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3.14.1 Life cycle repairs / replacement (renewals) works can be estimated from either capital cost plans,

during the construction procurement, or from asset specific maintenance data (i.e. asset maintenance registers and condition / remaining life surveys). The level of information available and resultant methodology to estimate the life cycle renewals cost is different for each scenario, however both should be prepared in accordance with the preparation rules defined in clause 1.9.

Life cycle major repairs /replacement (renewal) works - during the construction procurement;

3.14.2 The Life cycle repairs and replacement costs, during the construction procurement process, can

be derived from the capital building works elemental cost plan. The life cycle replacement costs are normally built-up from first principles using the following information contained in a typical

elemental construction cost plan, namely:

o Description of the elements, sub-elements and components

o Quantity and unit of measurement of the elements, sub-elements and components o Capital cost rate of the elements, sub-elements and components

3.14.3 To generate the renewal forecast cost per replacement event the capital building works unit cost

rates needs to be adjusted to reflect the renewal costs for each of the items, by applying agreeing the replacement cycles (i.e. reference service life); agreeing an uplift factor (%) and then quantity of replacement (%), which can then be used to calculate a cost per replacement event. For example: Window with a capital cost of £500 each (i.e. element unit rate).

(a) Replacement cycles - Window 20 years

- Ironmongery 5 years

b) Uplift factor for renewal % - Window 15% on build costs for refit price - ironmongery 25% on build costs for refit price c) Quantity of replacement % - e.g. 80% of windows (Note: 20 year life expectancy)

Window

Cost per replacement event = a) £500 x b) +15% x c) 80% = £460 /event (for 20 year life item)

Ironmongery

Cost per replacement event = a) £500 x b) + 25% x c) 20% = £125 /event (for 5 year life item)

3.14.4. Replacement life frequencies need to be applied all to the relevant work component, quantities

and costs, in order to then generate the related life cycle replace costs over the period of analysis.

Note: Refer to item 3.15 for more detailed instructions on determining the asset life expectancy; applying uplift factors % and quantity of replacement % and replacement lifing frequencies. 3.14.5 Compiling all of the relevant replacement assets replace cost forecasts will create a first cut of the

life cycle replacement cost plan for the period of analysis. Further review and analysis of the forecast is required, using various factoring and sensitivity analysis techniques, in order to cost check and validate the results. Refer to item 3.15 for details on factoring and sensitivity analysis.

3.14.6 In option appraisal may use the life cycle replace forecasts, or cash-flows of multiple replace

forecast cost plans, in order to compare the results – with or without a base case comparator.

Life cycle repairs and replacement works - during the ‘in use’ stages (i.e. post construction)

3.14.7 Life cycle renewal cost plans during the in-use phase are fundamentally different to the method

used during construction work stages. The cost plan will be based on asset register information, as construction as built cost plan records are unlikely to be available and are generally inaccurate as the facility may have had alterations and adaptations since it was built. Before using any

existing assets maintenance register they must be verified, as it may not have been kept fully up to date. Refer to clause 3.14 to 3.17 for more detailed rules of measurement for in use cost plans

3.14.8. Should the project stakeholders require a replacement plan for a longer period of analysis beyond

the next 3 to 5 years, then typical condition surveys will normally only have short term views on identified repairs and replacement based on asset condition and remaining life assessments. Therefore the scope of the condition survey will need to be widened to include all relevant replace items (from applicable 4R and 5R list in part 3) include asset quantification for all assets in scope.

3.15 Information requirements for costing the renewal works

3.15.1 The life cycle replacement of assets and their major component parts is intrinsically linked with

the life expectancy resulting from the built environment that contains them. Hence the primary source of information and data sources is from the construction works and functional performance standards peculiar to the constructed asset and the functional usage of the built environment.

3.15.2 There are various industry sources of reference service life of components for common building

components based on testing laboratories and specific advice from manufacturers, trade associations and research organisations, particularly the Building Research Establishment. There is less information available about the general performance of materials and components in buildings in use. BCIS – Life expectancy of building components

3.15.3 Information requirements are listed in Appendix E1/ E2 – of which the minimum level required is:

o Applicable asset register in scope – i.e. the 4R & 5R renewal list (refer to tables in part 3) o Condition surveys findings – identified actions required (major repairs and replacements) o Remaining life assessments – from condition assessments or failure mode analysis o Next intervention points – frequency and next date of repair and replacements by assets o Lifing factors to be considered – to adjust extent, timing works and associated cost rates

3.15.4 This document provides an initial reference point for life expectancy information for inputs into:  Life cycle costing at the feasibility stage of a project

 Determining approximate component replacement intervals at outline design stage  Considering the life expectancy of specific designs (as part of an option study)  Value engineering workshops

 Assessing remaining life in stock condition surveys  Risk analysis of failure and life expectancy

 Analysing the causes of deterioration of building components  Benchmarking the performance of buildings and components in use

Source – BCIS: Life Expectancy of Building Components (2nd revised edition 2006)

Typical Life Expectancy Softwood Windows 0 5 10 15 20 25 30 35 0 to 5 _{6 to} 1 0 11 to 15 16 to 20 21 to 25 26 to 30 31 to 35 36 to 40 41 to 45 46 to 50 51 to 55 56 to 60 61 to 65 66 to 70 71 to 75 76 to 80 81 to 85 86 to 90 91 to 95 96 to 100 100+

Life expectancy (years)

Fr e q ue n c y Mean 36 Median 30 Mode 26 to 30 Sample 74

3.15.5. The level of reference service life planning information data needed to produce a life cycle renewal cost estimate will vary depending on the purpose, use of the LCC output, scope of costs and the stage in the project. Refer to items 3.16 and 3.17 for detailed instructions.

