ReUSE WP1: Barriers and opportunities. 2 nd general meeting in Tampere, Petr Hradil VTT Technical Research Centre of Finland

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1 ReUSE WP1: Barriers and opportunities 2 nd general meeting in Tampere, Petr Hradil VTT Technical Research Centre of Finland

2 2 Outline 1. Case studies 2. Reusing barriers Economic barriers Social barriers Environmental barriers Technological barriers 3. Reusing opportunities Components for reuse Reusing potential Business models Life-cycle study of steel element (LCA + LCCA) Dynamic life-cycle study of wood housing (DLCA) 4. Conclusions

buildings in 10 cases Office buildings in 7 cases Housing in 20 cases

3 3 Case studies 45 case studies from 1975 to 2011 Steel reused Timber reused Concrete reused in 16 cases in 4 cases in 25 cases Industrial buildings in 10 cases Office buildings in 7 cases Housing in 20 cases Commercial buildings in 4 cases Schools & museums in 6 cases Religious buildings in 2 cases

4 4 Barriers for reusing Economic barriers Usually it is difficult and costly to start business with reusing building components. (A1) Cost - The overall cost of reusing is often higher than building traditionally from new or recycled materials. Introducing product to the market may require expensive certification including material tests. The design cost is increased by the additional adjustments/refabrication during the construction from old elements and the deconstruction planning for the new buildings. (A2) Market - There is small market of second-hand elements. The lack of recovery facilities (salvage yards) for reused element and the lack of information about available components from planned and on-going demolitions prevent reusing in a larger scale. (A3) Coordination - Clients may reconsider using old elements in their building because the coordination of collecting elements from the demolished building or salvage yard is more costly than the traditional sources. Moreover, it is difficult to find companies specialized in deconstruction, designers willing to design from used elements and construction companies willing to build from used elements. (A4) Diversion to the other streams - It is often cheaper to landfill materials or to recycle them. Accessibility to landfills which have low tipping fees prevents investing into waste recovery. (A5) Insurance - The price of insurance policy for reclaimed building elements may be higher, even if the safety of the building is usually guaranteed following the same design codes as for new buildings.

5 5 Barriers for reusing Social barriers Designers, contractors and property owners do not have enough information and rules for planning and execution of reusing project. (B1) Legislation - The legislation is new (not tested in practice), scarce or missing. Some legislation is discouraging reusing by very high requirements on documentation and certification of building elements. It may be difficult to get building approval from local authorities if the second-hand elements are used. There is not clear goal in EU policies for implementation of component reusing. (B2) Standards - There are inadequate rules for design, deconstruction or product certification. The design standards do not recognize the difference between new and reused component. (B3) Awareness - The reuse concept is not widespread and may be difficult to accept by the industry. The ways of reusing should be more explained in specialized seminars/courses. There is not enough public information about reusing in media (internet, journals ). The building industry is conservative and new concepts and practices are adapted slowly. (B4) Perception - People have generally negative opinion towards second-hand materials. With the exception of wood and some worn bricks and tiles, it is believed that the new component is much more valuable that the used one. (B5) Health & Safety - Old building elements may contain hazardous materials. Deconstruction requires more manual labour than demolition, and therefore it is associated with higher safety concerns. Carrying and lifting old elements on the building site may be more risky than the new elements.

6 6 Barriers for reusing Environmental barriers It is not clear if the environmental benefits are not overridden by storing, additional transport, new technologies and practices. (C1) Impacts - Reusing is not always superior to recycling or other waste treatment considering the whole material and product life cycle. The life cycle performance of the building is sometimes not studied at all. (C2) Transport - The transport and handling of components may have considerable environmental impact. The salvaged components are sometimes transported over huge distances. The site-to-site transport mostly requires trucks that are not very environmentally efficient. Some building parts are unnecessarily transported and never used since the bad quality of component is often not recognized before it arrives to the site.

