Condensation

• Australian Institute of Architects Refuel Provider by Andy Russell
  in Condensation, Seminars & Events
  19 Jan 2012  | 1 Comment

   

  PGA joins the Australian Institute of Architects (AIA) Refuel CPD Provider Network Proctor Group Australia have recently been approved as a member of the AIA National Refuel Provide Network and offer a seminar on the subject of condensation which is a now a recognised activity that will accrue formal points towards the requirements of the AIA CPD policy and the requirements of the NSW Architects Registration Board’s Continuing Professional Education policy, the Tasmanian Building Practitioners Accreditation scheme and the Architects Board of Western Australia. ‘Formal' CPD activities either include formal assessment or have what is defined as ‘significant interaction’ between presenter and participant. Our one hour presentation on condensation offers 1 formal CPD point. Arranging a CPD seminar For more details on arranging a seminar please visit CPD Seminars here

  Seminar Outline Condensation Conundrums – Where to put your insulation, vapour barriers and breather membranes.   Building envelope design is no longer just about keeping out the rain and wind. We are now faced with the challenge of balancing the need to keep out or keep in, and let in or let out cool and warm air, daylight, fresh air, contaminated air, sound, fire and moisture as appropriate for all seasons and all times of the day. The drive for energy efficient buildings with improved air tightness and insulation has changed the dynamics of the building envelope as insulation, whilst keeping some surfaces warm, also keeps other surfaces cold. Sealing up the building can also prevent the safe passage of water vapour, resulting in potentially damaging condensation on these cold surfaces. Long perceived to be immune from such problems, ‘the lucky county’ has seen an increase in the occurrence and severity of condensation problems across disparate climate zones as standard designs start to fail. The ABCB and the AIA in recognition of this, recently published a Condensation Handbook to inform the industry about these risks and to promote best practice.
• Building Australia's Future - ABCB National Conference 2011 by Andy Russell
  in Condensation, Seminars & Events
  16 Jan 2012  | 2 Comments

  Australian Building Codes Board Conference, September 2011 The presentation slides from the conference are now available for view or download on the ABCB website. The Australian Building Codes Board held it's biennial Building Australia's Future Conference (BAF) on the Gold Coast, Queensland in September 2011.  Many thanks to the ABCB for giving me the opportunity to present on the subject of condensation.  Pushing the envelope - Have we considered condensation? Fortunately the hecklers kept quiet and the presentation on the content of the ABCB Condensation Handbook certainly generated a bit of interest for the remainder of the conference. I would highly recommend taking a look at some of the other presentations, particularly in the morning sessions on day 3. Phil Wilkinson, the Chief Executive Officer of AIRAH gave a very entertaining and graphic presentation on the consequences of poor maintenance of HVAC systems including the "Hall of Shame."    Advice from a plant lover - Making sure HVAC systems stay green  Dennis D’Arcy, CEO of the Insulation Council of Australia and New Zealand discussed the diminishing marginal benefit of ceiling and wall insulation in both heating and cooling climates.  Making the DTS work for you Tony Tannar of the Roofing Tile Association of Australia presented some very interesting findings from the ongoing research at the University of Newcastle.  Solar absorptance and energy efficiency - What role does solar absorptance of roof cover play in determining heating and cooling loads? This is an area of particular personal interest and the results seem to reinforce findings from William Miller's work at ORNL and the D-Air research group in Japan including at Kamisei Roof Tiles. It is not just a matter of the values for solar absorptance/reflectance of metal roofs and roof tiles but also about roof space ventilation both above and below the substrate or sarking. The findings of the research will challenge some "accepted" thinking in the industry and I hope will have long term implications for future roof design and product development and feed into getting a greater correlation between standards, requirement and actual performance. All the presentation slides can be found from links on the ABCB web site. http://www.abcb.gov.au/education-events-resources/national-conference/day-3
• Critical points in rain screen details by Andy Russell
  in Sustainability, Condensation, Global Building Envelope Practices
  12 Dec 2011  | 0 Comments

