II – A NEXO E STADÍSTICO
CONCEPTOS UTILIZADOS EN LOS CUADROS “APROXIMACION A LAS CAUSAS DE LA VARIACION DE LA RECAUDACION”
Objective
• to identify platforms for the comparison of environmental strategies for buildings.
Comprehensive assessment methods can be used to rate buildings for overall environmental performance, something which goes beyond the purpose of simulation software. Examples of available assessment systems: Green Building Challenge (GBC) GB Tool, BREEAM Green Leaf rating system, and US Green Building Council
(USGBC) LEED™ rating system. GBTool Software
The Green Building Challenge (GBC) is an international collaborative effort that has grown to include over 25 countries. Its purpose is to create a forum for the international exchange of green building strategies. As part of the international GBC process, Green Building Tool
Software (GBTool) was designed to be the
operational software for the GBC assessment framework. Nils Larsson of NRCAN and Ray Cole of UBC were the authors of the GBTool. It is a sophisticated and subtle spreadsheet that allows participating countries to selectively incorporate ideas or modify their own building assessment tools. The GBC and GBTool processes are valuable research and development initiatives which influence many nationally recognized systems in participating countries.
GBTool assesses potential environmental merits
of proposed buildings but it has no mechanism to evaluate constructed projects. The tool can be applied to offices, multi-unit residential and educational buildings. It is possible to simulate performance in areas such as energy consumption, estimate embodied energy and emissions, and predict thermal comfort and air quality. The tool compares a proposed design to the benchmark values defined by national teams. The strategies of the proposed design are weighed and scored to produce a final score. The weighing and scoring must be properly coordinated with the national teams for proper assessment of the proposed building.
The software has been implemented on an Excel spreadsheet and may be downloaded for evaluation and educational purposes. It is time intensive and therefore “costly” to create a complete assessment ($20,000-$30,000). The software has been developed by Natural Resources Canada (NRCan) on behalf of the GBC group of countries. It should be noted that this tool is not meant for commercial purposes. However, agreements may be worked out between potential users, the relevant national team and NRCan.
BREEAM GREEN LEAF Rating System
BREEAM/Green Leaf was created in 1998. Its simple approach addresses a broad scope of issues but nevertheless maintains the principles of credibility, affordability and efficiency. The program is based on the international BREEAM environmental criteria as developed by the Building Research Establishment in the U.K. The assessment procedure was modeled on the Green Leaf Eco-Rating Program for the Canadian Hotel Industry. ECD Energy, Environment Canada and Terra Choice produce the program.
This Canadian rating system was developed as assessment tool to be used by building owners and managers. It is appropriate for office buildings and multi-residential buildings which require a comprehensive assessment of environmental performance. In addition to global, local and indoor environmental issues, BREEAM/Green Leaf covers a several important tenant concerns selected from the BOMA Tenant Satisfaction Survey
1998. These selected issues are often associated
with tenant satisfaction and include thermal comfort, security and office layout.
Measurement and Verification Chapter 2.2
The system results in a comprehensive report with recommendations for improvements in operational savings and occupant health and comfort. It is a tool produced for the private sector, and a fee is charged to use it.
LEED™ Rating System V2.0
The LEED Green Building Rating System™ is a major program of the US Green Building Council (USGBC). The USGBC enjoys wide representation from the construction industry including product manufacturers, building owners, environmental leaders, design professionals, contractors, builders, utilities, governments agencies, building controls contractors, research institutions and the financial industry. The LEED™ program is a voluntary, consensus-based, and market-driven building rating system based on proven technology. It evaluates environmental performance of a series of criteria over a building’s life cycle. LEED™ is based on accepted energy and environmental principles and aims at striking a balance between accepted practices and new sustainable technologies. LEED™ is a self-assessing system designed for rating new and existing commercial, institutional, and high-rise residential buildings. It is a “feature-oriented” system where credits are earned for satisfying criteria. Different levels of green building certification are awarded based on the total credits earned. Section 8 of this manual describes the LEED tool in more detail, as it is likely to become the standard tool in North American for Building Assessment.
Summary of Strategies for Use across Canada
• Use assessment tools to rate buildings. • Increase marketability of a building by
promoting its environmental rating.
Resources
GBTool Software
www.greenbuilding.ca/gbc2k/gbc-start.htm
BREEAM GREEN LEAF Rating System
www.breeamcanada.ca
LEEDTM Rating System
www.usgbc.org
Commissioning
Objective
• to provide the optimal settings for all building systems.
Commissioning procedures should be in place to ensure that a completed building is performing as designed and that the construction adheres to the drawings and documented design intent. Commissioning should occur during construction as well as during occupancy.
A commissioning agent should be present during the construction phase to ensure the calibration of various systems. This is more cost effective prior to occupancy of the building. The commissioning of green buildings includes all systems, such as mechanical, lighting, water, controls, thermal performance, the building envelope and natural systems. Natural systems which may need commissioning include the proper functioning of operational windows for natural ventilation, passive solar systems such as louvers, or daylighting features such as light shelves.
One of the most important stages of com- missioning occurs in post-occupancy. Post- occupancy commissioning is valuable because sustainable design considers the entire life cycle of a building, from construction to deconstruction. As previously mentioned, the operation of a building consumes the most energy in the useful life of a building. Changes in staffing, building use, or systems failure, can result in significant changes to the performance of a building’s systems. They may not be functioning as designed. Ongoing measurements and verification through- out the life of a building optimize performance and permit adaptation of building systems to changes. For example, the slightest improvement in the performance of a building with respect to water consumption or energy use, when calculated over a 50 or 75 year period, will account for enormous savings.
Additionally, commissioning should include the training of building users for ultimate building operation. Post-occupancy commissioning adds additional cost to professional fees; however, these costs can be justified and recovered through increased energy efficiency, increased occupant well-being and improved tenant satisfaction. Ensuring the proper functioning of all systems also reduces maintenance and repair costs. Post-occupancy measurement and evaluation is not typically included in conventional design team services.
The intent of a well developed commissioning strategy is aligned with long term sustainable goals and targets. Commissioning subconsultants or specialist firms can be retained by the client to carry out this task, however, the IDA team should ensure that commissioning agents understand and share the sustainability goals of the project.
Summary of Strategies for Use across Canada
• Include a commissioning agent in the design team.
• Document and review the design intent of all systems.
• Develop a commissioning plan as early as possible.
• Provide an operation and maintenance manual.
• Prepare a commissioning report. • Provide the means for continual
environmental monitoring.
Resources
International Performance Measurement and Verification Protocol
www.ipmvp.org
ASHRAE (1996) Guideline 1: The HVAC Commissioning Process
www.ashrae.org
Measurement and Verification Chapter 2.2
Chapter 2.0 - Green Building Design Methodology
Chapter 2.0 - Green Building Design Methodology
2.3 Regulations,
Linkages and
Tradeoffs
2.3 Regulations,
Linkages and
Tradeoffs
One of the biggest obstacles to achieving more sustainable buildings is the implementation of new and different processes for development, financing, design, construction and operations. Incorporating green building technologies requires a fundamental shift in the attitudes of all participants including a deep respect for the environment.
Building industry professionals can play a part in influencing public opinion and, ultimately, all related regulations by promoting successful green building technologies to the public, clients and fellow professionals.
Regulations, Linkages and Tradeoffs Chapter 2.3
SDCB 101 – Sustainable Design Fundamentals for Buildings