This article is based on the article in REHVA Journal published in August 2012 and it describes the methodology of validation of indoor air systems in Scandinavia. Ventilation systems are certified as energy-efficient product and installed in buildings, thus one would expect just to push the green button and get an excellent indoor air. Might not be the case if the commissioning was omitted!
The complete construction program of a building includes many people and companies involved in design and construction of a building along with installation of systems. This all costs money and the indoor air system, or HVAC systems or technical installation respectively, play a major role in building costs. These costs are related to acquiring, installing and maintaining the installation system, and can be split to initial and running costs. All installation system can be functionally tested after completion of building to prove functional and operation abilities in low-energy manners. In Scandinavia is very common to use the quality control way to ensure that the new systems will be functional to ensure well installed and well functional systems. Yet, it seems that the quality control is not enough for all types of building, therefore the focus has shifted and the commissioning is used in buildings.
The methodology of commissioning includes inspections and tests of installed technical systems and randomly sampled rooms and sections throughout the buildings. This includes measuring the installation systems along with airflow and directions with energy in the air and transport of such energy. The aim is to facilitate correct energy calculations which can be then scaled up for the entire building.
This verifies that energy calculation results are met and the owners and/or tenants are ensured that the installations are working properly. Also this clearly ensures that every component delivers what the building installers promised. This all is tight up with money as this process ensures that the running costs are at the correct level.
In Sweden since 1991, the compulsory ventilation check (OVK) is made before the building is in daily use, also repeated regularly to keep the standard and when the ownership of a building is changed. This check ensures that the ventilation works as intended and the legal demands are fulfilled.
In Denmark this commissioning is in the process of implementation in to DS447 Standard for Building Ventilation as part of the Building Code to ensure the higher demands for indoor air installations. This all connect to the legally-demanded energy frame which sets the limits for energy supplied for heating, ventilation, cooling and hot water supplies and lighting at the required level.
In Norway, the ventilation stands for 10-15% of the energy budget for residential and 30-50% for non-residential buildings. In Norway it is very common to build to a passive house or low-energy standard, and part of these standards is an energy certification requiring the actual performance of the installed systems. The Norwegian Energy Certification System (ECS) demands an energy certificate for all new buildings and all buildings being sold or rented. The Energy Inspection is required every fourth year with the first time within two years after building/handing over.
In Finland, the National Building Code of Finland requires ventilation system commissioning at the minimum level of air tightness of duct work and measurement of supply/extract air flows. Practically mandatory requirement is to install heat recovery in ventilation and demand certain emission levels in good air design practice.
And why use the commissioning and why it should and has to be mandatory? It is simple: to get control over the performance of technical installations. If one is to install a certified product, one must ensure that it works in the most efficient way to prevent energy loss and to achieve a good indoor environment and to save energy and money respectively.
Photo describes the definition of commissioning http://en.wikipedia.org/wiki/Commissioning_management_systems