Construction economics of sustainability Docent, Dr Arto Saari Helsinki University of Technology Laboratory of Construction Economics and Management Joint

Construction economics of sustainability

Docent, Dr Arto SaariHelsinki University of Technology

Laboratory of Construction Economics and Management

Joint Seminar CEEC AEEBS SCS

13th April 2007 Dublin

Arto Saari, 13 April 2007 2

Construction projectsin Finland

Main concern construction costs Good solutions from the viewpoint life cycle costs and

ecology? No has not been clear rules and procedures Next will be presented results some studies

conducted at Helsinki University of Technology


Flexible room program with room requirements. Divisibility to different users. Permanent and special spaces.

Proposals of base building and infill. Overall design of permanent base building. Specified border between base building and infill. Construction documentation of urgent design packages.

Pushed design packages according to division to base building and infill. Pulled design documents for procurement. Pulled detailed construction documentation for execution.

Flexible Programming (Briefing)

Overall designDesign for procurement

and construction

FLEXIBUILD

Saari, A., Kruus, M., Hämäläinen, A, Kiiras, J., 2007. Flexibuild – a systematic flexibility management procedure for building projects, Facilities, 25 (3/4), 104-114.

Saari, A., Kruus, M., Hämäläinen, A, Kiiras, J., 2006. Flexibuild – A systematic flexibility management procedure for building projects. CIB W70 Trondheim international symposium, Changing user demands on buildings – Needs for lifecycle planning and management, 12-14 June 2006, Tore I. Haugen, Anita Moum, Jan Bröhner (eds.), Trondheim, pp. 463-472.


FLEXIBILE PROGRAMMING

Buildings are not programmed for a single known use but for a selected range of variation for users’ requirements


FLEXIBLE ROOM PROGRAM AND BUDGETBiomedicum 2U -project, Helsinki, Finland

Space Room Floor area Air ventilationsize

Minimum Maximum

program program

m2 m2 dm3/s/m2 dm3/s/m2

Modifiable spases:Laboratories 50 … 0 … 3500 3,0 3,0Offices 8 … 50 1300 … 4800 2,0 3,0Meeting rooms 15…30 0 … 150 4,0 4,0Rest rooms 8 … 10 80 … 100 1,0 1,0WC 5 100 … 120 5,0 5,0Total 5100Special spaces:Instrument sterilisation 40 40 4,0 4,0Restaurant 150 150 6,0 6,0Catering kichen 30 30 15,0 15,0

Permanent spaces:

Corridors and stairways 50 1780 2,0 2,0Tecnical rooms 60 420 0,5 0,5Total 2850

m3/s m3/s

TOTAL: 8280 17,2 22,0Cross-floor area 9465

Made retrospectively by Arto Saari Helsinki University of Technology E-mail: [email protected]

10 June 2006


Greenhouse gases caused by a typical new Finnish apartment building during 50 years.Source: A. Saari, Environmental impacts of residential buildings, Rakennustieto Oy, 2000 (Finnish language), available in web: http://www.rts.fi/ekotieto.hml

Phase KgCO2-eq per cross-floor-m2

%

Construction 220 6.3

Energy consumption in use phase 3200 92.1

Maintenance 47 1.4

Demolition 7 0.2


Energy management in briefing and design phase

Under Nordic conditions, the most effective way of having an impact on the greenhouse gases given off by building during its life cycle is to see that the energy consumption of building during use is reasonable.


Project control procedure

1 Target setting in project planning phase• for construction costs• for energy consumption (in use phase)

2 Verifying the designs in design phase• construction costs• heating energy consumption (in use phase)• specific LCC-LCA analyses

3 Requirements concerning implementations


Case project 1: VVO/ASO/Viikki, Helsinki

Jan. 2006

Unit Target Designs Difference %

Apartments fl-m2 5046 5046 0

Gross-floor area gross-fl-m2 6520 6809 +4

Construction costs EUR/fl-m2 1945 2065 +6

Heating energy kWh/fl-m2/a 184 172-232 -7…+26

Average ventilation air-m3/s 2.3 2.2-5.3 -5…+126

*) Tenants can adjust the ventilation of their dwellings

*)

*)

Analysis:

Buildings are larger than targeted

Construction costs exceed

Heating energy consumption exceed


Case project 1: VVO/ASO/Viikki, Helsinki

Jan. 2006

Unit Target Designs Difference %

Apartments fl-m2 5046 5046 0

Gross-floor area gross-fl-m2 6520 6809 +4

Construction costs EUR/fl-m2 1945 2065 +6

Heating energy kWh/fl-m2/a 184 172-232 -7…+26

Average ventilation air-m3/s 2.3 2.2-5.3 -5…+126

*) Tenants can adjust the ventilation of their dwellings

*)

*)

Analysis:

Ratio gr-m2/ap-m2 is poor

The bay depht of the building is low

Area of balconies is high


Case project 2:Physics Department University of Helsinki

An examle of the energy management in briefing and design phase of a construction project


Case project 2:

A target consumption calculationin briefing phase

Space Net Use Dimensioning of air ventilation Average Heating Electrical Cleaning Annualarea time m3/ Full Half ventila- energy energy maintenancesqm m2/h h/wk m3/h h/wk m3/h tion kWh/sqm/a kWh/sqm/a h/sqm/a cost category

h/wk m3/h o/oo /NB Categ.Ai vi t1i Ai * vi t2i 0.5Ai*vi

Offife room 1341 40 5,8 40 7778 1852 116 55 1,11 3,5 115Meeting room 60 40 14,4 40 864 206 154 73 0,82 4 113Storage 75 40 1,3 40 98 23 97 20 0,14 3 89Laboratory 125 40 10,8 40 1350 321 163 56 0,87 3,5 133Laboratory 75 40 10,8 40 810 193 163 56 0,87 3,5 133Laboratory 500 50 10,8 50 5400 1607 179 59 0,87 3,5 133Laboratory 445 40 16 40 7120 1695 193 62 0,87 3,5 133Storage 40 40 1,3 40 52 12 97 20 0,14 3,5 59Workshop 45 40 5,4 40 243 58 244 53 2,61 4,5 119Workshop for service man 15 40 3,6 40 54 13 105 44 0,68 3,5 101Laboratory 170 40 10,8 40 1836 437 163 56 0,87 3,5 133Laboratory 230 40 16 40 3680 876 193 62 0,87 3,5 133Offife room 775 40 5,8 40 4495 1070 116 55 1,11 3,5 115Storage 70 40 1,3 40 91 22 97 20 0,14 3 89Offife room 67 40 5,8 40 389 93 116 55 1,11 3,5 115Storage 10 40 1,3 40 13 3 97 20 0,14 3,5 99Laboratory 15 40 10,8 40 162 39 163 56 0,87 3,5 133Laboratory 90 40 16 40 1440 343 193 62 0,87 3,5 133Cold room 168 168 36 168 180 180 62 1668 0,29 6,5 207

132 45Total


Case project 2:

A target vs. designs

Estimated heating energy consuption:kWh/gr.fl sqm/yr

target 132 esimated from designs 161 difference +29 (+22%)

1. Estimated energy consumption is higher than the target set

2. The reason for the exceeding must be analyzed

3. Then the proposed designs must be developed


The researcher suggested the following measures:• The architectural designer should reduce the windowed area and look for glass-wall solutions of lower thermal transmittance.• The ventilation designer should check the dimensioning of the supply air devices and down size them, if necessary.

Results:Designs were revised based on submitted development proposals. Through the development of the design solution, the annual heating energy need was reduced from the 161 to 127 kWh/gr.fl.sqm. Developed designs can be considered acceptable.

Case project 2:

The results of cost management


An example ofeco-economical analysisIncludes:• description of alternative design solutions• calculation of life cycle costs• calculation of environmental impacts• normalization and weighting of costs and impacts• ranked alternatives

Source: Saari, A. A systematic control procedure for environmental burdens of building costruction projects. In Construction Economics and Organization, 2nd Nordic Conference, Göteborg 24-25 April 2001, pp. 107-115.


Comparison of facade lattice material:

Alternative 1: galvanized steel

Alternative 2: aluminium

An example of eco-economical analysis


Time horizon 50 years Selected interest rate 4%

Repacement cycles:• steel lattice tree times per 50 years• aluminium lattice once per 50 years



Life cycle phase Alternative 1Galvanized

SteelFIM

Alternative 2Aluminium

FIM

Difference

FIMConstruction 3 700 000 7 500 000 -3 800 000Maintenance 5 300 000 3 000 000 +2 300 000Building operating 0 0 0Removal 84 000 84 000 0Total 9 100 000 11 000 000 -1 900 000

Sensitivity analysis:

If interest rate is 1% or less, or if replacement cycle of steel lattice is four times, then LCC of aluminimum lattice become lower.