7 7 Barriers for reusing Technological barriers Technologies for reusing are mostly developed, however not used in the full scale. (D1) Products - Current building products are often not suitable for reusing. Designing new building from existing elements is very demanding. Trusses and frames are very large and difficult for handling. Reusing of the complete building units gives little flexibility to the architects. (D2) Materials - Structural materials are usually combined in such way that it is difficult to separate them at the end of the building service life. The durability is an issue for life expectancy of some elements. Joints may be problematic (glued, nailed). The recycling process (collecting scrap and melting) is already well-established for metals and it would be difficult to implement any alternatives. (D3) Applications - There is a lack of knowledge of possible alternative applications of particular element or possible alternative elements for particular application. Sometimes it is difficult to find a planned building of the same type. Elements (even if they have sufficient strength and quality) don't have optimal shape for structural use. E.g. rotor blades are not straight; rails are not structurally efficient as beams.

8 8 Components for reuse (timber) Framing Panels Joists Roof girders Solid/structural (finger jointed KVH), glued and glue laminated timber cross-laminated timber (CLT) or light frames Laminated or composite members usually fitted with endjoints. More complex structural systems

9 9 Components for reuse (steel) Beams and columns Panels Joists Roof girders Hot-rolled or coldformed profiles Sandwich panels Hollow beams, corrugated webs Usually trusses

10 10 Components for reuse (concrete) Beams and columns Panels Joists Roof girders Prefabricated members, difficult to trim/cut, sometimes grouted Prefabricated members, difficult to trim/cut, sometimes grouted Can be prestressed, usually grouted More complex structural systems

buildings Blocks of flats buildings 1 Timber 38% 2% Steel 8% 3% Concrete 54% 95%

11 11 Components for reuse (reuse potential) Reuse potential Timber Steel Concrete Framing (beams and columns) Panels Joists Roof trusses Materials in In all buildings Blocks of flats buildings 1 Timber 38% 2% Steel 8% 3% Concrete 54% 95% Source: 1 Poutiainen 2013, Rakennusjätteen vähentäminen ja hyödyntäminen korjausrakentamisessa

70 % 88 % Concrete 95 % Steel 99 % Timber 42 % Concrete: Steel: Source: 1 VTT

12 12 Material recovery Finland % of waste 1 Sorted 1 Recovered 1 (total) UK Recovered 2 (total) Concrete 35 % 70 % 84 % Steel 15 % 75 % 91 % Timber 35 % 70 % 88 % Concrete 95 % Steel 99 % Timber 42 % Concrete: Steel: Source: 1 VTT Directions of future developments in waste recycling 2 steelconstruction.info Timber:

13 13 Material recovery Finland % of waste 1 Sorted 1 Recovered 1 (total) UK Recovered 2 (total) Concrete 35 % 70 % 84 % Steel 15 % 75 % 91 % Timber 35 % 70 % 88 % Concrete 95 % Steel 99 % Timber 42 % Good practice Standard practice Good practice Best practice Concrete 75 % 95 % 100 % Steel 95% 100 % 100 % Timber 57 % 90 % 95 % Source: 1 VTT Directions of future developments in waste recycling 2 steelconstruction.info

14 14 Reuse potential The potential is expressed as % of sorted material (this means 10% of reuse potential is in fact only about 7.04% of all C&D waste). Recovery Reusing Standard practice Good practice Best practice Concrete 5% 30% 66% Steel 5% 40% 75% Timber 5% 30% 50% 3 lives (2x reuse) 4 lives (3x reuse) 2 lives (1x reuse) The current state (estimated) Maximum from today s buildings (estimated) Maximum from buildings designed for reuse (estimated)

15 15 Reuse potential The potential is expressed as % of sorted material. Reusing Standard practice Good practice Best practice Concrete 5% 30% 66% Steel 5% 40% 75% Timber 5% 30% 50% UK Reused 1 (from recovered) Concrete 0 % Steel 6 % Timber 31 % Source: 1 steelconstruction.info Good practice

16 16 Business models Collecting in salvage yards Basic elements (wood framing, steel sections ) Direct re-selling Complex elements and systems (frames, trusses ) Producer s responsibility Special products (sandwich panels ) Product lease Temporary structures (expo stalls )

17 17 Life-cycle study (scope)

18 18 Life-cycle study (transport) Bolt manufacturer Steel hot rolled section producer Steel hot rolled coil producer Beam manufacturer Building site Dortmund (Germany) Ostrava (Czech Republic) Gala i (Romania) Boc a (Romania) Arad (Romania)

19 19 Life-cycle study (scenarios) Software: OpenLCA (open-source) LCI database: ELCD (free) Three scenarios were considered: (1) No reusing (material is only recycled) (2) 50% reusable content (2 lives/1x reusing) (3) 66% reusable content (3 lives/2x reusing) (4) 75% reusable content (4 lives/3x reusing) Assumptions: (1) 97% of steel is recovered (recycling or reuse) (2) Production of M20 bolt (with nut and washers) consumes approximately 0.35 kg of steel. (3) Bolts will be assembled during construction, but they were added to manufacturing stage for simplicity. (4) New or reused beam has to be cleaned (sanding) and painted before the transport to the building site. This process is also made in Boc a, but is separated from the manufacturing step because it uses different inputs in recycling and reusing scenario.

