The credit language reads: Design at least 50% of interior nonstructural walls, ceilings, and floors to be movable or demountable
What classifies a ceiling as a demountable ceiling? Would this only include ceiling clouds? Or does this also include an Armstrong ACT, for example, where the tiles can be taken down and reused? Or does the grid it sits in NOT make it demountable? Secondly, can open ceilings be considered demountable? Part of the demountable goal is flexibility, and open ceiling provide total flexibility, so in a floor plate where there is 50% open ceilings, and 50% ACT, it's hard to define the line between what is demountable and not
Tristan Roberts
RepresentativeVermont House of Representatives
LEEDuser Expert
11474 thumbs up
May 19, 2020 - 12:37 pm
As LEED does not appear to have a specific, rigorous definition for a demountable ceiling (I only found a definition in the glossary for partitions), it seems to me that you have latitude to make a common-sense interpretation. I would consider a ceiling tile system demountable (or movable -- another key term), even if there is a grid component that may not be movable. It seems reasonable to assume that even in a movable system, not 100% of components are movable.
I would have a harder time calling an open ceiling movable. It seems that the term is meant to apply more to partitions and tiles. There are other aspects of the credit requirements that appear more applicable, i.e. plug-and-play lighting control and power systems. I think you would have a stronger case applying those requirements to open portions of the ceiling.
Brian Kish
Senior ArchitectAE7
May 19, 2020 - 3:02 pm
Tristan, thank you so much for your quick response.
In such case, do you think we could exclude open ceiling from our calculations since by definition it cannot be demountable or fixed due to the lack of any applied materials? Instead we would just take the total of demountable ceiling surfaces and divide it by the the total area of non-demountable (e.i. gypsum) surfaces?
Thank you in advance!
Tristan Roberts
RepresentativeVermont House of Representatives
LEEDuser Expert
11474 thumbs up
May 19, 2020 - 4:40 pm
No, I don't think that approach makes sense in terms of how the credit requirements are written.
You said that the border between the two areas is a little fuzzy -- can you justify a 50% calculation?
Then I would apply the other strategies to get to the total of three.
I would also note that GBCI would be the final arbiter on whether an open ceiling would fall within the intent of what they mean as movable or demountable. I don't think it fits the definition, but perhaps they would allow it intent-wise. I would ask if that is your pathway to earn the credit.
Agata Mozer
3 thumbs up
January 19, 2022 - 11:09 am
Hi Brian, did you get any feedback from GBCI regarding the open ceiling?