In recent years, timber has been considered as an alternative source of building material because of its sustainability and design efficiency. However, the cost competitiveness of timber buildings is still under study due to the lack of available cost information. This paper presents a comprehensive cost comparative analysis of a mass timber building mainly developed with cross-laminated timber (CLT). The actual construction cost of the project is compared with the modeled cost of the same building designed as a concrete option. The result shows that the construction cost of timber building is 6.43% higher than the modeled concrete building. The study further investigated the change orders associated with the project and found that the total cost of change orders contributed 5.62% to the final construction cost of mass timber building. The study is helpful to provide insight into the construction cost of typical mass timber buildings. It also can be used as a guide for the project owners to make decisions regarding their initial investments on a mass timber project.
This paper aims to develop an artificial neural network (ANN) to predict the energy consumption and cost of cross laminated timber (CLT) office buildings in severe cold regions during the early stage of architectural design. Eleven variables were selected as input variables including...
Composite structures use the advantages of two materials – timber and concrete – and improve the efficiency of a material application. Especially the concept of timber-concrete-composite ceilings has synergetic effects to achieve an effective ratio of thickness to span with high cost effectiveness simultaneously. Following the systematic...
The research presents a Carbon Value Engineering framework. This is a quantitative value analysis method, which not only estimates cost but also considers the carbon impact of alternative design solutions. It is primarily concerned with reducing cost and carbon impacts of developed design projects; that is, projects where the design is already a completed to a stage where a Bill of Quantity (BoQ) is available, material quantities are known, and technical understanding of the building is developed.
This research demonstrates that adopting this integrated carbon and cost method was able to reduce embodied carbon emissions by 63-267 kgCO2-e/m2 (8-36%) when maintaining a concrete frame, and 72-427 kgCO2-e/m2 (10-57%) when switching to a more novel whole timber frame. With a GFA of 43,229 m2 these savings equate to an overall reduction of embodied carbon in the order of 2,723 – 18,459 tonnes of CO2-e. Costs savings for both alternatives were in the order of $127/m2 which equates to a 10% reduction in capital cost.
For comparison purposes the case study was also tested with a high-performance façade. This reduced lifecycle carbon emissions in the order of 255 kgCO2-e/m2, over 50 years, but at an additional capital cost, due to the extra materials. What this means is strategies to reduce embodied carbon even late in the design stage can provide carbon savings comparable, and even greater than, more traditional strategies to reduce operational emissions over a building’s effective life.
The report describes a new structural system in wood that is the first significant challenger to concrete and steel structures since their inception in tall building design more than a century ago. The introduction of these ideas is fundamentally driven by the need to find safe, carbon-neutral and sustainable alternatives to the incumbent structural materials of the urban world. The market for these ideas is quite simply enormous. The proposed solutions have significant capacity to revolutionize the building industry to address the major challenges of climate change, urbanization, sustainable development and world housing needs.
Project contact is Paulo Tabares at the Colorado School of Mines
Cross Laminated Timber (CLT) is a mass timber material that has the potential to expand the wood building market in the U.S. However, new sustainable building technologies need extensive field and numerical validation quantifying environmental and economic benefits of using CLT as a sustainable building material so it can be broadly adopted in the building community. These benefits will also be projected nationwide across the United States once state-of-the-art software is validated and will include showcasing and documenting synergies between multiple technologies in the building envelope and heating, ventilation and air conditioning (HVAC) systems. However, there are no such studies for CLT. The objective of this project is to quantify and showcase environmental and economic benefits of CLT as a sustainable building material in actual (and simulated) commercial buildings across the entire United States by doing: (1) on-site monitoring of at least four CLT buildings, (2) whole building energy model validation, (3) optimization of the performance and design for CLT buildings and (4) comparison with traditional building envelopes. This knowledge gap needs to be filled to position CLT on competitive grounds with steel and concrete and is the motivation for this study.