r\t~ktbilding Official

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1 Design, Environment & Construction 2635 Talley Street P.O. Box 220 Decatur, Georgia Fax MEMORANDUM February 28, 2018 TO: Cc: From: RE: Peggy Merriss, City Manager David Junger, John Maximuk, Angela Threadgill r\t~ktbilding Official Amendment to certification program requirements in Unified Development Ordinance Section High Performance Building Standards The purpose of this memorandum is to recommend an amendment to Article 10, Section 1.6(A) 2 of the Unified Development Ordinance regarding conformance with the High Performance Building Standards for new single family residential and residential substantial improvements. The High Performance Building Standards were adopted by the City Commission in November of 2014 conditioned that the City of Decatur and required the use of three certification programs: Earthcraft, LEED for Homes, and 2012 National Green Building Standard-Silver. Both Earthcraft and National Green Building standard have recently updated their certification programs to enhance building performance. In particular, the newly adopted 2015 National Green Building Standard has raised program certification requirements to a position that Design Environment and Construction Division believes that a bronze level certification is equivalent to Earth craft base certification. LEED for homes, which has never been used in the City of Decatur since the ordinance was adopted, has not modified their standard and remains an equivalent, or slightly higher standard than the other two programs. In order to best evaluate the programs against the current ordinance standards, the Design Environment and Construction Division hired Mr. Carl Seville of SK Collaborative, Decatur, GA to provide an independent audit of the National Green Building Standard and Earthcraft programs. The goal of the audit was to provide a comparison document that establishes equivalency and to ensure that both revised programs were increasing their performance standards compared to earlier versions. Mr. Seville confirmed that the programs do increase building performance requirements from previous versions, and provided the recommendation that the National Green Building standard set to should be changed to the 2015 version and any level of certification under this program be considered an acceptable equivalent to the other programs. A copy of Mr. Seville's report is attached to this memorandum. This memorandum also clarifies the Earthcraft standards that allow for the use of Earthcraft "Renovation" and National Green Building Standard "Renovation" for qualifying substantial improvement renovation projects. These two standards are specifically designed for renovations while the "house" certifications are for new single family homes and are not interchangeable. The proposed amendment to the text is as follows: An Equal Opportunity Employer

2 City of Decatur 2. High Performance Building Certification All buildings subject to this paragraph must comply with one of the following: a. Any level of Certification usin&: the current version of the National Green Buildin&: Standard (ICC 700) for new homes or renovations b. Any level of certification using the current version of LEED for Homes; or c. Any level of certification using the current version of the Earth Craft House, Earth craft Renovation or the Earth Craft Sustainable Preservation program If approved, the effective date for these requirements will be the date of adoption by the City Commission. Property owners will be permitted to register for either the 2012 or 2015 versions of the National Green Building Standard until June 20, 2018 as there is a 1 year concurrency period in effect. An Equal Opportunity Employer

3 EarthCraft House and NGBS 2015 Program Comparison This document was prepared for the City of Decatur to evaluate the common residential green building certification programs that comply with the High Performance Building Ordinance requirements for new homes and major renovations. EarthCraft House and the National Green Building Standard (NGBS) are the main programs that builders use to comply with the Decatur High Performance Bu ilding Ordinance. LEED for Homes is another option, however few, if any, builders certify to this program. EarthCraft house was created in 1999 by Southface Energy Institute and the Greater Atlanta Homebuilders to certify homes. The program has expanded to include multifamily buildings, renovations, commercial and historic buildings and communities. The program is managed and administered by Southface. NGBS evolved from the National Association of Homebuilders Green Building Guidelines, having developed into an ANSI and I ECC standard. The program certifies single and multifamily housing, both new construction and renovation as well as communities. The program is managed and administered by Home Innovation Research Labs. The current version of the ordinance requires EarthCraft certification at any level, and a minimum of NGBS Silver. Both programs are undergoing version updates. Southface recently released an updated worksheet for EarthCraft House new construction that will apply to all homes registered for certification after January 1, The version will be required for all homes (new and renovation) registered after June 20, The updated programs in general increase building performance requirements for certification. A comparison of new EarthCraft House and programs is listed in table below. The first comparison is for new construction, followed by renovation. The recently updated EarthCraft House new construction is essentially pass/fail- a project must meet all applicable requirements to certify with no points or optional items for base level certification. There are additional "badges" for high performance, indoor air quality, comfort, and health which are optional and roughly equate to higher levels of certification. The is similar to previous versions with a set of specific mandatory requirements, plus both minimum point requirements in each section plus a minimum total score for each level of certification. For the comparison below, a worksheet was completed for a typical new home that meets minimum high performance building citification levels under {Bronze level) and the new EarthCraft House program. Please let us know if there are any questions or if any additional information is needed. Submitted Carl Seville SK Collaborative, LLC