  Rain screens, while common in Europe and North America, have begun to emerge to a greater degree in discussions within the Australian architecture and design community. A rain screen system offers numerous benefits in moisture-management and energy-efficiency but when I dig deep into conversations over the past couple years with local architects, façade consultants, suppliers and installers there is a huge variety of perceptions on what “rain screen” actually means and what the key design components are. I recently came across an excellent document jointly published by the Ontario Institute of Architects and available for free for download from the Canadian Mortgage and Housing Corporation. Page 26 includes an excellent checklist of 10 critical points in rain screen details. Provision for water shedding at the outer cladding, away from joints, with drips under any projections to prevent water collecting at the building face. A cavity of appropriate width to allow pressure equalization across the cladding system and prevent capillary movement (allow for construction tolerances!). A continuous and effective (for example, airtight to a maximum air leakage of 0.1 L/s/m2) air barrier within the backup wall. Drainage of the cavity through continuous flashings and weep openings, and proper management of drained water. Adequate venting of the cavity provided through properly located openings in the cladding (appropriate ratio achieved between vent area and leakage of air barrier and seals). Additional provision for drainage at the backup wall (located on the “warm” side of the insulation to avoid condensation problems). Effective compartmentalization of the cavity at each building face with airtight seals, and additionally across the width of the façade as required (refer to calculations). Sufficient rigidity and/or structural support of the air barrier to resist wind loads and limit deflection. Sufficient rigidity of the cladding to limit deflection and resist wind loads as required. Special attention paid to water-resistance and drainage at building edges and parapets (areas subject to heaviest rain-wetting and wind pressure differences, where pressure equalization may not be achievable) The National Association of Home Builders (NAHB) in the US outline the advantages of rain screen It neutralizes physical forces inducing water intrusion. It is a simple, forgiving system with built-in, multi-layered redundancy, and It has integrated drainage and ventilation that accelerates cavity moisture removal. Rain screens prevent or reduce moisture problems in exterior walls, including siding rot and peeling paint. Thermal shock, solar driven moisture effects, and pressure forces are diminished. In high moisture environments, the additional cost and complexity of Pressure Equalized Rain Screen construction may be cost effective over the long term. Rain screen designs do not increase the cost of drainable EIFS and brick veneer wall systems. To install the air space behind the cladding in most assemblies, however, costs for furring or other spacer materials cause costs to increase. The few cents per square foot spent on a rain screen offer exceptional value to design professionals seeking liability protection, builders wanting to avoid call backs, and homeowners looking for comfort. The Proctor range of vapour permeable membranes ProctorWrap High Tensile, Air Tight and Black Label can play an important part in meeting these requirements and provide a continuous air barrier. In particular the Black Label has been designed with high UV resistance for use in open joint rain screen applications. One area of debate is if a flexible membrane can be relied upon as the air barrier in pressure equalized rain screen design without a rigid substrate. Point 8 above advises that a “sufficient rigidity and/or structural support of the air barrier to resist wind loads and limit deflection,” is required. Studies by the Institute for Research and Construction in Canada report that the performance of the air barrier system affects the ability of the wall assembly to achieve pressure equalization across the rain screen, by reducing the flow of air through the wall assembly, and greatly contributing toward reducing the air pressure differential across the rain screen. “Under dynamic-pressure conditions, recent IRC studies indicate that excessive flexibility of the air barrier system will result in fluctuations in the volume of the air chamber compartment. These fluctuations adversely affect the potential for rapid pressure equalization across the rainscreen.” Chown, G.A., Poirier, G.F. and W.C. Brown, “Designing Exterior Walls According to the Rainscreen Principle”; Technology Update No. 17, Institute for Research in Construction, National Research Council of Canada, 1998. http://www.nrc-cnrc.gc.ca/obj/irc/doc/ctu-n34_eng.pdf It is clear that in order to attain the full benefits of rain screen then we need at the outset a clearer understanding of the function of the rains screen and what is required for the building envelop to function as such. Download the full CMHC document here: http://www.cmhc-schl.gc.ca/en/inpr/bude/himu/coedar/upload/The-Rain-Screen-Wall-System.pdf
• In over your head? by Andy Russell
  in Condensation, Global Building Envelope Practices
  17 Nov 2011  | 0 Comments

  “One of the most difficult buildings to build is a building with a swimming pool because – wait for it –there is a swimming pool inside.”

  Is it any wonder that heated indoor swimming pool roofs in Australia tend to have a very short life span and are a constant source of moisture and corrosion related headaches for facilities managers and local authorities that need to ensure their facilities remain open and provide a safe environment.

  Next time you are at the local swimming pool take a look up the roof and keep an eye out for damp staining on suspended ceilings. If the foil faced insulation blanket is exposed, is it in good condition and continuous? At my local pool I was not surprised at what I saw. (see images) 

  The pool just down the road at Lane Cove has suffered corrosion, with the local council already down $1million in legal fees over the past 4 years as part of an action taken against the builders and architects.

  In Victoria, closure for refurbishment of the Collingwood aquatic centre was brought forward as the council was forced to close twice in six months because of problems with a 30 year old “ageing roof structure.”

