M D, have you looked over the examples posted in the Doc Toolkit above? Maybe seeing some sample calcs will help clear this up more easily than an explanation.

Thanks for your prompt reply Tristan.

I have taken a look but I am not sure what completed design areaCompleted design area is the total area of finished ceilings, floors, full-height walls and demountable partitions, interior doors, and built-in case goods in the completed project. It does not include exterior windows and doors. refers to. In the examples I have seen, all the completed design areas are equal or smaller than the prior condition areas. So I am assuming it is any area that has been changed? Then, the retained components area would be the difference between the prior condition area and the completed design area? It is a tad confusing..

Correct, the completed design areaCompleted design area is the total area of finished ceilings, floors, full-height walls and demountable partitions, interior doors, and built-in case goods in the completed project. It does not include exterior windows and doors. is the area that has been changed or altered from prior condition, however the uploaded calculator is confusing. It seems that it is calculating the completed designed area as opposed to the retained area.

Thanks April!

1 -So, as I mentioned before, the retained components area would be the difference between the prior condition area and the completed design areaCompleted design area is the total area of finished ceilings, floors, full-height walls and demountable partitions, interior doors, and built-in case goods in the completed project. It does not include exterior windows and doors.?

2-For a material that hasn't changed, we would put 0 under completed design area, right?

M D, your baseline for savings should be all the interior elements, so you need to measure more than just the one.

Thanks Tristan,

So how many of them is a good number? Or should I list all?
The project has only reused 100% of finished ceiling but no other components as the space was completely empty when the tenants moved in. So can only the ceiling be listed to achieve the credit? Or do we need to include all other components and just input 0 square feet for reuse?

M D, see the third Design Development item under Checklists on the above tab.

Yes, this is what is meant by the credit language because it is about the non-structural wall as a component, despite whether you re-paint or refinish the wall. The floor coverings are the non-structural element of the floor, which is why they talk specifically about floor coverings as opposed to the sub floor. Hope this helps!

One side for windows.

In my opinion, this should qualify, especially given the credit language's use of the word "systems."

Shirong, the key thing we are looking at in this credit is the surface area of walls, etc.. So you can include party walls insofar as you are including the surface area of the wall that is within the tenant spaceTenant space is the area within the LEED project boundary. For more information on what can and must be in the LEED project boundary see the Minimum Program Requirements (MPRs) and LEED 2009 MPR Supplemental Guidance. Note: tenant space is the same as project space..

Lauren, did you submit and get a ruling on these issues? I am particularly curious about the refinished concrete.

Lauren and Tristan,

Our project is similar - we retained all concrete and either refinished it or covered it with new carpet (we diverted/recycled the old carpet). When we submitted this, we said that 100% of our "finished flooring" was retained (referring to the concrete)....however, the review came back with issues pending: (1) "Please revise the form to include all new and retained floors in the Completed Design AreaCompleted design area is the total area of finished ceilings, floors, full-height walls and demountable partitions, interior doors, and built-in case goods in the completed project. It does not include exterior windows and doors., and include in the Retained Components Area only the floors that were in the space both prior to construction and in the completed design." So....does this mean that we need to include the total sf of the new carpet that we installed in the “completed design area” for “finished flooring”, even though this area covers some of the same area as the retained concrete? If we do this, then the “completed design area” will be more than the “retained components area”...correct?

Gail, it seems to me that including concrete that is covered with carpeting as a "retained" surface is not the intent of the credit or the calculation method, that could be what's throwing you off.

I would agree with Tristan. For this credit they are interested in seeing the non-structural elements retained, therefore, if you covered the concrete with new carpet, that area would be considered new. The concrete would be considered structural. As for the brick walls in Lauren's case, I believe the refinished "structure as finish" situation would count as a retained element, even with new stain/paint. Same with the concrete floor - because you did not recover the floor with new floor coverings, this area could be considered as retained, despite the new polish/stain. Curious to hear if Lauren received a review ruling though!

