The Definition of interior/exterior in the LOW-EMITTING MATERIALS credit is a bit confusing for me. What is exaclty defined as a waterproofing membrane or air- and water-resistive barrier materials?
In Europe we usually have walls made of bricks or concrete, where an insulation system is applied on top (outdoor). What kind of products should I count as exterior and interior? Is the brick/concrete wall itself the air- and water -resistive barrier, so everything that is applied on top of the wall is a exterior product, and everything that is faced indoors is considered as a indoor product?
We just need to know this because we have to decide for which of our products we have to make emission test.
Thank you.
Joanna Switzer
Sustainability Project ManagerAtkins
59 thumbs up
February 17, 2017 - 4:29 pm
In my past experience, based on LEEDv3 &v2 protocol, the exterior weatherproofing membrane includes all products that are critical to keeping moisture from entering the building or damaging interior wall and floor substrates. Therefore, in addition to the structural and exterior finish materials (brick/concrete), this COULD include waterproofing coatings or plastic sheeting ("vapor barrier") & associated sealants/caulks applied inside the exterior wall cavity to serve as an additional precaution. This may not be as common in mass/solid wall construction - more common in layered/ framed assemblies.
Reinhard Oppl
Independent consultant on VOC issuesformerly with Eurofins Product Testing A/S
329 thumbs up
February 18, 2017 - 7:27 am
I remember from my time with EQ TAG at US GBC that we used the terms weatherproofing system or waterproofing membrane to identify the limit between the inside and the outside, where we believed that some materials would not influence the emissions into indoor air (such as facades or within-facade thermal insulation), as just described by Joanna. If you have another building structure than you may consider another layer in the wall as the barrier between materials with or without impact on indoor air. Waterproofing membranes used in the inside, in kitchens or in bathrooms etc., surely are considered interior materials.
Michelle Halle Stern
Senior Sustainability ConsultantGreenwood Consulting Group
121 thumbs up
February 19, 2017 - 12:49 am
There are several wall section drawings in the reference guide to help with the distinction. The image for a masonry wall shows the dividing line between the sheathing and the interior batt insulation.