  In Canberra, the original Australian Institute of Sport Aquatic Centre is on its third roof since 1984 after requiring major structural work in 2010 to resolve corrosion issues resulting from condensation. This work had to be completed with the added complication of keeping the facility open.

  Anyone involved in the design of indoor swimming pools or investigating condensation related issues with a swimming pool should read Joseph W. Lstiburek’s very accessible Building Science Insight which is an edited version of the insight that first appeared in the ASHRAE Journal.

  “The problem is fundamentally pretty straightforward. We have a huge internal moisture load that, for once, you cannot blame on your mechanical engineer or HVAC contractor. There’s a pool filled with water in your building for Pete’s sake. You can’t dehumidify your way out of the problem; you can’t ventilate your way out of the problem. You can localize the problem by  depressurizing the pool area relative to adjacent spaces or by pressurizing a boundary space between the pool area and adjacent areas, but, in the pool area, you are pretty much toast.” 

  “We need to be perfect. And the only wall that will work, of course, is “the perfect wall.” We have been here before. Put the water control layer, the air control layer, the vapor control layer and the thermal control layer on the outside of the structure.  Put everything else inside, especially the services. Same for the roof. Done.”

  “A few little tricks of the trade – think of cladding as a dehumidifier that sucks moisture out of the shaded stuff. That means the back of the cladding will get wet if there is a flaw in your wall. What are the odds of there being a flaw or less than perfect workmanship?  If  I  were  using wood cladding, I would not just back ventilate it, I would back-coat it with primer and paint. Just like the old guys used to. I do not want the wood to absorb water.  If it does, it can leach tannins and other water-soluble extractives. Ask me how I know?” 

  “If it is cement siding, you had better coat it on the backside, as well as ventilate it. If you have brick, you had better ventilate the heck out of the space.”

  “If it is metal, you had better think a lot about stainless steel and magic pookey to protect it, as well as good cladding ventilation. If there is a flaw and air gets out, the air is going to be carrying more than just water vapor: chlorine, bromine and other aggressive oxidizing (a.k.a. corrosive) agents. You ever see what they put into the water? It will eat your insides out and the insides of your wall assembly as well.”

  Useful links Insight: In the Deep End, Joseph W. Lstiburek, Ph.D., P.Eng., Fellow ASHRAE http://www.buildingscience.com/documents/insights/bsi-055-in-the-deep end/files/BSI-055_In_the_Deep_End_rev.pdf $1m legal tab in pool fight, North Shore Times, 15th Nov 2011 http://north-shore-times.whereilive.com.au/news/story/1m-legal-tab-in-pool-fight/ Collingwood pool shut over roof crash fear, Melbourne Leader,  2nd March 2010 http://melbourne-leader.whereilive.com.au/news/story/collingwood-pool-shut-over-roof-crash-fear/ Case Studies Australian Institute of Sports Aquatic Training & Testing Centre (Built 1984) Roof refurbishment 2010 http://www.proctorgroup.com.au/australian-institute-of-sport-aquatic-centre/ Australian Institute of Sport Aquatic Training & Testing Centre (Built 2008) http://www.proctorgroup.com.au/australian-institute-of-sports/ Products Proctor Roofshield – Unique air permeable breather membranes offering the highest vapour permeability of any construction membrane available globally http://www.proctorgroup.com.au/roofshield/ Dow Styrofoam – High performance closed cell rigid insulation board with good resistance to rain, snow, frost and water vapour which makes it an exceptionally stable material, retaining its initial insulation performance and physical integrity in swimming pool applications over the very long term http://www.proctorgroup.com.au/styrofoam/ Proctor Profoil – Specialist vapour barrier with a 40 year warranty in swimming pool applications http://www.proctorgroup.com.au/proctorprofoil/

  
  

  
  

   

   

   

   
• The Tom Cruise Wall - High Risk Walls by Andy Russell
  in Condensation, Global Building Envelope Practices
  17 Oct 2011  | 0 Comments

