Design Economics & Cost Planning Flashcards
(53 cards)
What is the difference between an Order of Cost Estimate and a Cost Plan?
an OCE is prepared earlier on in the design process - typically between RIBA Stage 0 to 2
Level of design is more limited and so costs are usually based on £/m2 or £/ft2 or unit basis
A cost plan is produced typically at each stage from Stage 2 onwards.
As the design progresses more information can be included to eventually breakdown the estimated cost of development elementally into each component part (e.g. substructure, superstructure, services, professional fees)
What is the difference between cost and price?
The cost is the total cost of labour, plant, materials and management deployed for a specific activity
The price is the amount the purchaser or client will pay for an item or product and is made up of cost plus MC profit margin
How do you proceed if the cost plan exceeds the project budget?
I would analyse the costs to assess the source of the increase and identify whether any element of the work is abnormally high against the OCE.
When the reason for the overspend is identified I would then look to propose value engineering options to my client and design team to bring the forecast back in line with the project budget.
What is buildability?
Buildability is harnessing the contractor’s expertise and knowledge during the design stage to generate ideas for effective and efficient methods of construction.
What are the advantages of buildability?
Can result in better programming, sequencing and construction methods
A quicker, more efficient programme can be achieved
Reduced capital and life cycle costs of the building can be obtained
The quality in the finished building’s performance and maintenance characteristics can be improved
What is wall to floor ratio?
The relationship between the wall area and floor area
Used to show the efficiency of a building
The lower the ratio the cheaper the building is to construct as there is less external envelope to construct in comparison to the floor area
What is the most efficient shape?
In theory, a circular building would offer the most efficient design as there is less wall to floor ratio
In reality a circular floor plate has poor lettable floor area and is difficult to fit out, therefore a square is considered to be most efficient
How would you prepare an estimate for M&E works?
I would consult a specialist M&E surveyor to undertake the estimate
For feasibility estimates the M&E amount would be included in the m2 or functional unit rate
What is a Section 106 agreement?
S106s are agreements between local authorities and developers that are negotiated in the context of granting planning consent
What is construction to ‘shell and core’?
Shell and core is the basic structure, services and envelope of the building.
This normally includes fit out of landlord and common areas for example reception, toilets, lifts and stair cores
Base services are usually terminated at entry points to each of the lettable floor plates however life safety services infrastructure is usually provided
What is CAT A fit out?
Known as ‘developer’s fit out’
Provides generic fit out items to suit most developers, e.g. life safety elements and basic fittings such as suspended ceiling tiles, raised access floor, carpets, lighting, and power distribution to floor plates.
What is CAT B fit out?
A CAT B fit out overlays the CAT A provision with bespoke elements that are specific to the needs of the building’s user to enable the tenant to occupy and use the space.
This would typically include partitions, power distribution to floor boxes, data cabling, artwork and branding, upgrading CAT A finishes and toilet finishes
Where could you find the definitions of these? (CAT A, B, S&C)
The British Council of Offices (BCO) fit out guide.
What is BWIC?
Builders Work In Connection - is usually set as a percentage of the services cost
BWIC accounts for the MC to perform any drilling, fixing, cutting and penetrations to enable the services installation
What is an Order of Cost Estimate?
Under NRM this is described as the determination of the possible cost of a building early in design stage in relation to the employer’s fundamental requirements
This takes place prior to preparation of a full set of working drawings or bills of quantities and forms the initial build-up to the cost planning process
What is the purpose of an OCE?
To establish if a proposed building project is affordable and, if affordable, to establish a realistic cost limit.
The cost limit is the maximum expenditure that the client is prepared to spend on the proposed building project.
What is the format of a feasibility estimate or order of cost estimate?
This can be presented on a cost per m2, functional unit or elemental basis.
It may also be presented as a range, for example £750-800/m2.
This may consist of element rates for the main elements of the building for example Substructure, Frame, External Walls, Upper Floors & Roof
Any site abnormal costs or enabling works are also considered
Other inclusions are Prelims, Contingency, Inflation and location factor adjustments.
What is a functional unit?
A unit of measurement that considers the prime use of a building.
E.g. a hotel or hospital the functional unit may be presented as a cost per bed
In a retail space, the functional unit would be presented as the net lettable retail space
Where would you get your rates from for a preliminary estimate?
Previous similar projects and historical data such as previous tender submissions or contract sum analysis
Other sources may include estimating price books such as Spons, the Building Cost Information Service (BCIS) or specialist contractors.
What information do you need to be able to carry out an order of cost estimate?
Building Location
Type of building
Floor area or number of functional units
Storey height
Whether RAF or suspended ceilings are envisaged
Initial floor plans, roof plans, sections or elevations
Requirements for refurbishment to existing buildings and enabling works
Indication of specification and quality
Indicative programme, procurement and contract strategy
Budget & cashflow constraints
Site conditions, probable ground conditions
Indicative M&E design intent, availability of utility services and sustainability strategy
Details of professional fees, development costs, VAT and inflation
What is a cost plan?
The cost plan presents the estimated cost of development into an elemental or functional format.
It shows how the design team proposes to distribute the funds available on the different elements of the proposed buildng.
What is the purpose of a cost plan?
Used by the cost consultant to control the development of the design
It identifies the client’s agreed cost limit and how the money is to be allocated to the different elements of the building
When would you do a cost plan?
A formal cost plan is typically issued between RIBA Work Stage 2 - 4
At Stage 2 the concept design is made available and the cost plan may be produced at a fairly high level. The CP may be broken down into the different elements of the building based on outline specification and Architectural concept drawings.
At Stage 3 the spatial coordination of the building is undertaken, the schedule of accommodation may be adjusted and the cost plan is updated to reflect this accordingly
At Stage 4 the technical design is made available and a cost plan updated to reflect the Architect and Engineering technical designs. Specialist contractor designs may also be available to support with refinement of the project costs.
The CP at Stage 4 will typically form the basis of a pre-tender estimate to compare tender returns against, although this is no longer referenced within the RIBA Plan of Work.
What are the principal components of a Cost Plan?
Construction costs
Preliminaries
Contractor’s OH&P
Contingency
Inflation
Assumptions
Exclusions
Area Schedule
List of drawings and specs for basis