4 New Construction Program Comparison The table below lists the individual sections on the EarthCraft House worksheet on the left and equivalent Chapters on the right. Program requirements (i.e. mandatory items) and optional items are listed for each. Note that as the sections do not align completely, several NGBS chapters spread across multiple EarthCraft sections. EarthCraft House (all items below required) Site Planning: No Invasive Plants, Tree Protection Resource Efficiency: Stud spacing, header size, advanced framing, energy heel trusses, engineered trim Durability & Moisture Management: Foundation requirements, crawlspace and slab vapor barrier required, wall weather barrier and flashing required, no vapor retarders in walls. No site grading requirement. Lot Design, Preparation & Development: No Mandatory Requirements: Achieve a minimum of 50 points, options include location, site management Resource Efficiency: No Mandatory Requirements: Achieve a minimum of 42 points, Penalty for homes over 4000 SF, Options include recycled waste, recycled content, regional, or bio-based materials, Resource Efficiency (combined with above): Mandatory: Foundation requirements for habitable space below grade, crawlspace and slab vapor barrier required, weather barrier and code flashing, grading away from foundation. Options for sealed crawl, window flashing optional but necessary to capture adequate points.

5 High Performance Building Envelope: 5 ACH 50, meet 2015 IECC {proposed GA amendments), Grade 2 insulation, knee walls to R-18, U.35, SHGC.27 glazing, R-5 attic hatches Energy Efficiency: Mandatory: meet 2015 IECC including 3 ACH 50, 2015 IECC (national) includes R-20 or Rl3+R5 continuous walls, Grade 1 insulation, U.35, SHGC.25 glazing, R-38 attic hatches. UA Equivalent through ResCheck also meets requirements. Achieve a minimum of 30 points through meeting above requirements. High Efficiency HVAC Systems: Manual J and S, 90% Furnaces, 14.5 SEER AC, Sealed Ductwork with Mastic or Mastic Tape, filter access sealed, 6% total duct leakage required for all ducts, 3% outside duct leakage if ducts in unconditioned space Indoor Air Quality: Whole house ventilation verified, ENERGY STAR bath fans verified, Kitchen exhaust verified, Radon vent system, No unvented combustion heaters, fireplace with glass doors, Low VOC finishes, trim, cabinets. Energy Efficiency: Mandatory: Manual J, Sand D, Sealed Ductwork (UL Tape OK), 4% total leakage required for ducts in unconditioned space No duct testing required if ducts in conditioned space, Indoor Environmental Quality: Mandatory: whole house ventilation, verified per COD, Bath fans, Radon vent system, no unvented combustion heaters. Kitchen exhaust optional Achieve a minimum of 25 points ~---~- Plumbing & Irrigation: Water heater efficiency, hot water pipe insulation, WaterSense plumbing fixtures required (1 shower head exempted) Efficient Lighting & Appliances: 90% High efficacy lighting, ENERGY STAR appliances required Water Efficiency: Mandatory: Irrigation system requires WaterSense or equivalent design professiona I Achieve a minimum of 25 points. Equivalent to WaterSense fixtures required to meet point threshold. Energy Efficiency: ---l-m_ andatory: 75% High efficacy lighti_n=g_, 1 ENERGY STAR appliances optional Education & Operations: Owners manual, certified ECH Builder, and marketing are required. Operations, Maintenance and Building Owner Education: Mandatory: Operations manuals and training