  Not in reference to Top Gun, but the1983 film “Risky Business,” building science guru Joseph Lstiburek in his own inimitable style has this month published his latest Building Science Insight entitled “Risky Business : High Risk Walls.” For anyone designing buildings that incorporate tilt-up concrete walls, particularly in the colder and temperate climate zones of Australia, and plan to insulate on the inside of the panel, this very readable paper is well worth taking a look at. Unfortunately we have seen first hand this winter, such walls going badly wrong and suspect there will be more out there. Below is an extract from the edited version of this insight which first appeared in the ASHRAE Journal. "As my friend Mac Pierce likes to point out: you could get a blindfolded drunk epileptic to cross Niagara Falls on a high wire without a net, but it wouldn’t be a good idea. There are some wall assemblies that are like that. One in particular irritates me. It has lead to a great deal of grief. It has problems that can easily be avoided. But simple analysis shows it works, and that is the rub. The simple analysis shows that it works, but the real world shows that it does not. It gets better. More complicated analysis shows that it sometimes works, and truth be told, the real world shows that it also sometimes works. No moisture and exceptional workmanship can make it work. What are the odds? Clint Eastwood thermodynamics again: do you feel lucky punk? Well, do you? So what does this wall look like? I am not sure what to call it. It has a face-sealed cladding (“perfect barrier”) that is impermeable to water vapor. It is insulated on the interior with air permeable insulation usually held in place between steel studs or impaled on pins protruding from the back of the cladding and covered by a vapor barrier. Let’s call it a “Tom Cruise Wall.” The insulation is typically a fiberglass batt “smushed” between steel studs. Sometimes, it is rockwool or mineral wool pinned to the interior of the exterior cladding. The fiberglass batt sometimes comes with a foil facing – the “vapor barrier.” More often the whole kit and kaboodle is covered with sheet polyethylene that may, or may not, be called an “air-vapor barrier.” Yuck. So what is the problem? Well, the cladding is easy to make almost perfectly airtight and the interior lining is almost impossible to make airtight. That’s it? Really? That simple? Yup. You’re kidding. Everyone knows you can’t seal plastic sheets on the inside of wall assemblies and make them airtight."  The full paper is available from www.buildingscience.com or directly by downloading here

   

   
• ABCB Handbook on Condensation in Buildings now available for download by Andy Russell
  in Condensation
  22 Jul 2011  | 5 Comments

  The ABCB Condensation Handook Released In partnership with the Australian Institute of Architects and industry, the ABCB has produced a Non-Mandatory Handbook to provide greater clarification for managing condensation in buildings. It was a privilege to work over the past year with the entire group that undertook on the challenge of writing this handbook. The ABCB and Australian Institute of Architects really do have to be commended for taking the initiative to put this together. I hope that this will reduce the number of condensation related problems in new build and existing buildings being upgraded to improve the energy efficiency of Austalia's commercial and residential building stock.  Here is what the ABCB say about the handbook.  This Non-Mandatory Handbook is intended to assist architects, designers and builders in the assessment and the management of the risk of condensation and its consequences in the contemporary industry environment and should be read in conjunction with the BCA provisions relating to Damp and Weather Proofing, and Energy Efficiency in all classes of buildings. Appropriate detailing of buildings ensures they remain serviceable, the occupants remain healthy and that the design life of the building is not compromised.  The outcome of failing to adequately detail for moisture control is a common underlying cause of many reported building failures.  The rectification of the side-effects of condensation can result in costly repairs and in the case of related fungal and mould infestations, prohibitively expensive repairs.   Traditionally our buildings were not airtight and had little or no insulation.  However, as a result of changing occupant practices and the introduction of mandatory energy efficiency requirements, building practices are changing, requiring a change in detailing so that moisture related problems are adequately managed.   While a common cause of moisture related problems is due to water ingress, the focus of this Handbook is controlling moisture within the building’s fabric resulting from condensation. Handbook is available for free download here.

   
• Australian Institute of Architects 'Refuel' 2011 National Seminar Series Dates announced by Andy Russell
  in Condensation, Seminars & Events
  12 Jul 2011  | 5 Comments

  As part of Australian Institute of Architects (AIA) 2011 Refuel National Seminar Series I will be presenting around the country during August and September. Full details are available on the AIA website here   Leaks & Seals: Avoiding condensation through smart design We all know how important it is to keep rain out of buildings but if it is sealed up too tight how do we stop it getting wet from the inside?  The drive for energy efficient buildings with improved air tightness and insulation, and efforts to seal up the building, changes the dynamics of the building envelope but a building still needs to breathe. Through a combination of case studies and sound technical information, this seminar, considers how the building envelope needs to deal with water in its various forms and how considered design and detailing can minimise and prevent damage. Confirmed dates are listed below.

