Tom O´Leary interview: Covering the basics of complex issues of Passive Houses

Watch Tom O´Leary and Heide Gentner catching up at the North American Passive House Network Conference in New York after meeting in Darmstadt Germany, at the International Passive House Conference in 2016. Tom O´Leary, Founder of the Passive House Academy, was a speaker at the conference and hosted a workshop on multi-family buildings. The sold-out, intense session on how to achieve multi-family Passive Houses focused mainly on the tricky issues such as basements, ventilation systems, elevators, and trash shoots.

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Visit from New York: first impressions of the pro clima headquarters

John Druelinger of 475 High Performance Building Supply is visiting the pro clima headquarters in Schwetzingen, Germany for the first time. In the video he talks about his first impressions, why he is working with pro clima, and how 475 excites people.

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Juan Levy on the advantages of being a Passive House Designer

Juan Levy, Passive House Designer and Founder and President of FutureFitBuilding LLC based in Philadelphia, PA, spoke with Heide Gentner of pro clima TV at the North American Passive House Network Conference. Please watch the above video to find out why Juan Levy became a certified Passive House Designer and whether designing a Passive House is difficult or not.

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Ken Levenson on Passive House Standard – pro clima TV interview

Ken Levenson is a registered architect in New York State and the President of NY Passive House, a nonprofit dedicated to promote the Passive House Standard as well as a founding member of the North American Passive House Network. In recent months, New York City passed a law mandating that city owned buildings, which are being contructed have Passive House Standard as an optional goal to fulfill energy efficiency requirement. This optional goal which will move to a mandatory fullfilment in the future. In his interview with pro clima´s Heide Gentner, Levenson said “Passive House is a critical tool to establish a carbon free society and answer the climate crisis that we are facing”.

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pro clima presents a new super adhesive for building envelopes: ORCON MULTIBOND

pro clima presents a new super adhesive for building envelopes – Even at temperatures below zero degrees Celsius: The ORCON MULTIBOND joint adhesive provides extremely high adhesive strength immediately

The new joint adhesive from a roll for interior and exterior use: ORCON MULTIBOND

It sticks immediately to mineral subsurfaces, and even temperatures below zero Celsius on the building site are no problem: the new ORCON MULTIBOND joint adhesive supports installation technicians in implementing joints quickly, cleanly and reliably to achieve a sealed building envelope. This adhesive tape, which is applied from a roll, features pro clima’s patented SOLID adhesive technology. Continue reading

Air-tight building – why it is important

Protection from mould and heat loss

The air­proof­ing lay­er pro­tects the in­su­la­tion from mois­ture and con­dens­a­tion from the in­side, en­sures that the in­su­la­tion works ef­fect­ively and provides a healthy in­door liv­ing en­vir­on­ment.

The thermal in­su­la­tion sep­ar­ates the in­door from the out­door cli­mate. The tem­per­at­ure dif­fer­ence between the two cli­mates at­tempts to be­come equal­ised through the flow of air. This means in winter the warm air from the build­ing trans­fers through the struc­tur­al ele­ments to the out­side. The air­proof­ing lay­er pre­vents this air flow, the so-called con­vec­tion, and there­fore the loss of hot air to the out­side. The in­teri­or space is here not her­met­ic­ally sealed off – like us­ing a plastic bag – from the out­side air. In­stead, the ex­change of air from the in­side to the out­side con­tin­ues via dif­fu­sion.

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John Druelinger – pro clima TV interview at the NAPHN 2016

John Druelinger of 475 High Performance Building Supply spoke with pro clima´s Heide Gentner at the North American Passive House Conference 2016 in New York City about retrofits and renovations in the North East United States. Airtight sealing is an important topic for Druelinger who is an avid blogger. He uses twitter and facebook to spread the word about airsealing and supports the movement to increase energy use, comfort, and health for the buildings´ occupants.

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Adhesive tape – how it works

pro clima clients ask – pro clima engineers answer

Adhesion in the area of airtightness and windtightness involves sticking parts together in a strong, permanent manner that would not stick together without the aid of adhesives. These adhesive joints should last as long as the building component itself! As well as offering high adhesive strength, these adhesive joints must also be able to accommodate typical movements in building components in line with the requirements of DIN 4108-7. The surface finish and so-called surface tension both have a decisive influence on the quality of adhesion. In order to stick materials to one another, adhesives are used that stick firmly to the subsurface (adhesion) and, at the same time, have sufficient internal strength (cohesion).

Various forces are at work in adhesive joints: cohesion, which holds the adhesive itself together, and adhesion, which holds the adhesive to the subsurface.

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Flank diffusion – what it is and how to prevent it

pro clima clients ask – pro clima engineers answer

Airtightness is good, but it is not everything: there is also the matter of diffusion! When we speak of diffusion in civil engineering, we are referring to the gradual transport of moisture through a building component. This transport is driven by the pressure difference between the interior and exterior. As water molecules always want to move from warm environments into the cold, diffusion normally occurs from the inside to the outside in wintertime. A vapour retarder hinders the transport of these molecules.

Unforeseen: Entry of moisture through adjacent components

For example, if an interior wall penetrates through an insulation layer (the vapour retarder is cleanly attached to the wall on the left and right, i.e. everything is airtight), so-called flank diffusion can occur. The water vapour looks for the path of least resistance – which in this case is the interior wall. In the case of structures that are open to diffusion on the outside, this may represent a manageable risk. However, if the structure is impermeable to diffusion on the outside, moisture problems can soon occur. After all, there is a fundamental problem here. The interior wall has a large surface area, so it absorbs a lot of moisture, but there is only a smaller area available for drying to the inside – i.e. the wall cap.

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Tom O’Leary: That´s why you should build a passive house

Tom O’Leary built Ireland´s first certified Passive House. During the 20th International Passive House Conference in Darmstadt, Germany, O’Leary spoke with pro clima TV´s Heide Gentner at the pro clima booth. Watch the video above to learn more about Tom O’Leary´s motivation to build a passive house as well as his quest to spread passive house awareness.

For more information on the 21st International Passive House Conference in Vienna, Austria in 2017 please visit: