Building Evaluation Tools

VERDE. Building Evaluation and Environmental Certification Method


In the past few years, the concepts of “sustainable or green building” have evolved, incorporating new notions and concepts.

Due to several factors like climate change or a shortage in natural resources, we are witnessing an increase in the environmental awareness of both citizens and designers. This has lead us to look beyond traditional construction methods, taking other problems into consideration, such as energy saving or material selection, following ecological criteria.


Nowadays, some ecological and energetic saving measures are generally taken by designers, depending on the context and location of the building, its characteristics and their own knowledge on the subject. Nevertheless, it is more complex to assess whether these measures imply that the building is truly innovative, eco-friendly and sustainable, making it worthy of obtaining an Environmental Certification. At any rate, it becomes clear that introducing one single element is not enough to confirm that a building is actually sustainable.


Considering these arguments the Technical Committee at GBCe  has put together  criteria and established rules to define the requirements and limits a building must meet to be qualified as sustainable, and therefore obtain a GBC España Certificate-VERDE.

The evaluation system is based on a feature evaluating method, in accordance with the CTE (Código Técnico de la Edificación, Technical Building Code) and European Guidelines.  At its core are bio-architecture principles: the building’s respect for the environment, whether it is compatible with its surroundings and the high comfort and quality of life levels required for the users.


Evaluation Criteria

The evaluation criteria are grouped into subjects, as follows:


 A. Site Selection, Project Planning and Development

  • Recycling strategies for the project or community
  • Autochthonous plants
  • Atmospheric light pollution

B. Energy and atmosphere

  • Use of non-renewable energy resources in the manufacture of building materials
  • Use of non-renewable energy resources to transport the building materials
  • Reduction of operating energy
  • Reduction of peak electric loads
  • Provision of on-site renewable energy systems
  • Strategies to reduce the emission of photo-oxidants and NOx substances
  • Strategies to reduce substances aggressive to the stratospheric ozone layer, from building materials and HVAC systems

C. Natural Resources 

  • Design measures to reduce use of potable water for occupancy needs 
  • Rainwater storage for later reuse
  • Design features for a split grey/potable water system for later reuse
  • Natural impact and hazardous waste generated by building materials used
  • Demolition, dismantling, reusage and recycling strategies
  • Natural impact and hazardous waste generated in the construction process


D. Indoor environmental Quality

  • Removal, before occupancy, of pollutants emitted by new interior finishing materials

  • Indoor air CO2 concentration

  • Air movement in mechanically ventilated occupancies

  • Effectiveness of ventilation in naturally ventilated occupancies

  • Air temperature and relative humidity in mechanically cooled occupancies

  • Air temperature in naturally ventilated occupancies

  • Day lighting in primary occupancy areas

  • Glare in non-residential occupancies

  • Illumination levels and quality of lighting in non-residential occupancy design

  • Noise attenuation through the exterior envelope

  • Transmission of facility equipment noise to primary occupancies

  • Noise attenuation between primary occupancy areas


E. Service Quality

  • Spatial efficiency

  • Volumetric efficiency

  • Provision and operation of an effective facility management control system

  • Capability for partial operation of facility technical systems

  • Degree of local control of lighting systems in non-residential occupancies

  • Degree of personal control of technical systems by occupants

  • Ability to modify facility technical systems

  • Strategies to maximize adaptability of structural type and payout for the future functional requirements

  • Strategies to minimize constraints imposed by floor-to-floor heights on future functional requirements

  • Strategies to minimize constraints imposed by building envelope and technical systems for future functional requirements

  • Adaptability to future changes in type of energy supply

  • Development and implementation of a maintenance management plan

  • On-going monitoring and verification of building performance (energy and water)


F. Social and Economic Aspects

  • Access for physically handicapped persons

  • Access to direct sunlight from living areas of dwelling units

  • Access to private open space from dwelling units

  • Visual privacy from the exterior in principal areas of dwelling units

  • Access to outside views from work areas

  • Minimization of construction cost

  • Minimization of operating and maintenance cost

  • Affordability of residential rental or cost levels




Climate Change
kg CO2 eq per year
Increase in UV radiation at ground level
kg CFC11 eq year
Soil fertility loss
kg SO2 eq per year
Aquatic life loss
kg PO4 eq per year
Health and cancer risk
kg C2H4 eq per year
Changes in local biodiversity
Exhaustion of non-reweable energy resources, primary energy
Exhaustion of non-reneweable energy resources, other than primary energy
kg material
Exhaustion of potable water
Land use
Soil exhaustion due to non-hazardous material disposal
Hazardous waste storage or disposal 
Radioactive waste storage or disposal
Health, well-being and productivity of users
Financial risk or benefit for investors – Life cycle cost


Criteria and Impact Quantification


A benchmark, or reference score, is assigned to each criterion. They are set based on the revision of the laws or regulations in force, the performance analysis of the surrounding buildings.

The score goes from 0 to 5, in the following order:
  • 0 reference value level that implies compliance with current legislation or common practice
  • 3 value level implying good practice
  • 5 value level implying the best possible practice with an acceptable cost
The final score will be obtained by comparing and adjusting the impact reduction in relation to the reference building.
The load assigned to each impact is related to the significance of such impact on a worldwide scale, at global level, and to the local environment existing situation, at regional level.

At present, the assigned load for the several impact categories follows indications from the “OSE Report on Sustainability in Spain 2007” and the “MMA Report on the Environmental Profile in Spain 2007”.


Evaluation Results

valuation results are based on the environmental impact reduction of the evaluated building compared to a reference building, as is shown in the following chart:




By applying the adjusting rates for the different criteria and impacts a final score is given to the building, ranging between 0 points, minimum, and 5 points, maximum.

Depending on the final score a Certification Level is assigned to the building, as explained in our section  Certification Levels.



Tools for VERDE Environmental Certification.

Through this document you can obtain information in detail about the method and evaluation process of the VERDE tool . (download pdf).

 Currently, several tools exist that, parting from similar principles, allow building evaluation and subsequent certification.