Quantification & Costing Flashcards

1
Q

What is COMP6?

A
  • Code of measuring practice, 6th edition.
  • RICS published this guidance note in 2007 (updated in 2015 to apply globally).
  • Provides definitions that permit the accurate and consistent measurement of buildings and land.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Are you aware of any other measurement standards?

A

IPMS – International Property Measurement Standards drafted by the IPMSC (committee). Standards establish a consistent methodology for measuring Industrial, Office, Residential and Retail buildings globally.

SMM7 – Standard Method of Measurement (SMM) published by RICS. Provides rules for measuring building works for preparing documents such as BQs. Superseded by NRM2.

(CESMM – Civil Engineering Standard Method of Measurement published by Institution of Civil Engineers (ICE). Sets out procedure for preparing BQs for civil engineering works.)
(POMI – Principles of Measurement (International) published by RICS. Guidance for measuring building works quantities for the BQs.)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What’s the difference between COMP6 and IPMS?

A

IPMS 1 vs GEA – e.g. IPMS1 includes balconies external to main structure (but stated separately).

IPMS 2 (Office) vs GIA – e.g. IPMS2 (Office) includes balconies external to main structure (but stated separately).

IPMS 3 (Office) vs NIA – e.g. IPMS 3 (Office) includes all internal walls and columns, as well as balconies (but these are stated separately)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Define GEA

A

Code of Measuring Practice, 6th edition says:
“Gross External Area is the area of a building measured externally at each floor level.”

EXCLUDES:
- Voids over or under structural floors.

(INCLUDES:
- Perimeter wall thickness and external projections
- Internal walls & partitions
- Columns, piers, chimney breasts, stairwells, lift-wells
- Internal balconies
- Areas with headroom <1.5m.
- Pavement vaults
EXCLUDES:
- External open-sided balconies, covered ways and fire escapes
- Canopies
- Voids over or under structural, raked or stepped floors)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Define GIA

A

COMP6 says:
“Gross Internal Area is the area of a building measured to the internal face of the perimeter walls at each floor level.”

EXCLUDES:
- Voids over or under structural floors.

(INCLUDES:
- Internal walls & partitions
- Columns, piers, chimney breasts, stairwells, lift-wells
- Internal open-sided balconies, walkways, and the like
- Areas with a headroom <1.5m
- Pavement vaults
EXCLUDES:
- Perimeter wall thicknesses and external projections
- External open-sided balconies, covered ways and fire escapes
- Canopies
- Voids over or under structural, raked or stepped floors)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Define NIA

A

COMP6 says:
“Net Internal Area is the usable area within a building measured to the internal face of the perimeter walls at each floor
level.”

EXCLUDES:
- Columns
- Areas with a headroom <1.5m
- Areas rendered substantially unusable due to having a dimension between opposite faces of <0.25m
- Non-usable areas such as plant rooms, circulation areas, cores etc

(INCLUDES:
- Non-structural walls subdiving accommodation in sole occupancy
- Pavement vaults
EXCLUDES:
- Stairwells, lift-wells and permanent lift lobbies
- Internal structural walls, walls enclosing excluded areas, columns, piers, chimney breasts etc);

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is NRM2?

A

New Rules of Measurement 2 - Detailed measurement for building works

Provides guidance on:
- quantifying and describing building works when preparing BoQs, schedules of works and schedules of rates.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the structure of NRM2?

A
  1. General Introduction
    - Contextualises cost estimating in terms of RIBA Plan of work and OGC Gateway process
    - Purpose
    - Use
    - Date effective
  2. Detailed measurement of building works
    - Information on BQs including: definition, purpose, benefits and types.
  3. Rules of measurement for building works
    - Tabulated rules for the measurement and description of building works.
    - Work sections 1-41
    - Item, UoM, Level 1-3 (description information reqs), Notes (clarifies approach to quantification).
    - (Bulk of NRM2)

Appendices
- Guidance on preparing BoQs
- Templates for various pricing documents;

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the key headings for contractor preliminaries identified in NRM2?