6 Using the table above and the worksheet prepared to meet Bronze level certification, we believe EarthCraft House and Bronze level certification are reasonably equivalent programs. In some cases, EarthCraft is more rigorous and in others NGBS is more demanding. Areas where NGBS is more rigorous: Earth Craft Minimum Grade 2 Insulation Minimum Grade!Insulation Minimum R-13 Wall Insulation Minimum R-20 (orr 13 + R5 Continuous) Manual J and 5 Manual J, S, and D Maximum U-0.35, SGHC-0.27 Glazing Maximum U-0.35, SHGC-0.25 Glazing Maximum 6% Total duct leakage Maximum 4% Total duct leakage Maximum 5 ACH50 Envelope Leakage Maximum 3 ACHSO Envelope Leakage Areas where EarthCraft is more rigorous: EarthCraft Advanced Framing Minimum 90% Furnaces, 14.5 SEER AC WaterSense Plumbing Fixtures Minimum 90% High efficacy lighting 75% High efficacy lighting Kitchen and Bath exhaust flow verified Total duct leakage t esting required if HVAC in conditioned space ENERGY STAR Appliances Renovation Program Comparison NGBS requires any renovation project to retain a minimum of 50% of structural systems and foundation remain in place. Project of larger scope must use new construction program. NGBS Bronze renovation certification requires a minimum of 15% energy efficiency and 20% water efficiency improvement from existing conditions, meeting mandatory items in all categories, and meeting a minimum number of points {88 for Bronze level certification). Energy efficiency calculations are generally determined through before and after HERS ratings, water efficiency through a calculator on the worksheet {~ rt-rg a.f.t-r:ehe-v-a-t.fe retttl i Fe5-rA -et -~e fi -a-a<:i-a-te r- 't-ea'ls-f9+l:l5-a--ati-a~ m t:tff'l-flttm &er-e r points, the total required based on conditioned area at completion. Optional points are available for preparing before and after HERS ratings. The EarthCraft renovation program was last updated in An update is expected in 2018 which will affect this comparison. For the comparison below, a worksheet for the current EarthCraft Renovation and Renovation programs was completed for a typical Decatur home.

7 Program Sections for Renovation EarthCraft Renovation Site Planning: Required: no invasive plants, erosion control plan, site assessment required. Points available for transit, proximity to services, cycling tracks, tree preservation. Renovation Lot Design, Preparation & Development: No mandatory items, points available for similar items to EarthCraft, plus stormwater management, pervious paving, light concrete. Waste Management: No required items. Points available for recycling construction waste and salvage for reuse. Resource Efficiency: Points available for building reuse, salvaged materials, recycling construction waste. Resource Efficiency: Required: minimum stud spacing and limited framing at windows and doors required. Points available for advanced framing, engineered materials, recycled content materials Durability and Moisture Management: Required: weather barrier, window and door flashing, crawlspace vapor barrier, tile backer board, slab gravel required. Points available for sealed crawlspace, siding, roofing, and window warranty, foundation drains, dehumidification. Indoor Air Quality: Required: no unvented combustion appliances, furnace sealed or isolated from living space, fireplaces have outside air, lead paint test required. Points available for fireplace doors, HVAC filters over MERV 6, low VOC finishes, duct protection, no carpet, asbestos test. High Performance Building Envelope: Required: Air sealing and insulation to IECC 2010, seal boots and fans to drywall, attic knee walls to R-18, U.S, SHGC.30 required. Points available for blower door test, Resource Efficiency (combined with above): Points available for universal design, product declarations, prefabricated components, stacked stories, prefinished materials, etc. Resource Efficiency (combined with above): Mandatory: foundation damp proofing, crawlspace vapor barrier, weather barrier, standard flashing, tile backer, sloped horizontal ledgers, grade away from house. Points available for enhanced foundation waterproofing, sealed crawlspace, moisture content sampling, window flashing, covered exterior doors. Indoor Environmental Quality: Mandatory: no unvented combustion appliances, air sealing to garage, lead testing, bathroom ventilation, radon venting required. Points available for no fireplace, sealed combustion equipment, low VOC finishes, ventilation verification, duct protection, ducts in conditioned space, Energy Efficiency: Mandatory: 2015 IECC insulation and air sealing, grade 1 insulation, 75% high efficacy lighting, U.35, SHGC.25 glazing, and

