Design and Detailing for
Toxic Chemical Reduction in Buildings

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5.1 General Context
5.2 Definitions
5.3 Trade-offs and the Lowest Option
5.4 Case Studies
5.5 The Secondary and Tertiary Benefits
5.6 Summary and Conclusions

 

 
Key Principles

1. It is possible, through trade offs, to provide a non-toxic specification to the majority of buildings – unless building prices are already at rock-bottom.

2. Trade offs can come from adding value through design, reduced service costs or through attention to the supply chain.

3. Immediate financial benefits can be realised through improved health (reduced medication), increased productivity, and reduced absenteeism levels in healthy buildings.

 

 
5.1 General Context

It is important to note that there are very few studies which have looked at the costs of green buildings. A comprehensive search has identified only one (from Austria) that has looked rigorously at the cost of third party (vetted) healthy materials.

Most of the studies have looked at the criteria which are of most relevance to the BREEAM and LEED labelling schemes and healthy materials have a low priority in both, compared to energy issues.

The studies do not isolate the health credentials of the materials and associated costs.

It is misleading to seek to take single elements from the details in section 6 (which are for illustrative purpose and not proposals) and price them out against alternatives as this ignores the trade-off options.

 

 
“Estimation procedures can often be found wanting when looking at individual green features, which can be picked off one by one as not cost effective, while they would hang together as a package” [76]
 

 
5.2 Definitions

Cost, price, value and affordability are ubiquitous terms in the Construction industry. They all have different meanings yet they are too often used interchangeably.

Cost discussions, in terms of sustainability, have tended to introduce cost-in-use (process) as well as first-cost (product) as part of the debate. In the case of a developer the cost of buying the site and constructing a building will be different from the price it is sold at (routinely by about 20%).

The issue of value is significant, because quality is a sustainability issue – in terms of fitness for purpose, robustness, longevity and health – which may or may not be delivered for the same price, depending on the skill and intent of the individual developer.

Affordability is now virtually synonymous with building more cheaply and at a lower quality than preferred. Importantly those on the lowest incomes are the most vulnerable to poor quality indoor climate.

5.3 Trade-offs and the Lowest Option

The debatable perception that green buildings cost more, in capital terms, dominates the public domain. Therefore, the tendency has been to seek to argue the case for green buildings on a ‘cost-in-use’ basis, where the consensus is that they do indeed pay back, even in narrow financial terms, and that this pay-back can be even greater where social and environmental costs are also accounted for.

The reality from a range of studies seems to be that, for low budget buildings, incorporating green specification without cost penalty is indeed very difficult. Nevertheless, for the vast majority of buildings above the lowest cost threshold, there are sufficient trade-offs available to specifiers to bring green buildings into line with conventional yardstick costs. These trade-offs vary but include adding value through design, reducing servicing costs or simply attention to the supply chain. Where these trade-offs are not taken account of then capital costs are generally found to increase by 1 – 7 %. Most of the studies summarized in the illustration, are looking at the whole range of green specification and not just the cost of healthy materials. Further inspection of the data indicates that the additional cost of non-toxic materials on its own would be likely to account for less than half this figure – in the case of the Ludesch project (see over) this was found to be below 2%.
 

The Cost of Green Buildings (above) is set against a 100% norm line, which represents the conventional building cost benchmarks, set individually by each of the studies. [77]
 

5.4 Case Studies

5.4.1 Town Centre Local Municipality Mixed-use Building, Austria

In the case of the £3m Town Centre development in Ludesch, built in in the Vorarlberg area of Austria in 2005, the clients commissioned a parallel study, during the construction period, to establish the additional cost of adopting a very high quality of Passive Design and a Healthy Building materials specification (see illustration for key materials choices). The research report identified the additional costs for the vetted healthy building materials (third party reviewed by IBÖ, the Austrian institute for Building Biology) to be a maximum of 1.9% over conventional costs, with a cost-in-use benefit that paid for itself in the first few months of occupation. (This sum does not include for the cost for the third party vetting of the materials for their health credentials). Given the nature of the materials identified in the table and their availability in the UK, as at January 2008, the percentage additional costs are transferable and equivalent to UK costs.
 