A

Employer’s requirements:
- site records
- completion and post-completion requirements
- site accommodation

MC’s cost items:
- site records
- completion and post-completion requirements
- management and staff
- mechanical plant
- temporary services
- insurance, bonds, guarantees and warranties

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How would you measure MEP elements of a cost plan?

A
  • Identify MEP elements in the design.
  • Measure in accordance with NRM1 “4. Tabulated rules of measurement for elemental cost planning”

Group element 5: Services
- Element 5.1: Sanitary installations (for e.g.)
- Sub-element: 5.1.1 Sanitary appliances
- Component: 1 Sanitary appliances: details to be stated.
- Unit = nr
- Measurement rules for components: C1 Where components are to be enumerated, the number of components is to be stated.
- Included: WC pans and cisterns, urinals and cisterns.
- Excluded: Sanitary installations procured as part of a prefabricated building, building unit or pod.

(NRM1, p201)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How would you measure partitions for a cost plan?

A
  • Measure in accordance with NRM1 “4. Tabulated rules of measurement for elemental cost planning”

Group element 2: Superstructure
- Element 2.7: Internal walls and partitions
- Sub-element: 2.7.1 Walls and partitions
- Component: 1 Internal walls: details, including thickness (mm), to be stated
- Unit = m2
- Measurement rules for components: C1 Measure area of partition, measured on the partition centre line. No deductions for door openings, screens etc
- Included: 1 Internal walls, including full-height and low-level walls
- Excluded: 1 Internal skin of external walls

(NRM1, p169)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is BIM?

A
  • Building Information Modelling.
  • Using a shared digital representation of a building to facilitate design, construction and operation processes to form a reliable basis for decisions (ISO 19650).

(We use BIM Level 2 (Full collaboration): use of many 3D models which are federated. Level 3 (Full integration iBIM): one model in cloud environment which project team can access.)
(Government requires fully collaborative 3D BIM at Level 2 (with all project and asset information, documentation and data being electronic) as a minimum by 2016.)
(Autodesk A360, Revit, CostX, Bluebeam)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the advantages of BIM?

A
  • TIME & ACCURACY: Harvesting quantities from the model is faster and more accurate, only takes 30% of the time –> beneficial for large take-offs.
  • RISK: Providing contractors further clarity around the design and logistics - enables them to mitigate risk due to better coordination.
  • COORDINATION: use Navisworks to create federated model and then run clash detection to ensure no collisions.
  • PROCUREMENT: contractors want models, they promote interest in the project and help secure the project team.
  • TRANSPARENCY: walk through design and ensure all elements of design are captured, increases understanding of project

(BIM smooths resourcing over the RIBA stages).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the disadvantages of BIM?

A

-COST: Software licences, training staff to use it
-LEGAL: New technology, limited case law in the area
-ATTITUDES: Project team members reluctance to use BIM.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Tell me about inputting data into BIM

A

COSTX:
- Loading in drawings: DWG (1:1 – no scaling required) > PDF > JPGs/PNGs
- CostX workbooks: input item descriptions, rates, formula to calculate the total cost

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Tell me about extracting data from BIM

A

REVIT: QS agrees with client how the costs are going to be reported early in the project so that model can be set up accordingly. Most common and successful method to harvest quantities:
- ‘Tag’ elements to group them
- create schedule –> choose fields, adjust sorting, grouping, filtering –> export schedule

COSTX: measuring quantities into dimension groups using line or point tool

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the CIC BIM protocol Second edition?

A
  • Construction Industry Council Building Information Modelling protocol.
  • UK’s only standard contractual BIM protocol.
  • Legal agreement that can be incorporated into construction contracts
  • Establishes specific obligations, liabilities and limitations on the use of building information models and defines deliverables to a specific level of detail (LOD) for ‘data drops’ at key stages during the development of the project.
  • Suitable for use on all Level 2 BIM Projects.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is a CSA?

