2009 Seattle Energy Code Impacts: See below for a recap of Changes in Envelope performance from 2006 to 2009

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1 2009 Seattle Energy Code Impacts: Building Envelope Impacts: Below is a Summary of Changes that impact building envelope construction planned for 624 Yale. There are several modifications are required to comply with the 2009 Seattle Codes Seattle Energy Code Impacts: See below for a recap of Changes in Envelope performance from 2006 to Seattle Energy Code Changes for Non-Residential Projects Envelope Component 2006 Seattle Energy Code 2009 Seattle Energy Code Code Glazing Percentage (Window-to-Wall Ratio=WWR) 45% 40% Glazing U-Value Glazing Solar Heat Gain Coeff Glazing Visible Light Transmittance Opaque Wall (metal studs) R-value R-13 + R-7.5 rigid c.i. R-13 + R-10 rigid c.i. Opaque Wall (mass) R-value R-13 + R-7.5 rigid c.i. R-13 + R-10 rigid c.i. Floor R-value (mass) R-30 R-30 Roof R-value (insulation above) R-30 R-38 Color Legend for Table Above No Change from 2006 SEC Increase in Code Stringency Review of Envelope Compliance for 624 Yale o Envelope performance planned in 2008 for the 624 Yale Building does NOT comply with the 2009 Seattle Energy Code (SEC) requirements without modifications o Additionally, the performance of the envelope planned in 2008 had a safety factor that was above the minimum required. This was recommend in case there were permit corrections that were received from the Seattle DPD. o Most projects that Rushing has submitted under the 2009 SEC have a minimal safety factor for envelope compliance and have not needed to change envelope assemblies from what were planned at the time of permit submission. o Based on reviewing the envelope the following improvements in the envelope assemblies are recommended by Rushing/NBBJ: Upgrading the Glazing Performance to meet 2009 SEC default minimum performance values Upgrading the Roof Insulation These upgrades provide enough improvement in the envelope performance to comply with the 2009 SEC requirements of 17

2 Building Envelope Impacts: 2009 Seattle Energy Code Impacts, continued: Table showing impact of Envelope Improvements and Compliance Margin 624 Yale ENVSTD Summary Envelope Component Code Building (points) ENVSTD Output for Compliance under 2006 SEC Proposed Building (points) Points above Code % Above Code ENVSTD Compliance under 2006 SEC % ENVSTD Complance under 2009 SEC with Glazing Upgrade % ENVSTD Compliace under 2009 SEC with Glazing Upgrade & Roof Upgrade % Description of Glazing Performance Upgrade recommended for 2009 SEC Compliance o Glazing assumptions from 2008 permit set for 2006 SEC Compliance U-Value = 0.40 SHGC = 0.38 VT = 0.60 o Glazing requirements for 2009 SEC Compliance U-Value = 0.38 SHGC = 0.35 VT = 0.60 o Additionally, refer to Seattle DPD CAM 403 for information required for permit submission that requires NFRC simulations for the basis of design glazing at permit intake. ENVSTD Output for Compliance under 2009 SEC with Glazing Upgrade of 17

3 Building Envelope Impacts: 2009 Seattle Energy Code Impacts, continued: Description of Roof Performance Upgrades recommended for 2009 SEC Compliance o Increase roof insulation by 1 ENVSTD Output for Compliance under 2006 SEC with Glazing Upgrade & Roof Upgrade Other Envelope Performance Assumptions to Recap o Glazing is assumed to remain as fixed glazing. There were no operable windows planned for 624 Yale due to acoustical concerns with proximity to I-5 and Mercer Interchange with I-5. Adding operable windows (U=0.45, ~18% higher than code default) would require further changes to the envelope components and may trigger energy modeling (RS-29) to comply with 2009 SEC code provisions. o West Façade Glazing and Vertical Fin Elements NFRC rating of the glazing for U-Value thermal performance will need to be carefully reviewed with the glazing manufacturer. There may be benefits to reducing the depth of the fins as this may reduce the size of the support brackets which may result in a better thermal performance for the glazing. The size of the vertical fin cannot be modeled in ENVSTD therefore reducing (and therefore shading from the fins) does not impact the shading assumptions in ENVSTD. o Stairwell skylight to remain as this provides a daylighting credit. If skylight is removed this reduces the daylighting potential of the building and reduced the proposed building ENVSTD points by ~200 points. Building therefore would not comply without further envelope upgrades above and beyond what was considered for glazing and roof upgrades. o Wall insulation values remain the same as planned in 2008 o Floor insulation values remain the same as planned in 2008 o See Attachments for the Revised Envelope Compliance Calculations and Assumptions Update Details for Wall Insulation o The details for the wall insulation may want to be updated to include the use of a thermally broken clip system for supporting the exterior cladding through the continuous rigid insulation. o Since, 2008 there are new systems available that may be beneficial to utilize for this project. Such as fiberglass clips for installing the exterior cladding through the rigid insulation of 17