20 20 LCA study (results) Global warming potential (GWP 100a) 1.04 t CO 2 e t CO 2 e t CO 2 e t CO 2 e.

21 21 LCCA study (results) No reuse Reusing 1x Reusing 2x Bolt manufacturing Transport, bolts supply Transport, plates supply Transport, profiles supply Beam manufacturing, welding, cutting drilling Beam manufacturing, sanding, painting Beam remanufacturing, sanding, painting Transport, beam to site Beam construction Beam demolition Beam deconstruction Transport, beam from site Total costs Reusing is more expensive!

22 22 Dynamic LC study (model prototype) Wood waste 7.8 t CO 2 /unit released every year 16 % is landfilled 0 to 30 % is reused Landfill + 50 yr +50 yr 1 Building use 34 to 84 % is burned 35 m 3 of wood per housing unit +50 yr +50 yr +50 yr 20 % is recycled 0 to 30 % is reused Housing unit is a single small-family wooden house (100 m 2, 35 m 3 of wood) Reuse rate is changing dynamically from 0% to 30% from 2010 to (a) 2020 (b) 2050 (c) (1) Building use (material consumed in the simulated year and material released after 50 years) Structural timber Wood-based panels (2) Structural timber is produced if needed or disposed as low-quality wood if not used 2b (3) Wood panels are produced if needed or disposed as low-quality wood if not used 20 m 3 of structural timber per housing unit 1.3 t CO 2 /unit released 2a Sawmill (4) Low-quality wood is harvested if needed or sent for incineration if not used 8% 42% (5) Wood waste is incinerated in the end ~ 1.4 ha of land used per housing unit 9.1 t CO 2 /unit consumed Forest 50 % Low-quality wood

23 23 Dynamic LC study (preliminary results) Wood waste Landfill +50 yr 34 to 84 % is burned Simulation set-up: 7.8 t CO 2 /unit released every year 16 % is landfilled 0 to 30 % is reused + 50 yr 1 Building use 35 m 3 of wood per housing unit +50 yr +50 yr +50 yr 20 % is recycled 0 to 30 % is reused (a) One neighborhood of 80 wooden housing units. (b) Rotation length of the house is 50 years. (c) Simulation 100 years from (d) Target is 30% of reused elements (good practice) in 2020, 2050 or Structural timber Wood-based panels 2b 20 m 3 of structural timber per housing unit 1.3 t CO 2 /unit released 2a Sawmill 8% 42% ~ 1.4 ha of land used per housing unit 9.1 t CO 2 /unit consumed Forest 50 % Low-quality wood

24 24 Dynamic LC study (preliminary results) Simulation set-up: (a) One neighborhood of 80 wooden housing units. (b) Rotation length of the house is 50 years. (c) Simulation from 2000 to (d) Target is 30% of reused elements (good practice) in 2020, 2050 or Equals to driving one car 55 km a day for 10 years or 5 x around the Earth.

25 25 Conclusions - Reusing of building components needs to overcome serious barriers before it becomes fully competitive to the other options. - Certification of second-hand components seems to be the most important issue. - The most important parameter for predicting environmental benefits from reusing is the reusable content in the sorted waste. This has to be further investigated. - The most important parameter for predicting economic benefits from reusing is the cost of deconstruction. It is about 4x higher than demolition at the moment, but can be reduced in the future.

26 26 VTT creates business from technology

A study on construction and demolition wastes from buildings in Seberang Perai

A study on construction and demolition wastes from buildings in Seberang Perai Faridah A.H.Asaari 1, Hasmanie Bt Abdul Halim 2, M Hasnain Isa 1 1 School Of Civil Engineering, Engineering Campus, Universiti