A
  • Contract Sum Analysis
  • Document prepared by contractor as part of their tender on D&B projects, PQS can define the format.
  • Breaks down contractor’s price, allowing client to analyse it and compare it to other tenders.
  • Can be used as a basis for calculating payments due to the contractor as works progress.
  • Necessary as unlikely to be BQ on a D&B project at the time the contract is entered into.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is a schedule of rates?

A
  • A list of construction activities with pre-agreed rates, which the contractor can place their quantities against.
  • Typically used when the nature of work required is known but it cannot be quantified.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is a schedule of works?

A
  • A list of the work required, allows contractor to calculate the required quantities and identify significant work and materials needed to complete the works (risk of accuracy on the quantities lies with contractor)
  • Typically used on smaller projects or for alteration work.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is a bill of quantities (BoQ)?

A

NRM2 says:
- A list of items that gives detailed descriptions and firm quantities of the contract works.
- Primarily used for tendering.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

At which RIBA stage are BoQs prepared?

A

RIBA Plan of Work Overview 2020 says:
- Typically RIBA Stage 4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

When/why would you use a BoQ instead of a cost plan?

A

BQs:
- quicker to prepare than cost plans
- typically used for tendering

  • good for competitive tendering, saves contractors time
  • good for post-contract cost control e.g. valuing variations
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Why would you use a BoQ instead of a schedule of work?

A
  • BoQ breaks the work sections down into more detail than a schedule of work
  • BoQ contains quantities for specific work items, unlike a schedule of works
  • BoQ simplifies tender analysis because contractors price the same items and quantities (rather than taking-off quantities themselves)
25
Q

What are the key advantages of using a BoQ?

A
  • Very detailed and comprehensive
  • Simplifies tender analysis - all tenderers price the same items and quantities
  • Ideal for pre and post-contract cost control (e.g. managing variations, project expenditure and cash flow)
  • Effective for interim payments and preparing the final account.
26
Q

What are the key disadvantages of using a BoQ?

A
  • Expensive and time consuming to produce
  • Potential for errors when measuring the project
27
Q

What are the two types of BoQ?

A

Firm BoQ:
- Provides a lump sum price for a fully designed project.
- If there were no design changes, it’d provide a price at tender stage equating to the final cost.

Approximate BoQ:
- Quantities are subject to remeasurement on completion by QS
- Used when there is insufficient detail to prepare a firm BQ or client decides time and cost of producing one isn’t warranted.

28
Q

When would a BoQ with approximate quantities be used?

A
  • Insufficient design information to produce a firm BoQ
  • Client believes time and money to produce one isn’t warranted
  • Suitable for a remeasurement form of contract as quantities are approximate
29
Q

What is a provisional sum?

A

An allowance or estimate included in the contract price for:
- a specific element of the works that isn’t yet defined in enough detail to allow an accurate determination of its cost at the time the contract is entered; and/or
- work that the client may or may not wish to be carried out.

30
Q

How are provisional sums expended?

A
  • The CA (JCT contracts) should issue an instruction for its expenditure.
  • Where a contract includes a provisional sum, the final amount payable will be adjusted (provisional sum is omitted and replaced with the actual cost of the work).
31
Q

How are provisional sums dealt with in the final account?

A
  • By the time the project reaches final account stage, the CA will have issued instructions to expend all provisional sums.
  • The instruction will show an add and omit (add actual costs and omit the provisional sum), the instructions are then accounted for in this way.
32
Q

How does the NEC contract incorporate provisional sums?

A
  • Unamended NEC contracts do not provide for the use of provisional sums.
  • NEC approach: if the scope of works is so unclear that a price cannot be provided with a level of certainty, the item should be excluded until it can be properly defined.
33
Q

Name the two types of provisional sum and explain the difference between them

A

Defined:
- Defined in sufficient detail: [1] nature and construction of the work, [2] how and where the work is fixed to building, [3] quantities known, [4] any specific limitations identified.
- Contractor expected to allow for them in their price and programme.

Undefined:
- Not enough information.
- Contractor not expected to allow for them in their price and programme, client takes risk for the works.
- Therefore, the contractor may be entitled to an EoT and/or additional payments when the actual works are undertaken (unlike defined provisional sum).

