This is a legitimate question, worthy of further debate.
The concern: "The proposed credit introduces a layer of complexity that will likely discourage project teams from pursuing it. Instead of simply telling you what standard a product should follow it is asking you to do complex calculations."
The proposed credit primarily adds complexity in two ways:
1. Combines previously separate credits into a single credit worth up to five points, allowing partial credit for partial compliance.
2. Uses surface area to determine the percentage of compliance for all materials except furniture, which uses a cost basis.
Project teams must identify the total area for flooring/ceilings, walls, and insulation, and the area with compliant materials. Compliance for each layer is required. Projects must identify the cost of compliant furniture and total furniture cost. Previously, teams only had to identify that materials used in a project were compliant (and fewer materials were involved).
What are the benefits of this additional complexity?
Flexibility –Projects gain incentive to pursue low-emitting materials in all areas, as partial credit from one system (e.g. flooring) can be combined with partial credit in another (e.g. furniture) to achieve points. Previously the credits were all-or-nothing; therefore, teams could be discouraged from pursuing the points at all. In addition, this flexibility provides a platform for USGBC to easily adjust the stringency of the requirements without modifying the underlying structure as the market and technology change.
More Protective of Occupants –Larger surface areas of products have greater potential emissions. Products may emit VOCs through layers. By requiring all layers of floors, walls, and ceilings to comply and by basing the credit calculation on surface area, the credit requirements likely will correlate better with actual VOC exposure levels resulting from product emissions.
A cold read of the bare bones credit language may seem intimidating (change can be scary and little explanation is provided). However, we plan a simple spreadsheet to perform the calculations. See the example spreadsheet linked under “New Information Required” on the Birds Eye View tab. The reference guide will also contain guiding examples and other education materials.
How could we make the credit simpler?
Basing partial credit on cost instead of surface area would be simpler but cost is not necessarily tied to the potential emissions in the building. Eliminating the option of partial credit completely would greatly simplify the credit but make it tougher to achieve. Eliminating the content requirements on paints, coatings, and full-spread adhesives to instead only require emissions would be simpler but would eliminate an option for partial compliance and could arguably remove some protection for occupants.
Do these benefits warrant teams providing surface areas?
What other ideas would make the credit simpler?
Reinhard Oppl
Independent consultant on VOC issuesformerly with Eurofins Product Testing A/S
329 thumbs up
December 20, 2010 - 4:07 am
For full disclosure, I am Director VOC Testing at Eurofins Product Testing A/S, the largest world-wide provider of VOC emissions chamber testing, member of European standardization body CEN TC351 WG2 on VOC testing, and of several task forces dealing with this issue.
I see the newly proposed systems approach as a huge progress because it regulates the surfaces that really are in a building, instead of singular products. As an example, today it is acceptable to use low VOC emissions wood flooring together with glue and surface coating with low VOC content, but still showing high VOC emissions. The new approach will be much more consistent in this sense.
The formulas used for this pilot credit are indeed typical engineer work, engineers are happy with calculation formulas while several other actors on the field may be discouraged using these. Here we may need to use more simple language. An idea is to say: At least 80% of each system (e.g. floor) shall be made of only low VOC emitting material for getting partial credit, and each system shall contribute 25% of total credit points. We need to discuss this in EQ TAG of US GBC.
Another issue is the limitation to only very few individual VOCs emissions limit values, which do not include quite many other VOCs emissions that may occur. The easiest solution of this critical issue would be to work with a Total VOC (TVOC) limit of e.g. 500 µg/m³ after 14 days - not because TVOC is a health relevant parameter, but because TVOC is a good and easy to handle surrogate for having very long lists of limit values for individual VOCs.
Let's make it good but simple.
Josh Jacobs
Technical Information & Public Affairs ManagerUL Environment
515 thumbs up
December 20, 2010 - 1:53 pm
As another member of the LEED IEQ TAG, we are grateful that you are open to working on making the credit better. We think that it is great that the first draft tried to address more products and bring true product emission limits to more products in the indoor environment, but we must come up with an easier way for people to understand the credit. We also have an opportunity to produce a leadership credit/requirement, not something that doesn’t meet code.
In the proposed LEED for Homes it simply states that a product must meet CA 01350 for flooring and insulation. This could work for each product/layer named in the new credit and coupled with your 80% of each system might be very helpful in easing the confusion factor. I would suggest that the limit be above 85% though as that is what is currently written in to the International Green Construction Code and ASHRAE 189.1 requires all products be low-emitting (although Paints/Coatings & Adhesives/Sealants can still get through with just content limits). These are meant to be code – the baseline for sustainable buildings – the LEED Rating System should require a step-up.
We have been advocating that a Total Volatile Organic Chemical measure be put in place for this credit for years. EQ 4.5 (Furniture) has always had this 500 µg/m³ TVOC limit and in fact is still going to be held to that in the proposed credit. Why shouldn’t other products be held to this precautionary measure in our sustainable buildings?