NY Passive House (NYPH) Meetup: New York City Message Board › Thermal Bridging – the Next Building Envelope Frontier
New York, NY
With unanimous agreement on the requirement for excellent insulation and growing understanding of the benefits of airtightness, the next frontier to address in terms of energy efficiency is without question thermal bridging.
This ubiquitous energy parasite has up to now been blissfully ignored by most building professionals, but it is high time that we develop an understanding of how thermal bridges occur, what adverse effects they have on our buildings and, most importantly, how we can eliminate them through clever detailing.
A thermal bridge occurs typically when there is a change in the building envelope in terms of insulation thickness (at junctions where there are different R-values), most commonly found at the wall-junction eave, for example, but also around window frames and at floor to wall connections. Thermal bridges not only result in significant energy losses (as much as 7,000 kBtu (or 2,000 kWh) per year for a modest single family home), but also reduce surface temperatures which can lead to (a) radiant temperature asymmetry or the sensation of a draft and (b) more critically, excellent conditions for the growth of mold. Thermal bridges thus increase energy consumption, reduce thermal comfort and can create a health risk.
But all is not lost. There are very simple ways of designing-out thermal bridges through well informed detailing and using software such as Therm (a freeware) as well as Excel-based Psi calculators. Those interested in Passive House will be especially aware of the need for "thermal bridge-free" design (defined by the Passivhaus Institut as < 0.01 W/mk), but how can you be sure that your details really are in fact thermal bridge free?
There’s no shortcut here – you just have to calculate them. At the Passive House Academy we have been training Architects and Engineers how to design and calculate thermal bridges for the past 18 months. Once equipped with this knowledge, you can save your Client money on their heating bills, improve their comfort and well being and keep ahead of the curve in terms of service offerings. You’ll no longer sigh at the prospect of calculating Psi values (apologies for the deliberate pun!), but relish the experience of making far superior buildings.
The next AIA Accredited course on Thermal Bridging in NYC in association with the New York Passive House group is on April 15th and 16th
Click on the link for more details and to reserve your place-
Let’s make happy buildings.
Tomas O'Leary Passive House Academy