4 Building Envelope Impacts: 2009 Seattle Energy Code Impacts, continued: New requirements for Continuous Air Barrier and Building Air Leakage Testing o Section has new requirements for a continuous air barrier. Per discussions with NBBJ the project had already made provisions for having a continuous air barrier that is already documented well on the Permit Drawing set from Only minor modifications to the drawings would be required to comply with 2009 SEC requirements. No construction cost impacts are anticipated. o Section outlines the requirements for air leakage testing prior to Certificate of Occupancy for the building. These are new requirements in the 2009 SEC. Building to be sealed to have an air leakage of less than 0.40 CFM per SF of building envelope area at a pressure of 0.30 w.g. Option #1: Inspect During Construction, Test, & Report essentially if you do the inspections during constructions the building then you don t have pass the test. Only the results of the test are required to be reported to the city. Option #2: Pass the Test essentially if you decide to follow this test you must test and if you fail then you reseal the building until you can pass the test. The inspections and air leakage testing will have cost impacts that will need to be included in the project construction budget of 17

5 Building Envelope Impacts: 2009 Seattle Energy Code Impacts, continued: of 17

6 Building Envelope Impacts: 2009 Seattle Energy Code Impacts, continued: of 17

7 2009 Seattle Energy Code Impacts, continued: Mechanical System Impacts: Mechanical System Impacts: 2009 Seattle Energy Code Impacts: Increase Cooling Efficiency required at Main Rooftop Air Conditioning Units o Per discussion with Johnson-Barrow (Energy Labs local vendor) the estimated cost to upgrade would be an additional 5-10% of the unit first cost from This is on the order of $40,000 to $70, Seattle Energy Code Table 14-1A: 2006 Seattle Energy Code Table 14-1A: of 17

8 Mechanical System Impacts: 2009 Seattle Energy Code Impacts, continued, Airside Economizer Requirements changes will impact Tenant Improvement Options o The allowable amount of the airside non-economizer cooling capacity was restricted in the 2009 SEC to 20 tons (240,000 BTUH) or 10% of the building economizer capacity per the changes in Exception 9 of Section o This impacts the plan for 24/7 cooling without airside economizer for the building. o During the design of the 624 Yale project there were many discussions regarding alternate means for achieving airside economizer at the future tenant server rooms. Among these ideas were a dedicated outside air shaft, floor-by-floor outside air intake louvers, etc. None of these ideas were incorporated into the final design. o The project was planning on providing a condenser water riser with space coordination for a future fluid cooler on the roof to allow for 24/7 cooling via high-efficiency watercooled air conditioning units per Option 9a of Section 1433 Exception 9. o Non-Economizer Cooling Sizing for the fluid cooler and piping was as follows: 6.5 Floors 15 tons per floor of 24/7 cooling Planned: 97.5 tons of 24/7 cooling without airside economizer o Per 2009 Seattle Energy Code the tonnage of non-economizer cooling would be limited as follows by Exception 9 of 1433: 320 tons of cooling with airside economizer at ACU-1-R-1 and ACU-1-R-2 10% of 320 tons = 32 tons Available 32 tons of 24/7 cooling without airside economizer o Therefore, a new plan would be required to provide the same amount of future 24/7 cooling without airside economizer that was planned for Possible options: Floor-by-Floor Outside Air Intake and/or Exhaust Louvers Outside Air Intake and/or Exhaust Shafts Dedicated future rooftop units for 24/7 cooling o The other item to note is that the plan for the building may be very different depending on whether the building is marketed as a single tenant or multi-tenant office building: Multi-Tenant need for 24/7 cooling through all floors of the building is more likely Single Tenant Major server rooms can be located closer to the roof where it is more feasible to accommodate airside economizer from rooftop package units. Then the 30+ ton non-economizer allowance can be used on the lower floors of the building for smaller spot cooling loads. o Rushing recommends waiting until a tenant is found and then building the infrastructure for 24/7 cooling airside economizer as required into the tenant permit. This is a good plan as long as the building does not plan to move forward as a speculative office building of 17

9 Mechanical System Impacts: 2009 Seattle Energy Code Impacts, continued, 2009 Seattle Energy Code Section 1433 Exception 9: 2006 Seattle Energy Code Section 1433 Exception 9: of 17

10 Mechanical System Impacts: 2009 Seattle Energy Code Impacts, continued, o As a side note: Per ASHRAE airside economizer for cooling in Seattle s Climate is 64% more efficiency than cooling without airside economizer. Chapter 12 Energy Metering Natural Gas Sub-metering will have a minor impact of Tenant Improvements for Retail Kitchen Tenants o For a restaurant tenant sub-metering would only be required if they were utilizing the natural gas for both HVAC loads (heating) and Process Loads (cooking). Most likely the gas service would only be used for cooking as the plan is for the HVAC to have electric heat of 17