 

Ludesch Town Centre Eco-Building
Cost issues	Extra cost for eco materials
	Euro	GBP
Builderwork structural
construction carpenterwork
plywood instead of OSB	6507	£ 4,555
Hemp instead of mineral wool	3447	£ 2,413
Cellulose instead of rockwool	724	£ 507
sheepswool instead of hemp	869	£ 608
extra for knot-free wood	7298	£ 5,109
Builderwork technology
heating system
piping in stainless steel	2977	£ 2,084
higher pipe lagging standard (natural material)	861	£ 603
sanitary system
piping in stainless steel	3326	£ 2,328
higher pipe lagging standard (natural material)	1010	£ 707
low voltage electrics
Cable for energy monitoring	3990	£ 2,793
EMF isolation installation	6390	£ 4,473
trunking and support	19870	£ 13,909
Building fitout
joiner work
Walls + floors Sheepswool instead of mineral	4026	£ 2,818
Movable cross walls massive wood erection	2944	£ 2,061
dry lining sheepswool instead of mineral wool	18000	£ 12,606
Sheepswool caulking to wooden windows	888	£ 622
Total extra cost of ecological Materials	83127	£ 58,196

“Neubau ökologisches Gemeindezentrum Ludesch”
Wehinger, Torghele, G. Mötzl, et. al. Bundesministerium fur Verkehr, Innovation und Technologie May 2006
 

 
5.4.2 Two Sports Centres

Two £3m sports facilities, each with a 20 metre swimming pool and a three court sports hall, were constructed simultaneously during 1995-6 in central Scotland within 40 miles of each other. One was built to a high standard, but without regard to green principles; the other was built to an equally high standard but incorporating dynamic insulation, hygroscopic finishes and a healthy materials specification (mid to deep green) including mineral paints, linoleum and clay tile finishes. The centre with the green specification included for PVC, formaldehyde and VOC free materials and products, and was less expensive than the centre with the conventional spec. by £10/m2. This was achieved not by reduction in standard, but by careful trading-off of the more expensive items of specification in 1995 (insulation material, dynamic insulation system, paint finishes, etc) against a specification with a reduced services content. The above comparative information on construction costs for these two projects is via the QS company that was involved in both projects. [78]
 

5.4.3 A Visitor Centre

A £2m visitor centre was built in West Scotland in 2002 and, by careful design and selection of materials, including home grown timber, biomass fuel heating, natural ventilation, breathing floor, walls and roof construction, demountable (nail-free) detailing new British slate roofing, low flush wc’s and waterless urinals, was delivered on a par with similar facilities. Its M+E content was reduced via a strategy of passive design, superinsulation and airtight construction to 9% of the capital cost (as against a norm of around 25%). The 16% trade-off in unused heating, ventilation and electrical technology was used for the higher quality fabric, including a high standard of healthy building materials. The healthy specification included for zero PVC, formaldehyde and VOC content in materials. It included natural and untreated timber inside and out, mineral paints, cellulose fibre insulation, sheepswool caulking around windows and linoleum floor covering. Unlike the Ludesch building no detailed analysis or third party vetting of materials was undertaken. The above information has been derived from the architects and QS. [79]
 

5.4.4 Industrial Eco-Park

Scottish Enterprise commissioned research into the provision of sustainable light industrial units. The design team considered four options, standard, light green (minimal green spec.), mid green (moderate green spec.) and deep green (high level of green spec.) The resultant study established that the deep green option was 20% more expensive than the standard (low-cost) option, as there was very little to be traded off. The developer, who was being reimbursed only a proportion of the additional cost, perhaps surprisingly and somewhat bravely, chose the deep green option and the eventual build costs bore out the research. All of the units were let immediately, upon completion, to companies operating their businesses in a sustainable manner. This may well have been a tertiary benefit of the specification in a location where light industrial units were not in particularly high demand.