34
Q

Would the contractor be entitled to claim additional preliminaries and/or an extension of time when expending a defined provisional sum?

A

No. Since the provisional sum is defined, the contractor should have allowed for it in their price and programme.

35
Q

What are prime cost sums (PC sum)?

A
  • A SUPPLY-ONLY rate for materials, where the quality of those materials is unknown.
  • They exclude all costs associated with installation, fees, preliminaries and OH&P.
  • e.g. supply-only ceramic wall tiles at £50/m2
36
Q

What is the difference between prime cost sums and defined provisional sums?

A
  • Prime cost only covers the cost of supply, it doesn’t include the cost of any work relating to it (such as installation)
  • However, defined provisional sums include allowances for supplying the item and all related work to be performed by the contractor.
37
Q

How would you analyse a tender?

A
  • Analysis should follow basis of the stated method of selection which depends on the procurement route.
  • Clear and concise pricing schedules makes it easier to compare contractor pricing

General considerations:
- Measured Works Pricing - have they all priced the same scope of works?
- Preliminaries Pricing - have they all provided a suitable level to deliver the works?
- Common Contract Basis - is their price and therefore level of risk reflective of the proposed contract terms?

Prelims:
- Under 2 stage procurement, ensure contractor is not buying things in subcontractor packages that they already bought in their first stage prelims.
- Helpful to use:
- Standard preliminaries pricing schedule
- Preliminaries allocation matrix - what’s included in first stage vs second stage?

OH&P:
- Similar contractors on similar projects should have similar levels of OH&P

38
Q

What if the contractor makes an error in their tender submission?

A
  • The method for correcting errors be it arithmetical or factual should be stated in the tender documentation.
  • alinea follows JCT’s Tendering Practice Note 2017, which provides 2 options:
    • ALTERNATIVE 1 - Standby or Withdraw: contractor can standby their error or withdraw.
    • ALTERNATIVE 2 - Correct or Withdraw: Contractor can correct their error or withdraw.
39
Q

What is a tender recommendation report?

A

A document prepared by the cost consultant which recommends a contractor to the client. It should also include input from the design team. A good tender report summarises:
- Process followed to seek a bid
- Who bid and under what time period
- Information given out
- Method of analysis
- Recommendation - can be done through a scoring system, but should always be tagged back to the initial criteria.

40
Q

What is an Interim Payment Application?

A
  • A document prepared by the contractor containing their progress against each of the work elements.
  • It revalues the whole work, not just the work done since the last valuation.
  • A precursor to the issue of an interim payment certificate.

(- Basis of contractor’s interim valuation (application for payment) varies depending on type of contract used);

41
Q

What is an interim valuation?

A
  • Payment for works completed at a certain stage of the project at regular intervals, rather than a lump sum at completion.
  • Used on larger projects to ease contractor’s cash flow, on the premise that project finance is cheaper for client than for individual contractors (unrealistic to expect contractor to finance project)
42
Q

What are the main elements of an interim valuation?

A
  • Measured works to date
  • Materials on/off-site
  • Preliminaries
  • Variations
  • Retention
  • Payments on account
  • Extension of time (JCT)
  • Loss and expense (JCT)

(adjustment of prime cost sums, provisional sums (JCT));

43
Q

What are the key considerations of an interim valuation?

A

What the contract says about:
- Timeline (notice to withhold etc)
- Retention
- Materials
- Variations
- Who’s responsible
- Valuations and interim certificates

My approach to valuations/setting it up right - easier to value works with items split e.g. floor types

Common QS mistakes: using wrong previously cert value, no certificates

44
Q

How would you assess the interim valuation?

A
  • Review the contractor’s application – identify any movement in the month
  • Walk around site with contractor: check work completed, materials on-site
  • Carry out my assessment - apply appropriate %s
  • Email assessment to contractor for their comments, adjust where appropriate
  • Create a recommendation letter based on my assessment
  • Email recommendation to the CA who will issue the payment certificate

(Liaise with the clerk of works (JCT), value preliminaries, agree variations, check materials off-site)

45
Q

How are works valued?