I've seen the same information. Here's what LEED HC says: "Hazardous materials that are remediated as part of the project scope shall be excluded from the calculation of the percentage maintained." CIRCredit Interpretation Ruling. Used by design team members experiencing difficulties in the application of a LEED prerequisite or credit to a project. Typically, difficulties arise when specific issues are not directly addressed by LEED information/guide/LI 5583 from 8/2002 also allows you to exclude from MRc2 calcs. Have you searched the Reference Guide addenda?

Thanks Susan. That's my sense too. I've looked through some of the addenda but may have missed it?

I did a quick search through the new LEED Interpretations and did not find it either. But the search should have popped up the LEED HC item and did not. Clearly I need more search practice.

Trying to bring this back into the forum discsusion again. Anyone know where I can reference as verification that my approach is acceptable?

Guidance from the GBCI confirming this approach:

“Although it is not specifically stated in any reference guide, addenda, or LEED InterpretationLEED Interpretations are official answers to technical inquiries about implementing LEED on a project. They help people understand how their projects can meet LEED requirements and provide clarity on existing options. LEED Interpretations are to be used by any project certifying under an applicable rating system. All project teams are required to adhere to all LEED Interpretations posted before their registration date. This also applies to other addenda. Adherence to rulings posted after a project registers is optional, but strongly encouraged. LEED Interpretations are published in a searchable database at usgbc.org. (CIRCredit Interpretation Ruling. Used by design team members experiencing difficulties in the application of a LEED prerequisite or credit to a project. Typically, difficulties arise when specific issues are not directly addressed by LEED information/guide) for MRc1.2 in ID+C or BD+C, GBCI confirms that projects should exclude the hazardous materials completely from the calculation for this CI credit – both numerator and denominator. This is assumed through the guidance found in MRc1.1 (pg. 347 in the BD+C reference guide) which states, "Hazardous materials that are remediated as a part of the project must be excluded from the calculation of the percentage maintained," even though it is technically a separate but related credit. Also, it is discussed through LI# 5885 from 9/19/2005, even though this is not directly applicable to 2009 projects or CI projects at this time.”

Hooray! Official closure. Thanks for posting this.

Sara, I think that the intent would be to count the part not covered by carpet.

I have a question with similar facts.

In our project, all of the flooring system will remain but all of the carpeting will be replaced with new carpets. I guess this means that the entire floor area does NOT count as retained?

Also, all of the drop ceiling system will remain but the current fluorescent lighting system will have some changes made to it. The reflective shields may be reused but the ballasts and fixtures will be replaced since the fluorescent bulbs will be changed to more efficient ones, i.e. T12 to T8 or T5 (will have to confirm). Does this mean that the entire ceiling area WOULD count as retained?

And only a small number of non-bearing walls will be removed.

Would this project be eligible for 0 points, 1 point, 2 points? Any tips would be appreciated.

Gail, I agree that existing credits do not cover this, with the possible exception of MRc2. It has been a conscious choice for LEED not to cover mechanicals in this way, so I am doubtful that it would be allowed as an ID credit.

James, the guidance in the LEED Reference Guide, page 224, seems pretty clear—determine the finished area, like a painter. This is similar to the guidance for LEED-NC, which says to use visible surface area. It seems like you'll get a lot of surface area out of this.... too good to be true? But I would proceed in that fashion.

There was a credit interpretation about demountable partitions (EQc3.2, 12/1/07) that states, "Full height, demountable modular walls are essentially the same in form and function as permanent wals and as such are not considered funiture...Please note that such modular walls potentially affect other LEED credits (such as daylighting and views) and should therefore be included in any calculations and submissions required for those credits as well."

Caveats? Twofold - first this was a NC CIRCredit Interpretation Ruling. Used by design team members experiencing difficulties in the application of a LEED prerequisite or credit to a project. Typically, difficulties arise when specific issues are not directly addressed by LEED information/guide, so I am not sure how it applies to CI. Secondly, USGBC has indicated that they are not bound by LEED v2 CIRs in LEED v3.

Leslie,
Page 225 of the CI reference guide might explain why this is happening, but the rationale is a bit confusing.

