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Not Just Another Façade Test. Actually Achieving Whole Building Air Tightness Makes a Huge Difference

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Not Just Another Façade Test. Actually Achieving Whole Building Air Tightness Makes a Huge Difference Not Just Another Façade Test. Actually Achieving Whole Building Air Tightness Makes a Huge Difference. What is the percentage of Energy Use for Heating & Cooling in Commercial buildings? New more energy efficient buildings 25% Typical Australian Office Buildings 40% Why should we care about The Air Barrier? • Air leakage (infiltration) impacts – Thermal Comfort of Occupants – Indoor Air Quality (IAS) – Structural stability/ integrity (Condensation) – Energy Efficiency • Air leakage and mechanical contractor – Air balancing / effective air distribution – Over sizing or Under sizing of plant – Can Disturb building control The Energy 3 Rs Remove Reduce Renewable What Drives Air Leakage On Commercial buildings? Getting what you paid for? • Bad modelling? • Bad operation? • Bad construction? Source: GBCA. August 2013. “Achieving the Green Dream: Predicted vs. Actual” 11 OK… so Where is the Air barrier? Defining the Air Barrier / Envelope Why worry about the Air Barrier? What’s Wrong with Our Buildings? • Air leakage (infiltration/exfiltration) is one of the key parameters affecting the performance of buildings and has been largely overlooked by the building industry. – Architects have not paid sufficient attention to detailing air barriers – Builders generally overlook the detail, and aren’t interested in the additional cost and effort required to remediate. – Trade contractors may not be aware of the significant effects from unsealed penetrations Building Leakage Points - Don’t just look for big holes. It’s a numbers game! Air tightness is a numbers game. 8m x 2mm = 160cm2 300m x 2mm = 6000cm2 Builders Lack of Awareness Builders Lack of Awareness If daylight is getting in, air is leaving Poor Trade Practice Poor Trade Practice What makes a good air barrier • Appropriate air permeability – Varies with building code/standard if specified – Appropriate Vapor permeability • Continuous over the entire building envelope – Seal gaps around penetrations (install before cladding) – Seal wall-to-roof joint – Seal wall-to-foundation joint – Seal around windows and doors • Withstands forces during and after construction • Durable over expected lifetime of building Aquatic Centres and Air Tightness • Lower Maintenance of HVAC system • Lower Maintenance on the building Envelope • Improve Longevity of the building structure. • Lower Energy use • Improve occupant comfort. • Prerequisite for implementing an advanced HVAC control system. Video of condensation in aquatic Building envelope remediation Building envelope remediation Condensation inside the envelope Building envelope remediation Where is the Air Barrier within the detail? Poor Air Barrier Detailing Where is the insulation? How does the membrane finish? How does the membrane fix to structure? How does the ceiling air barrier connect to walls? There will not be any wall when the membrane is installed with the roof, how will they be fixed/ stabilised? Where is the support for applying tape on membrane? Air Tightness Testing …what is it? • 3 main methods: • Tracer gas testing • Timing and cost • Using building’s own HVAC • Not reproducible • Blower door testing – Compartment Testing – Whole Building Testing – Façade Testing 35 What are the issues with these testing methods? • Tracer Gas – Long term multiple test is required to demonstrate performance under various ambient conditions • Using building’s own HVAC – Calibration of fans at various flowrates as installed is required. – Field calibration is particularly difficult for high-rise buildings – the effect of wind and stack effect in riser Blower Door Testing • Document the relative airtightness of buildings (are they leaky - tight - or somewhere in between). – What level of air tightness is too leaky? ATTMA TSL2 specifies good practice and best practice depending on the building type. – Allows for a comparable number to other buildings. • Help find air leaks by inducing air to move through all leaks at the same time (chemical smoke, IR camera, feeling with you hand, zonal pressures). • Determine the effectiveness of air sealing activities (compare before and after measurements). Blower Door Testing- Quality Control 42 Blower Door Testing- Quality Control • Minimum number of fans required for the test – Based on the envelope area and the target leakage rate. • Multi-point pressure test is required. • Preparation of penetrations in accordance with standards. • Verify ambient weather conditions • Fully automated blower door test to minimize human errors and real time monitoring of data quality. – Variance in data collection is virtually impossible to be detected in manual testing with multiple blower door fans. 43 What do we do on testing