8 additional air sealing, higher insulation levels, sealed crawlspace, grade 1 insulation, insulated corners and headers, spray applied insulation, higher efficiency windows, radiant barrier roof decking. Energy Efficient Systems: Required: Manual J and S, no electric resistance heat, seal ducts with mastic, duct insulation, max duct leakage to outside 6%, outside air ventilation, and 50% high efficacy lighting required. Points available for high efficiency HVAC, ducts in conditioned space, improved duct leakage, ENERGY STAR exhaust fans, verified flow rates, efficient water heaters, ENERGY STAR appliances. Water Efficiency: Required: low flow fixtures, required. Points available for replacing existing high flow fixtures, ENERGY STAR clothes washer, lower flow fixtures, hot water system design. Education and Operations: Required: Owners Manual Points available for recycling center, composting bin, EarthCraft HVAC contractor, program marketing. minimum 15% overall energy efficiency improvement required. No optional points. Energy Efficiency (Combined with Above): Mandatory: Manual J, Sand D, Sealed Ductwork (UL Tape OK}, No duct testing required if ducts in conditioned space. No optional points. Water Efficiency: Mandatory minimum 20% water efficiency improvement required using indoor and outdoor calculations. No optional points. Operations, Maintenance and Building Owner Education: Mandatory: owners manual and occupant training Using the table above and comparing completed renovation worksheets for EarthCraft Renovation and the Bronze level renovation certification, we believe EarthCraft Renovation and are reasonably equivalent programs. In some cases, EarthCraft is more rigorous and in others NGBS is more demanding.

9 Earth Craft No Minimum 2 Insulation Grade Manual J and S Insulation required to meet 2010 IECC No minimum energy efficiency requirement No minimum water efficiency requirement No radon venting required Areas where NGBS is more rigorous: Minimum Grade 11nsulation Manual J, 5, and D Insulation required to meet 2015 IECC Min. 15% energy efficiency improvement Min 20% water efficiency improvement Radon venting required unless house tests below limits Areas where EarthCraft is more rigorous: EarthCraft WaterSense Plumbing Fixtures Total duct leakage testing required if HVAC in conditioned space ENERGY STAR Appliances Reduce air infiltration by 20% or 7ach50 Conclusion Using the table above and the program worksheets prepared for each, we believe Bronze level certification is at least equal to, if not more rigorous than the current EarthCraft renovation program. File attachments for reference: "Decatur N~w Example": Excel file with sample new home certification to bronze level "EarthCraft House New Construction Worksheet": Excel file listing all EarthCraft new home requirements "Decatuer Remodel Example": Excel file with sample renovation certification to bronze level "EarthCraft Renovation Decatur Example" : Excel file with sample renovation certification

About Southface. Southface promotes sustainable homes, workplaces and communities through education, research, advocacy and technical assistance.

About Southface. Southface promotes sustainable homes, workplaces and communities through education, research, advocacy and technical assistance. About Southface Southface promotes sustainable homes, workplaces and communities through education, research, advocacy and technical assistance. 1 Photo: Jonathan Hillyer, 2009 2 Green Building Services