A

Contractually:
- Stage payments: valuations of work upon reaching an agreed construction milestone.
- Interim payments: valuations of work in daily, weekly, monthly or yearly periods depending upon what’s been agreed. Can be based on a BoQ, Pricing Schedule or Activity Schedule.

Calculations can be based on:
- Activity Schedule: assessed in terms of % achieved or completion of activity.
- Milestones reached on a pre-agreed programme
- Measurement against a BoQ/CSA
- Stage payments against calendar date

46
Q

What are the implications of over or under valuing the works?

A
  • Undervaluing the works creates unreasonable financial problems for the contractor
  • Overvaluing the works puts the employer at risk of paying sums in exchange for no benefit

(An interim valuation must be a realistic assessment).

47
Q

What would you do if the contractor claims for paint in their 1st interim valuation?

A
  • Assuming the project is new build, the contractor is likely front-loading.
  • I would assess if they had done any painting during the site visit and adjust the valuation accordingly.
48
Q

What are the key things you should consider prior to valuing materials off-site?

A

Subject to contract requirements:

  • Request a vesting certificate
  • Check insurance is in place until the materials arrive on site
  • Request evidence that the materials are clearly marked for the project and are set apart from other materials
  • Check material off-site bond has been provided
49
Q

What needs to be in place to make payment for materials on-site?

A

Materials should:
- be adequately protected
- be covered by the works insurance
- arrive on-site within a reasonable period before they’re actually needed e.g. delivering doors on the first week of a new building project probably isn’t appropriate

50
Q

What is a vesting certificate?

A

A document evidencing that ownership of materials will transfer from one party to another on payment

51
Q

What does the term ‘payment on account’ mean?

A
  • A payment for an item of work (or materials) for which no instruction has been issued but is anticipated.
  • Used by the QS for any item in a valuation that cannot be agreed under the contract rules, but both sides agree that some payment is due.
52
Q

Can you explain what is meant by the term ‘daywork’?

A
  • Contractor is paid for their work based on the materials, plant, labour used plus OH&P.
  • Used when work cannot be priced in the normal way.
53
Q

What is a variation?

A

An alteration to the scope of work originally specified in the contract through addition, omission or substitution of the works, or changing the way in which the works are carried out.

54
Q

What information is typically shown on a payment certificate?

A
  • Certificate date
  • Contract date
  • Contractor, employer and employer’s agent details
  • Site address and project number
  • Contract Sum
  • Gross Value
  • Less retention
  • Less works not in accordance with contract
  • Net valuation
  • Less cumulative value of previous payments
  • Amount due (excludes VAT)
  • Employer’s agent signature
55
Q

What happens if the employer fails to pay the amount due (on the payment certificate) on or before the final date for payment?

A
  • Employer will be liable for interest on the amount due (subject to contract conditions)
  • Contractor may exercise their right to suspend part or all of the works.
56
Q

What is a ‘pay less notice’?

A

Gives the paying party the right to withhold all or part of the notified sum.

57
Q

What are the employer’s obligations if they wish to withhold the notified sum, but fail to issue a pay less notice?

A

If the paying party doesn’t serve a valid pay less notice timeously, they are obliged to pay the notified sum without deduction, regardless of whether they have a valid challenge to the sum.

58
Q

Can you explain the payment timeline for the JCT Design & Build 2016 contract?

A

NB: Interim Payment Application (or Payment Notice) = contractor’s assessment of money employer owes them.

(Day 00) Interim Valuation Date - Contractor required to make an Interim Payment Application before this date.

(Day 07) Due Date - Date up to which the works are valued.

(Day 12) Payment Notice - Employer issues contractor a ‘Payment Notice’, stating the sum they consider to be due to the contractor at the due date, otherwise application becomes the Interim Payment Application.

(Day 16) Payless Notice - If the employer will pay less than the sum in the Interim Payment Application, they must notify the contractor.

(Day 21) Final Date for Payment - Employer must pay contractor on or before this date.