  Location	Date	Time
  Hobart	Wednesday 3rd August	12:30pm - 2:30pm
  Launceston	Thursday 4th August	10:00am - 12:00pm
  Melbourne	Monday 8th August	6:00pm  - 8:00pm
  Canberra	Monday 29th August	9:00am - 11:00am
  Sydney	Thursday 8th September	9:00am - 11:00am
  Darwin	Wednesday 14th September	9:00am - 11:00am
  Brisbane	Thursday 15th September	6:00pm - 8:00pm
  Newcastle	Thursday 22nd September	6:00pm - 8:00pm
  Perth	Monday 26th September	5:30pm - 7:30pm
  Adelaide	Tuesday 27th September	5:30pm - 7:30pm
  Cairns	Tuesday 25th October	12:00pm - 2:00pm
  Townsville	Wednesday 26th October	12:00pm - 2:00pm
  Rockhampton	Thursday 27th October	12:00pm - 2:00pm
  Toowoomba	Monday 31st October	12:00pm - 2:00pm
  Gold Coast	Wednesday 2nd November	12:00pm - 2:00pm

   

  To register for Leaks & Seals: Avoiding condensation through smart design in your local state or territory
  please go to the AIA website  click here.
• Condensation Season by Andy Russell
  in Condensation
  17 May 2011  | 1 Comment

  Around this time of year we start to hear stories about leaking roofs or “rain in the roof ” even though there have been no clouds in sky for several days. These so called “ghost leaks” and tales of rotting out or corrosion of bottom plates are in fact often a result of the building getting wet from the inside. A generation of new buildings in most other temperate climates of Europe, North America,Japan and New Zealand have been through a cycle of moisture related problems closely correlated to changes away from more traditional designs, to new construction with higher levels of thermal insulation and air tightness. Although well intentioned, the failure to consider the building envelope holistically created problems by trapping moisture in the structure. Most methods designed to keep the rain and wind out, involve wrapping the building in impermeable materials such as foil, steel, glass or other waterproofing materials. Such materials do a great job of stopping the water from getting in, but they also prevent vapour from getting out safely. In the winter, these materials in the roof space or your wall cavities can get wet due to condensation. If there is condensation on the inside of the windows during the winter then there is a good chance that condensation is also forming unseen on the inside of walls or roof spaces that have been wrapped in foil. If insulation is not installed correctly in relation to the position of vapour barriers and breather membranes, mistakes can lead to structural damage and health problems for occupants caused by mould springing up and spreading unnoticed within the roof space and walls, resulting in expensive rectification. If the foil sarking should not be used on the cold outside of insulation then what can be used to wrap the building. The product you will be using goes under the generic name of ‘breathable membranes’. A breathable membrane on the cold side of the insulation does much the same job as conventional sarking such as keeping rain, snow and dust from getting into the roof space and wall cavities, but also lets the moist air escape. Typically breather membranes are textile products that work much in the same was as Gortex fabric and have a very low vapour resistance of less than 0.26MNs/g. These should not be confused with some perforated foil type products labelled as “breathable”, despite having a vapour resistance more than10 to 70 times the breathable membrane standards overseas. To allow condensate to drain safely out of the wall to help wall assemblies dry out, common practice overseas is to have avented cavity between the external cladding and the breather membrane. This concept is increasingly being adopted by good builders in Australia. As we go into winter has anyone seen an increase in condensation, mould or damp issues that can't be explained by leaks?
• Sustainable Building: does it measure up? by Andy Russell
  in Sustainability, Condensation, Seminars & Events
  11 May 2011  | 1 Comment

  Looking forward to the Association of Building Sustainability Assessors (ABSA) from 19 - 20 May 2011 at the Melbourne Convention and Exhibition Centre.  The 2-day conference will examine the tools, processes and products enhancing sustainability and will be putting measurement under the microscope. Some of the headline speakers include The Hon Mark Dreyfus QC MP, Parliamentary Secretary for Climate Change - What's on the horizon for energy efficiency? Adam Bandt MP, Federal Member for Melbourne, Australian Greens, A Sustainable Future – What do we need to do? Sam Mostyn, Director, Institute for Sustainable Solutions, University of Sydney - What are the sustainable solutions – is private practice a solution? Tone Wheeler, Director, Environa Studio - The third wave of sustainability Conference website is here... We also have a display booth and I am presenting one of the workshops on Friday afternoon on the subject of controlling condensation.  “Controlling Condensation in Buildings, and the forthcoming ABCB Condensation Handbook” The drive for energy efficient buildings is leading to improved levels of air tightness and insulation, thus creating a greater differential between the interior and exterior environments. Failure to consider the building envelope holistically had resulted in an increase in the number and severity of condensation problems as some common design practices contradict basic laws of building physics. ABSA members are uniquely placed to pick up on potential issues at the design stage and ensure that our buildings do not suffer the condensation problems experienced overseas and increasing in all climates of Australia. Later this year, the ABCB will publish a condensation handbook highlighting the dangers associated with condensation and measures to minimise the risk of future problems. This presentation through the use of case studies, theory and experience illustrates what is going wrong and how it can be avoided with a just a basic understanding of the functions, performance and appropriate detailing of different types of sarking, insulation and ventilation.