Winwall Technology India Pvt Ltd (WTIPL) is a joint venture with Winwall Technology Pte Ltd, Singapore (WTPL) one of South East Asia’s oldest and most respected Façade Testing Labs. With over 25 years of experience in testing over 1600 projects across Asia WTPL is the most preferred testing lab for consultants and Architects in this part of the world. WTIPL was established in 2013 to cater to the growing Indian and Sri Lanka market and has successfully completed testing 63 projects in the last three years.
Mr. P. Jothi Ramalingam, Director, Winwall India has around 30 years of experience in the fenestration industry and is actively involved in creating awareness for façade testing and its importance to the Indian Building Industry.
“Marketing a Product without Testing is like driving a truck with your eyes closed” said a wise man once. Every iconic product introduced into today’s competitive market reaches the buyer after it is put through several levels of rigorous tests to evaluate its performance on the basis of established parameters and standards. This would also apply to building facades, doors, windows and handrails which are used extensively in today’s growing construction industry. More so because the failure of these products in a real time situations may result in a life or death situation for those living within and around the building.
As India’s economy begins to accelerate the shapes and sizes of buildings being conceived by new age architects and consultants become more and more complex. Therefore the aluminium frame work, in almost all cases, designed to hold the glass is specially extruded to suit the specifications of that project. Even though the structural calculations for the framework have been derived from established formulae using sophisticated software, the actual behavior of the product in a real life situation still remains uncertain.
Like every other product we use in our day to day life, the performance of facades, windows and doors too have been clearly defined by international standards like ASTM, AAMA, BS EN and AS NZ standards based on a few well established parameters. Every performance parameter has been arrived at after years of research and user feedback under different weather conditions. For example the allowable air infiltration for a fixed glazing as per ASTM E283 is 1.20 M3/hr/m2. If the air infiltration of a system installed is more that this acceptable norms then the energy wasted through increased air leaks will impact the air conditioning load which in turn is money going down the drain.
There are three major parameters which are used to evaluate the performance of a facade, door or window.
- Air Infiltration/Exfiltration
- Water Penetration
- Structural Performance
- Air Infiltration/Exfiltration
A facade, window or door is product manufactured by bring in different elements like aluminium profiles, epdm gaskets, ss screws, glass etc. Although each component of a facade comes with a test certificate from the manufacturer of that component the performance of that component as a part of façade or window system is what the end customer interested in. Air infiltration is a key parameter to measure the quantum of air leaking through the façade. The larger the leak the higher the noise coming in and higher the load on the air conditioning system in the building. The test is to measure the actual volume of air leak in the system and compare it with the allowable volume at a given pressure, to determine the performance.
- Water Penetration
The ability of the façade to effectively repel water from entering the building even during severe cyclonic conditions determines its efficiency. Water penetration tests are of three different kinds namely Static, Dynamic and cyclic. Static water tests are commonly used to determine the ability of a system to drain the rain water without overflowing into the building under a fixed differential pressure. Dynamic and cyclic water tests test the same parameters but by simulating cyclonic conditions. Any water coming in through the system is considered a failure.
- Structural Performance (Windload)
Every building whether it a high rise or low rise, is build considering the impact of the structural load due to the wind speed which impacts it. The geographical location, height and shape of the building determine the wind load that will affect the project continuously. Every external element of the building which is affected by the wind speed has to be designed on the basis of this key parameter. Since facades, windows and doors form a significant part of the building exterior it is important to check if the system can withstand the given wind loads. Structural performance test measures the deflections of every critical component of a façade system and compares it with allowable deflections to ensure that the system does not fail during high wind loads.
There are two kinds of testing performed on the facades before they are certified for a project.
- Off site testing – Done at the testing lab before installation.
- On site testing – Done in the site after installation.
During an offsite testing a performance mock up unit (PMU) sample is fabricated using the same materials specified to the exact dimensions of the specific building if it is a window or door and in the case of a curtain wall a minimum of three panel width and two floor height sample needs to be installed in the testing lab and for testing. The tests conducted in the laboratory are done to extreme conditions so that under day to day normal conditions the chance of failure is remote.
On site testing is done at site to check if the façade has been fabricated and installed as per mutually agreed methodology. Only air infiltration and water penetration tests are conducted during on site testing.
The chart given below gives the different tests and tests and standards commonly specified in India.
A tested and certified façade, door or window would ensure that the builder and final buyer of the building get value for their money while providing a safe environment for those who live within and around it.