for each person is determined.
C – Concept
The Design Concept will be prepared, including outlines for the building services system and the structural requirements Outline specifications and preliminary costs will be looked into.
D - Design & development
Design concept will be developed with aspects of health and safety being considered. Stages C and D will evolve into the Project Brief, this needs to be finalised then an application can be made for planning permission.
E - Technical design
This is where technical detail is developed in an approved design as to which materials and workmanship standards are chosen. This stage does not need to be complete but it needs to be adequate to ensure initial elements can commence and information on construction safety and statutory standards are required.
F - Production information
The planning application is submitted to the Local Authority for approval. Information is detailed in preparation for construction. The proposals are finalised and concentrated into technical specifications and instructions, therefore sufficiently allowing pricing for construction of the project.
G - Tender documentation
All tender documentation (the form of tender, tender drawings, bill of quantities, and the letter of invitation) are prepared. Contractors can be sought once this information is set out and then tenders for the project can be returned.
H - Tender action
Contractors and specialists are acknowledged and assessed with recommendations made to the client normally based on the best value for money.
J - Mobilisation
A contractor can be appointed with a detailed contract and deadline being implemented based on all the information provided
K – Construction to practical completion
The monitoring and management of the site will ensure that the project is being run in line with contract and statutory requirements. This is maintained from the beginning to the practical completion of the project.
L – Post practical completion
Once the final inspections have been carried out, this can ensure that the building is compliant with the contract and statuary requirements.
The client can then take possession of the building and a review of the project performance is carried out.
Question 2
CJS Associates Ltd
Urban Office Project
A report on the site set up and cost issues
For:
Ewan Craig Ltd
12 March 2013
By:
Calum Stringer
CJS Associates Ltd
Contents
1 Introduction
2 Factors that affect site set up and costing
3 Conclusions
4 Recommendations
1. Introduction
This report aims to analyse the reasons behind delays in site set up and why costs may have increased at the newly proposed Office building.
The site is situated in a city centre commercial development and the proposed structure for is a two storey office building with associated car parking.
The Construction site is a confined urban site with difficult access and limited storage facilities, the soil is non-cohesive with relatively poor load-bearing capacity covers the site to a depth of 2m, with stable load-bearing strata below this. The groundwater table is approximately 1.8m to 2m below ground level.
2. Factors that affect site set up and costing
With the site being based in an urban location, the construction progress will change with different process along the design phase, there are many factors that will affect the initial set up of the site
Site Clearance and Demolition
Site clearance and demolition is required to remove all buildings from the site in anticipation of the new building. It also includes ground remediation where soil has been contaminated radiological or other contaminated. Decommissioning of the site is the process which relates to decontaminating and the clean-up of contaminated land.
Demolition Notices have been required by the he Council’s Building Control service to be notified of all demolitions which require certain conditions to be included
The setting up of the site for the contractor will include:
• Additional accommodation
• Location to store plant and machinery
• Parking facilities
• Storage provisions for materials
• Temporary installation of services
• Facilities for loading and unloading of goods
• Preparations for concrete to be installed.
• Sanitary Facilities.
Key issues
Before work starts written procedures have to be prepared for demolition and carried out so that any danger is minimised.
Precautions need to be taken because of work near energy distribution installations and electrical power cables, and where work takes place near water.
Measures have been introduced in order to prevent machinery rolling or dropping into pits and trenches or over running onto embankments.
Foreseeable emergencies have been planned for and the site is maintained in order to minimise these risks.
Safe access has been provided to the site and sufficient space provided for the activities that are to be carried out.
Fire prevention, detection and fire fighting equipment have been required to be installed prior to works starting on site.
An adequate supply of fresh air, adequate temperature and sufficient lighting must be provided in workplaces.
Excavation work
A sufficient and suitable risk assessment has been required to avoid an excavation collapse. Considerations of the following issues have been looked into:
• An initial ground survey
• Related risks from the environment (local river, high water table)
• Excavation support and edge protection requirements
• Protection and safety of adjacent structures
• Safe positioning of spoil heaps and vehicles
• Access to the site
• Any emergency procedures
With the standard of soil currently on the site it is imperative that suitable foundations are laid. Due to the nature of soil testing it has been required to ensure the type of foundation that is laid is sufficient enough to handle the load of the building and minimise potential problems.
Excavation trenches must be properly supported and measures must be taken to prevent collapse of nearby buildings or materials falling into the excavations. Equipment must not be placed too close to an excavation such that there is a possibility of collapse.
Subsurface investigations have been required to fully identify:
• The subsoil conditions by producing test borings, which were provided by a soil engineer. Numerous borings were made due to the site conditions.
• The borings need to extend into firm Strata (bypass unsuitable soil) to extend into more acceptable soil.
• The borings are required to indicate the soil depth, soil classification, the moisture content and where ground water level is.
The Soil report has recommendations based upon the testing of materials obtained from onsite borings and to include the bearing capacity of soil, recommendations for the foundation design, the soils compaction and its permeability.
Due to the nature of the subsoil the cost of foundation will require deeper foundation to enable the land to take the load of the new structure.
Due to the high level of the water table works are required to improve drainage to the site and minimise the potential issues this can cause.
Site Access
Due to the location of the site, haulage and access road have been required to ensure the success of the project and completion in a timely manner.