11 2009 Seattle Energy Code Impacts, continued: Electrical System Impacts: Electrical System Impacts: Below is a Summary of Changes that impact Electrical Systems planned for 624 Yale. Depending on how the electrical contractor and consultant want to redesign the system there are some pretty major changes to the electric one-line to comply with the 2009 Seattle Energy Code Seattle Energy Code Impacts: Lighting Allowances (w/sf) o Office Reduced to 0.90 w/sf from 0.95 w/sf. This will impact tenant lighting design marginally. Lighting Controls o Parking garage lighting is required to have occupancy controls o Lighting within the daylight zone is required to have primary and secondary daylight zone controls o Emergency egress is required to have controls to turn off when the building is not occupied. New Requirement for Energy Metering per Chapter 12 o Electrical riser design will be impacted to provide the ability to sub-meter the following uses within the building per Chapter 12: HVAC System Energy Lighting System Energy Plug Load System Energy Process Load System Energy (non anticipated) Misc Energy (domestic hot water & elevators) o Additionally an energy metering data acquisition system is required that has the following capabilities: Store 36 months of data Show daily, monthly, and annual energy consumption data Have permanent display for the building engineer Display shall show: the current energy demand for the whole building, updated for each energy source, as well as the average and peak demands for the previous day and the same day the previous year, and the total energy usage for the previous 12 months. o There are several ways to accomplish the new electrical sub-metering requirements. One of these is to provide an electrical panel for each of the sub-metering uses above. Each electrical panel can then be sub-metered accordingly. Panels can contain embedded meters or separate meters can be utilized of 17

12 Electrical System Impacts: 2009 Seattle Energy Code Impacts, continued, o New Requirement for Energy Metering per Chapter 12 Typical Office Floor Electrical Riser Diagram Planned per Permit drawing Electrical One-Line on E1.01: (drawings by Sequoyah Electric and Lane Coburn & Associates, LLC) Possible Revised Typical Office Floor Electrical One Line Riser Diagram: Typical office floor sub-metering calculations to gather end-use data by data acquisition system: o HVAC System Energy = Lighting Energy Plug Energy o Lighting System Energy (dedicated sub-meter) o Plug Load System Energy (dedicated sub-meters) of 17

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14 2009 Seattle Energy Code Impacts, continued: Renewable Energy Impacts: Renewable Energy Impacts: Below is a Summary of Changes required by the 2009 Seattle Energy Code Chapter 16 and Seattle DPD Director s Rule Per the 2009 SEC an onsite renewable energy is required. As an alternate per Director s Rule Renewable Energy Credits (REC s) can be purchased. o Based on the Gross Conditioned Space Footage for 624 Yale the approximate cost for the REC s purchase would be $22,000 to $25,000. The cost depends on the energy sector that the client wants to purchase the REC s from. o This is a much more cost effective than putting renewable energy on the site. Per the Director s Rule the REC s should be purchased prior to permit submission Seattle Energy Code Chapter 16 On-site Renewable Energy Systems On-site Renewable Energy vs Renewable Energy Credit Purchase Manual Input Auto Calculated Gross conditioned floor area: 191,750 SF Required On-site Renewable Energy: 500 BTU/SF Annual onsite production: 95,875 k-btu Onsite Solar Photovoltaic Renewable Energy Credit Purchase Total area of PV collectors: 1,871 SF Required REC's Purchase (kwh/sf): 125 kwh/sf System Rated Output 29.0 kw Required REC's Purchase: 23,969 kwh Approximate Total System Cost: $ 202,779 Cost of REC's/kWh $ $/kwh Typical panel footprint (angled at 47.5 ): 14 SF Approximate Total Cost of REC's $ 22,531 Number of panels: kwh/sf required Post July 1, 2012 Notes: 2009 Seattle Energy Code Chapter 16 requires on-site renewable energy systems for all new buildings and all additions of more than 5,000 square feet to existing buildings Seattle Energy Code Section 1621 requires annual energy production of 500 BTU/SF of gross conditioned floor area Seattle Energy Code Director's Rule alternate requires REC's Purchase 125 kwh/sf of gross conditioned floor area of 17

15 Renewable Energy Impacts: 2009 Seattle Energy Code Impacts, continued, of 17

16 Renewable Energy Impacts: 2009 Seattle Energy Code Impacts, continued, of 17

17 2009 Seattle Mechanical & Plumbing Code Impacts: Below is a Summary of Changes that impact Mechanical and Plumbing Systems planned for 624 Yale. Overall only minor modifications are required to comply with the 2009 Seattle Codes Seattle Mechanical Code Impacts: Access panels for cleanout of Type 1 Grease Exhaust Ductwork are required at every level o Minor cost impact to provide an access panel on each floor. Clearance around Type 1 Grease Exhaust Ductwork o Clearance changed to 6 clearance minimum (from 3 ). Shaft coordinated for 624 Yale was slightly oversized and has minimum required clearance for 2009 code. No impact Seattle Plumbing Code Impacts: Requirement that all domestic cold and hot water valves meet NSF-61 requirements. o Minor cost impact to upgrade valves to meet NSF-61 requirements of 17