The factors influencing the value:weight

Life-cycle costs 50 % Use of non-renewable materials 5 % Climatic warming (CO2 equiv.) 25 %

Acidification (SO2 equiv.) 10 %

Oxidants (ethene equiv.) 10 %

The above weights serve as examples



Alternative Life cycle costs M FIM

Nor- mal- ized

Non-renew.

material tons

Nor- mal- ized

CO2 Equiv. kg

Nor- mal- ized

SO2

Equiv. kg

Nor- mal- ized

Ethene kg

Nor- mal- ized

Weighted normalized

value

Rating

Weight 50 5 25 10 10Standard one-family house, 121 fl.sqm 1.6 1.00 400 1.00 360 000 1.00 2 400 1.00 53 1.00 1.00

Galvanized steel lattice, 5121 sqm 9.1 5.69 610 1.53 1 000 000 2.78 1 700 0.71 200 3.77 4.06 2.Aluminuum lattice, 5121 sqm 10.6 6.63 100 0.25 260 000 0.72 1 900 0.79 13 0.25 3.61 1.




Alternative Life cycle costs M FIM

Nor- mal- ized

Non-renew.

material tons

Nor- mal- ized

CO2 Equiv. kg

Nor- mal- ized

SO2

Equiv. kg

Nor- mal- ized

Ethene kg

Nor- mal- ized

Weighted normalized

value

Rating

Weight 50 5 25 10 10Standard one-family house, 121 fl.sqm 1.6 1.00 400 1.00 360 000 1.00 2 400 1.00 53 1.00 1.00

Galvanized steel lattice, 5121 sqm 9.1 5.69 610 1.53 1 000 000 2.78 1 700 0.71 200 3.77 4.06 2.Aluminuum lattice, 5121 sqm 10.6 6.63 100 0.25 260 000 0.72 1 900 0.79 13 0.25 3.61 1.

reference level weights

rating of alternatives




The aim of this study was to examine changes in the overall costs of an office when the efficiency of space use is increased.

The variable in the examination was a space index, calculated as the floor area per employee.

The quality of indoor climate was also a variable in the analysis.

An example of

Socio-economic analysis

Source: Arto Saari, Topi Tissari, Esko Valkama and Olli Seppänen (2006). The effect of a redesigned floor plan, occupant density and the quality of indoor climate on the cost of space, productivity and sick leave in an office building–A case study, Building and Environment, Volume 41 (12), 1961-1972.


Cell office (2)

Open plan office (3)

Initial plan (1)

Saari, Tissari, Valkama, Seppänen 2006

Arto Saari, 13 April 2007 24Seppänen, Fisk, Faulkner 2003 Saari, Tissari, Valkama, Seppänen 2006

An example of socio-economic analysis

Models


Arto Saari, Topi Tissari, Esko Valkama and Olli Seppänen (2006). The effect of a redesigned floor plan, occupant density and the quality of indoor climate on the cost of space, productivity and sick leave in an office building–A case study, Building and Environment, Volume 41 (12), 1961-1972.


An example of socio-economic analysis

Results

Source: Arto Saari, Topi Tissari, Esko Valkama and Olli Seppänen (2006). The effect of a redesigned floor plan, occupant density and the quality of indoor climate on the cost of space, productivity and sick leave in an office building–A case study, Building and Environment, Volume 41 (12), 1961-1972.

The overall cost analysis of a given case building showed that when space use is boosted significantly, measures must be taken to guarantee a sufficient quality of indoor climate.

The study indicates that investment in the quality of indoor climate is cost effective when the economic effect of indoor climate to health and productivity are taken into account in addition to the costs of investment, operation and maintenance. Insufficient ventilation without mechanical cooling may cause a substantial loss of productivity. The importance of good ventilation and air-conditioning increases with a more efficient use of space especially in conjunction with high value of work.


Contact:

Dr Arto Saari

Helsinki University of Technology

Laboratory of Construction Economics

Box 2100

02015 TKK

Finland

Tel. +358 9 4511

E-mail: [email protected]

Documents

Construction economics of sustainability Docent, Dr Arto Saari Helsinki University of Technology Laboratory of Construction Economics and Management Joint