3.15.6 For replacement elemental costs plans the reference service lives and expectancies for the asset

components can be derived from the following industry available sources: (1) Manufacturers and Trade association

(2) Testing houses and Certification Bodies, such as Building Research Establishment (BRE) (3) Published sources – such as

BCIS Life Expectancy of Building Components 2006

CIBSE Guide M - Maintenance engineering and management 2008 HAPM, Building Life Plans - Component Life Manuals

(4) Research Organisations such as CIRIA, TRADA (5) Specialist consultants

(6) Clients practice and in house records

Note - All reference service lives should be factored in accordance with the proposed use, environment and level of maintenance for the project.

Determining the asset and component life expectancy; key factors to consider

3.15.7 In order to identify the appropriate asset/ component life expectancy the quantity surveyors/ cost

managers need to make an assessment of the expected life of an asset, or its constituent parts thereof. Note – Important to first understand the distinction regarding what is difference between ‘design life’ and ‘service life’. ISO 15686 Part 1 defines the terms as follows:

Service life;- period of time after installation during which a building or its part meets or exceeds

the functional performance requirements.

Design life; intended service life, or expected service life, or service life included by the designer.

3.15.8 In practice the term ‘lifing of assets’ when applied to a constructed asset can be defined in a

number of ways depending on the interests and objectives of the user. Lifing factors to consider: Physical life (from construction to demolition or replacement). Every asset has a predicted length

of life at the end of which a physical collapse is possible. However most assets never reach that point and are demolished or replaced beforehand, generally due to economic obsolescence. Note the physical life corresponds to the ISO 15686 part1 definition of service life.

Economic life (from construction to economic obsolescence). Economic obsolescence happens

when a further use of an asset is no longer the most economic solution among alternatives.

Functional life (from construction to the point when the asset ceases to function for its intended

purpose). An asset reaches the end of functional life when it can no longer function for the purpose for which it was intended.

Technological life (from construction to the point when the asset is technologically obsolete).

End of technologically life occurs when an asset, typically a system or component, is no longer technologically equal to or better than available alternatives

Social/legal life (from construction to the point when replacement is required for social or

regulatory reasons). An asset reaches the end of its social or legal life when requirements other than economic dictate replacement or change, e.g. health and safety or legislative issues.

Contractual / duration of interest life (for any period of time during the duration the physical life

of an asset). This period of analysis covers the length of a contract for a particular service.

Arbitrary life (length of time e.g. 25, 30, 50 years), assumed due to national practice, local best

3.15.9 Factors affecting life expectancy – BS 7543; 1992 – Guide to Durability of Buildings and Building Elements, Components and Materials (BSI 2003) states that the basic causes of deterioration in buildings are due to the action of weathering, biological infestation, stress, chemical interactions, physical interactions and normal use. The standard also states that deterioration will be accelerated by:

 Poor design/ detailing

 Inappropriate selection of material or component for intended use  Quality of material or component used

 Adverse onsite storage and handling  Poor workmanship

 Inadequate maintenance  Inappropriate use

3.15.10 These factors all result from human endeavours and therefore do not lend themselves to accurate

prediction. This is the key problem associated with determining component and material life expectancy.

3.15.11 Industry recognised sources for reference services lives, provide indicative lives only and should

be used with caution as they assume that appropriate maintenance will be undertaken. In addition to the impact of the environment as described above, it states that the hours of occupation and hours run should be taken into consideration. All factorings applied should be recorded as part of the assumptions.

3.16.12 Location factors can be applied however this needs to be with caution as the life cycle

replacement costs are derived from the construction costs, which will already have the location factor applied. Location factors for local resource to carry out the replacement works may however, differ from the factors applied by the construction provider.

3.16 Measurement rules asset-specific cost plans for repairs/

replacement works (renewals -R); generated from capital

building works cost plans

3.16.1 Formal cost plan 4 is an ‘asset-specific cost plan’, which can be used to aid the procurement and

cost management of a renewal works programme (whatever the length of programme). Because it is asset-specific, the (renewal) works required to elements, components and sub-components of the assets incorporated in the building or facility are to be measured in detail.

3.16.2 The measurement process for ‘asset-specific cost plans’ generated from a capital building works

cost plan is as follows:

(a) Determine components and sub-components of assets to be replaced during

building life:

(i) Using Calculation Template with worked example, as Template R1 (Template for costing the life cycle repairs/replacement (renewals), to record data for cost plan.

(ii) Capital building works information (columns 1 to 5 inclusive): Insert element, component and sub-component descriptions, together with the quantity, unit of measurement, unit rate and total cost in columns 1 to 5 of Template R1.

(iii) Work Item (A – column 6): For each component and/or sub-component, identify, describe and insert the replacement work required (e.g. take up existing vinyl sheet floor covering and renew with same).