In looking back at the study for the purposes of this publication we have estimated that those additional costs that can be assigned strictly to materials and products, probably account for about 50% of the total additional cost. However, even here there were options for potential savings (eg cellulose fibre instead of the sheepswool that was installed). This would probably bring the additional costs, even in this low budget situation, to around 5%.
 

Histogram Forfar Eco-Park. The left hand column is in £ sterling for totals and one tenth of these figures for the Cost/m2

5.5 The Secondary and Tertiary Benefits
 

 

“While the environmental and human health benefits of green buildings have been widely recognized, this comprehensive report confirms that minimal increases in upfront costs of about 2% to support green design would, on average, result in life cycle savings of 20% of total construction costs – more than ten times the initial investment.” [80]
Adams
 

 
A study into Healthy Indoor climate design and productivity has indicated dramatic reductions in:-

• Acute Respiratory Illness (ARI) of 23%-76% (worth $6bn to $14bn a year in the USA.)
• Allergies & Asthma of 8%-25% (worth $6bn to $14bn a year in reduced health costs and $1bn to $4bn in economic gains)
• Sick Building Syndrome (SBS) of 20%-25% (worth $10bn to $30bn a year)
• Direct Productivity gains 0.5%-5% (worth $20bn to $200bn a year). [81]
   

5.6 Summary and Conclusions

The skilled practitioner will trade off the higher price of certain sustainable materials by moving towards passive design and away from highly serviced buildings by use of careful orientation, massing design, and detailed specification. The use of passive design, breathing wall construction, hygroscopic finishes, natural ventilation, the elimination of air conditioning and similar measures can all be used to reduce prices.

The foregoing is of course going to be affected by the type of building in which the detail is used. It should also be born in mind that the initial cost of a building is relatively small in relation to its whole life cost and as such increased costs of construction will not be particularly relevant over the life of the building unless they are of considerable magnitude. Costs require also to be considered holistically, as the tertiary benefits (improved health, reduced absenteeism) will accrue to the building owner and/or society as a whole.
 

 
“We are pleased to report that most healthy materials now cost no more (and sometimes less!) than conventional products, thanks to increased demand and production. Labor costs may rise slightly if the builders are not familiar with the materials or with healthy building techniques, but even then the total increase is typically just 1-3% of total cost to build.”
(US Web advertisement February 2008) [82]

 

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Footnotes:

76. Bordass, B. (2000) Cost and value: fact and fiction, Building Research & Information Volume 28, Issue September 2000

77. References for this table are:-
LEED - The Costs and Financial Benefits of Green Buildings. A report to California’s Sustainable Building Task Force, Greg Kats October 2003.
BREEAM - Putting a price on Sustainability, Cyrill Sweet BRE trust 2005
Ludesch - “Neubau ökologisches Gemeindezentrum Ludesch” (New ecological community centre Ludesch) Wehinger, Torghele, Mötzl, et. al. for the Austrian Federal Ministry for Transport, Innovation and Technology, 2006
Gaia Industrial - Cost Study for Forfar Eco-park, Gaia and Ralph Ogg for Scottish Enterprise 2002
Gaia – In-house feedback studies vetted by Ralph Ogg & Ptnrs.
Solarbau Study – per Joachim Eble Architects, Tübingen, Germany 2000.

78. Ralph Ogg and Partners

79. Ibid

80. Kats G., et. al. (2003) The Costs and Financial Benefits of Green Buildings - A Report to California’s Sustainable Building Task Force

81. William F.J., (2000), Health and Productivity Gains from Better Indoor Environments and Their Relationship with Building Efficiency, Annual Review of Energy and the Environment, Vol. 25 pp. 537-566

82. www.architecturalhouseplans.com/healthy_homes/

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