The new Integrative Process credit in LEED v4 asks design teams to explore energy- and water- related improvements early in design. Moreover, it asks teams to use energy modeling to explore synergies and impacts across building systems — to perform holistic investigations rather than the sort of targeted, credit-specific calculations that have come to characterize other LEED credits. Here’s a breakdown of the requirements and how you can achieve them.
To support high-performance, cost-effective project outcomes through an early analysis of the interrelationships among systems.
The credit requires both early-stage “discovery” analysis and later-stage “implementation” steps for both energy- and water-related systems. The “discovery” phase involves investigating at least two energy-related and several water-related sustainable design strategies prior to the end of schematic design.
Energy-related investigations can include:
▪ Site conditions, such as assessing shading from surrounding buildings
▪ Massing and orientation, and their impacts on HVAC loads, energy use, and renewable energy
▪ Envelope attributes, such as insulation levels, glazing ratios, and shading
▪ Thermal comfort ranges, including expanding the comfort zone
▪ Plug and process load reductions
▪ Programmatic and operational settings, such as schedules, occupancy, and required square footage
Water-related investigations include:
▪ Assessing indoor and outdoor water demand
▪ Assessing process water demand, such as laundry, kitchen, and other equipment demand
▪ Assessing non-potable supply sources, including rainwater capture and graywater
The Sefaira Solution
Sefaira’s one-click whole building energy and water analysis, combined with its built-in Concept Comparison and Strategies & Bundles framework, make integrated early-stage investigations fast and painless. Here are five examples of early-stage investigations taken directly from IP102 (using a multi-family residential project in Denver, Colorado):
1. Impact of massing on energy use & HVAC loads
We uploaded three design options, then created a Concept Comparison. We can immediately see that the best option (Massing 3: Corner) has 14% lower energy use, 25% lower peak heating loads, and 23% lower peak cooling loads compared to the worst option (Massing 2: Tower).
2. Impact of varying insulation
We created several strategies to look at adjusting insulation values for walls, roof, and glazing. Improving all three would lead to a total energy reduction of 15%, and could reduce both heating and cooling capacity. (For a quick tutorial on creating strategies and bundles, check out this video.)
3. Impact of adding shading
We created shading strategies for each facade. (Rather than guess at the right shading lengths, we used Response Curves to find optimal values for each facade. That’s not required by LEED, but it’s easy to do and adds a level of rigor to the analysis.) Good shading can reduce total energy use by 6%, and reduce cooling capacity by a significant 28%.
(Bonus investigation: Because it’s so easy, we combined shading and insulation strategies to see what impact it would have — even though that’s not required by LEED. The results: dramatic reductions in both heating AND cooling capacity — meaning better performance, with less expensive mechanical systems.)
4. Preliminary assessment of indoor water demand
We set up our water use baseline in accordance with LEED WE-102, then ran an analysis. We can see that the building is using 1.4 million gallons of water. We can also see that water heating is responsible for 12% of our annual energy consumption. (We could easily create strategies to test different water use reduction measures, such as efficient fixtures.)
5. Assessment of potential graywater supply
We investigated using graywater from faucets, showers, and clothes wathers to supply water closets. This could allow graywater to supply 15% of the building’s annual water use.
These studies can be done quickly, using SketchUp or Revit models as a basis — making it easy to achieve LEED IP102. Sefaira’s analysis can help architects achieve other LEED credits as well — see the full credit breakdown in our article on LEED v4.
More examples of early-stage analysis are covered in our three-part series on Performance Based Design:
Part I: Making the Most of Pre-Design
Part II: Creating High-Performing Concepts
Part III: Executing the Vision