In the % reuse calculation, the "Total Retained Components Area (sf)" is the numerator. The denominator is *either* the "Prior Condition Area (sf)" OR the "Completed Design AreaCompleted design area is the total area of finished ceilings, floors, full-height walls and demountable partitions, interior doors, and built-in case goods in the completed project. It does not include exterior windows and doors. (SF)" depending on which is larger. (All areas are surface areas)

Say, in one scenario, you retain 900 sf of the existing 1000 sf of interior walls. You'd think your reuse would be 90%. But if you now build an additional 1000 sf of new interior walls, say for additional offices or conference rooms your reuse percentage goes down to 45%. That's not what I expected either.

The Ref. Guide states:
"By using the larger of the 2 values in the denominator, this equation puts projects that have minimized materials use in the completed design on a level playing field with projects that have optimized reuse of components from the prior condition."

Thus, projects that have optimized reuse of existing components only get credit for that if they *also* minimize materials in the completed design. The more materials are used in the completed design, the more your percentage of reuse will go down.

The credit requirements state: "Maintain at least 40% or 60% of the existing non-shell, non structural components (e.g., walls, flooring and ceiling systems. The minimum percentage interior component reuse for each point threshold is as follows: Interior Reuse: 40%, 1 point, 60%, 2 points."

I think many of us have interpreted "40% or 60% of existing" to mean we only look at the percent retained of the existing "Prior Condition Area," regardless of how much material surface area is in the final completed design. The requirements here don't say "have 40% or 60% of the Completed Design Area material area consist of Retained Components."

It's worth noting that in CI v2.0 Reference Guide the credit requirements and calculations for this credit are defined essentially the same as they are in CI 2009. And in NC 2.2, for credit 1.3 it says to "use existing interior non-structural elements in at least 50% of the completed building," which is what we're finding this credit to be pushing us toward. So there is a precedent for the credit working this way.

The credit intent is to "conserve resources, reduce waste and reduce environmental impacts of new buildings as they relate to materials manufacturing and transport." So maybe it's appropriate for a project that both reuses interior components AND adds little new material to score higher than a similar project that reuses the same amount of existing materials, but uses more total materials. But since I can't think of other credits where we earn points for using less material overall is than if we use more materials, it doesn't seem fair to hold back points for doing so only on those projects that are pursuing the building reuse credit.

Thank you David. This really helps explain the intent and clarifies what I should be calculating. I like the fact that they are rewarding reduced use of additional materials, I just had no idea that's what this credit was about until I read through the calculations in detail.

On the one hand, this may not be seen as the primary intent of this credit, since during the initial build-out of a core and shell building there are not usually any existing tenant improvements (walls, ceilings, etc) to maintain.

On the other hand you might argue that it can be attained in some cases where there are non-structural elements provided by the landlord such as ceiling grids, corridor and core walls, etc, that the tenant is using as-is instead of demolishing or altering them.

Might be a judgement call! Another example of a time when it's good to have a few extra points more than your certification goal in case the reviewer sees it differently.

The one thing that you can usually count on with LEED credits, is following the intent of the credit. You definitely cannot earn the credit if there are zero non-shell, non-structural components. If it is a new CS building, it is highly unlikely that there would be sufficient interior elements to pass the "good faith" test of whether the credit is applicable to the project.

That is my feeling as well, but it would be could if someone could quantifiably "draw the line"...if someone from USGBC could put in a minimum % of area required to qualify (similar to LEED NC MRc1.2).

Right now I would say minimum 50% as in LEED NC...then I'm safe, but that's a bit harsh for a CS developement wanting to certify later spaces under CI.

Hi Jean,
After some more digging in the reference guide, I think I may need to reverse my answer a bit. An example is given in the ref guide "If the ceiling is exposed, both prior to construction and in the final design, include this area". This makes me think that it does not matter what is there to begin with, what matters is whether or not you retain it. If it is an exposed concrete floor at construction, and the project team retains that- then it counts. My apologies on the first response, that was wrong. Based on my re-reading, this project is eligible for a core and shell building, it would just need to retain that existing finish.

What parameters would you set for the objects to create the schedule?