day • Close exterior doors and windows • Open interior doors • Seal constant-ventilation systems • Leave intermittent/ on demand ventilation open • Set up fans, computer, pressure gauges • For large building, setup may take a day or more • Verify ambient weather conditions • Run the test • Simple tests can be done in an hour • Complex tests can take a day 44 Tips to Achieve good outcomes • Have an air tightness champion on site. – Ensure trades understand where and what the Air tight building envelope actually is. – Single point communication – Frequent inspections – More inspections – Even more inspections • Well defined air barrier – Clear responsibility among all trades – in contract/specifications How Can Efficiency Matrix Help? • Pressurization testing of building at lock-up and completion. • Construction Stage Inspections and advise on remediation as required. • Conduct remediation work. • Certify permeability rate of building at completion. • Pressurization testing of air-conditioning ductwork/ plenums at commissioning of system. Our Experience with Buildings 20 years experience in building envelopes • Military Buildings • Isolation Rooms • Aquatic Centers • Oil Rigs • Office Buildings • Plenums (Underfloor or Room) • Data Centers (Including Fire Integrity) Building Envelope Permeability 25 25 20 20 15 15 m³/h/m² m³/h/m² at 50Pa 10 10 5 5 0 0 A B C D E F G H I J K L M N D* E* F* Building Air Tightness Testing Only Construction Stage Consultation and Air Tightness Test, Remediation and Air Tightness Test Target Auditing an Existing Building Air Tightness does not need to start with a test! Efficiency Matrix Defect Reporting Process • Insulation consistency Audits documenting exact locations of issues • Air Leakage audits, documenting exact locations of issues • Energy loss • Estimating Heating requirements, and projecting benefits of improving the building envelope. • Plugin Training and tools for existing inspectors Service Safe, Efficient & Effective Sealing from the Inside. HOW DOES IT WORK? Benefits from sealing air ducts 1. Enhanced Building Pressurization 2. Improved Indoor Air Quality •3. Lower Energy Costs •4. Meet AS4254 5. Help with re-commissioning and retro-commissioning eCAULKair HVAC duct sealing Aeroseal is an airborne sealant which reduces duct leakage by up to 98% • Typical rigid ducts leak up to 35%. The Australian Standard 4254 specifies leakage of 5% or Seal leaky ducts to save energy less. • Sealing the ducts allows for the HVAC fan to be operated at 50% less energy consumption. • Conditioned air gets to where you want it. New Construction Benefits ➢Reduce Call Backs – Real time verification of actual leakage ➢Replace duct work with risers ➢Increased success in passing duct leakage test during commissioning ➢Ensures both new and existing duct systems comply with engineers specifications ➢Ensures both high-, medium- and low-pressure ducts are efficient ➢Overcomes most installation issues ➢Three to five times faster than hand sealing ➢Exceeds the most demanding leakage limits Sealing Overview • Proven, patented technology • Seals ducts from the inside out – Reduces 90% of leakage • Can be applied to sheet metal ducts, masonry risers, speed- panel risers and plaster board risers. • Overcomes human shortfalls – Finds and seals all leaks – No access limitations – Duct wrap not removed • Verifiable & guaranteed Where do Ducts Leak? Overview of Application Application FAQs ✓ Can Seal gaps up to 15mm. ✓ Generally no duct cleaning required prior to application (unless build-up in duct is >3mm) Kitchen exhaust with grease needs to be cleaned ✓ Can be used with speed paneling/riser liner or masonry shafts ✓ No need to remove dampers ✓ Must isolate equipment (VAV, fans, units, coils) from sealant stream ✓ Must cover smoke detectors and in duct sensors ✓ Best applied when spaces are unoccupied and technicians have full access to rooms and areas to monitor sealing process Sealant FAQs • Vinyl Acetate Polymer – Base for chewing gum, hair spray and water-based paints – Remains Rubbery • Certified in accordance with AS1530.3 for: – Ignitability, – Spread of Flame, – Heat Evolved and – Smoke developed • Low VOC Content – Greenstar complied ✓ 2 hours to cure NOT Setting hard Installation Examples Healthcare Healthcare University of Ottawa Heart Research Institute Nemours Children Hospital Roudebush VA Hospital Winthrop Hospital Mayo Clinic New York University Hospital California Pacific / Sutter Health Hospital Arzanah Medical Complex, Abu Dhabi Military Higher Education Ohio State University Camp LeJeune Princeton University NavAir Command Center Syracuse University Newport Naval Training School UC Davis Fort Jackson Critical Applications Multi-Family / Office Bldg. Cleveland Art Museum Met-Life Bldg. U.S. House of Representatives Hyundai HQ Deep Panuke Oil Platform Summary of Aeroseal Benefits ✓Lower Utility Bills ✓Improve IAQ ✓Eliminate Pressurization Problems.
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