There have been co-operation requirements with the local councils, businesses, residents, and organisations to aid the planning of the works. The site has to maintain practice standards and is subject to stringent controls to which the local council can ensure is imposed upon the site.
These can involve restrictions to site movement and access during certain times of the day to minimise disruption to local facilities and businesses.
Safety and Welfare
The contractor is responsible to ensure the high levels of site safety are adhered to. This includes direct employees and subcontractors as well as any potential issues with the general public.
Public responsibilities
The perimeter of the site must be adequately fenced to minimise trespass and no unauthorised access, this ensures site traffic is separated from pedestrian routes. These routes have to be well maintained and signed.
With the impact of traffic, dust, noise and other disturbance on local organisation and neighbours, it has been necessary to arrange some works for evenings and weekends, which has led to increased labours costs.
There has been work needed to enable changes to site access to separate new building works from the present facility.
It has been a requirement to maintain current services for local residents and business due to the effect of periods of loss of power or water being detrimental and to minimise disruption.
The construction site will pose a problem for uncontrolled dust for areas surrounding the site. The site must have effective control measures in place as failure to adhere to dust control requirements often causes issues for construction sites until dust is under reasonable control.
Material Management
The cost of security is required due to the nature of the need to stockpile construction material around the site. This becomes a potential target for thieves. By ensuring sufficient security is in place and that materials are stored in a correct and secure area then this can minimise theft and loss of materials and money.
3. Conclusions
• The current soil structure requires significant works to ensure the structure can be built onto the site and to minimise issues with the water table.
• The Urban location poses issues for access and deliveries of materials with works required to the current site
• Works are required to maintain on site safety and public safety.
4. Recommendations
By introducing good working practices on site this can help to minimise issues with local residents and potential delays in the project.
Ensuring the correct soil and ground set up is crucial to avoid issues with the building of the development.
Question 3
When comparing Concrete and Steel there are various reasons why it would be a preferred material for the structure of an office block.
For urban projects, the benefits of speed of construction and minimised on-site storage of materials are that of steel framed systems however they do require a higher level of pre-fabrication.
The steel framed buildings are swift to be constructed, are of high quality, adaptable and flexible in application, and are more energy efficient than concrete. Steel composite construction have the recognised benefits of long spans, construction speed, the ease of integration of services, improved quality and the reduced environmentally friendly impact.
With steel construction using pre-fabricated components installation can be rapid. With these shorter construction times this will lead to saving in preliminary costs, a reduction in interest charges on finance and a quicker return on investment. In more urban projects the need to reduce disruption to local roads and building is more achievable.
For open plan offices the space can be arranged easily with the use of long spans, and the flexibility and adaptability of this means that different layouts and variation in layout can be implemented throughout the height of the structure.
Comparison of advantages and disadvantages between Steel and pre-cast concrete framed structures for the construction of the office building
Standard steel sections and connectors are relatively expensive and light weight however limited in selection. With concrete framed buildings the basic materials are comparatively cheap however more mechanical connectors are used.
Design and manufacture of Steel work fabrication has a high level of automation, as the components are prefabricated in workshops this consumes both time and financial investment, from design through to fabrication . Pre-cast concrete framework also requires off-site manufacturing capability. Due to the nature of this it can be seen that it has more process because of the use of moulds and for the setting of the concrete.
Times for delivery for materials can be extended during busy period in the construction industry and time must be given for fabrication of the steel. With steelwork a range of structures can be assembled into designs and alterations can be achieved if required and further extension to an existing building is possible.
With concrete framework numerous shapes can be manufactured, however the most efficient use of this form is by standard sizes and repetition. The size will determine the limitations of the prefabrication due to modes through modes of transportation this may then require on site work to assemble these sections into a larger frame. Due to Precast concrete being heavier, the load capacity will be based on the maximum size
As long as management maintain control of the parts and connectors then assembly work is straight forward but plant machinery maybe, however erection is generally swift. With concrete frames the assembly is generally similar to steel however the plant machinery requirement is greater and more susceptible to damage. Quality control in fabrication ensures the accuracy is greater than concrete however precast concrete units will have a generally higher level of finish compared to steel.
Fire resistance in precast units is greater than steel due to the requirement of a protective finish or cladding to reach fire safety standards. Where steelwork is exposed it can rust without protection and steel has a reasonable resistance to minor impacts. Structural steelwork has a high strength to weight ratio, so is effective for long spans.
However, steel frames transmit vibration well, which can cause problems in some buildings, such as laboratories containing sensitive apparatus. The material is dimensionally stable and does not undergo long-term deformation or shrinkage. Steel can be recycled and is more efficient in terms of pollution then the production of precast concrete.
Bibliography
CEM (2007) ‘Design Issues’, Paper 1608. Reading; The College of Estate Management.
CEM (2009) ‘Substructure’, Paper 8006. Reading; The College of Estate Management.
CEM (2007) ‘Framed structures –typical details’, Paper 8008. Reading; The College of Estate Management.
CEM (2007) ‘Framed Structures’, Paper 8009. Reading; The College of Estate Management.
http://www.ehow.co.uk/list_6951536_advantages-steel-frame-buildings.html (Last accessed 14 Mar 2013).