E-1 C15-2022-0042 PRESENTATION — original pdf

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2212 Trailside-proposed single family home located in the Zilker neighborhood BOA Case # C15-2022-0042 Technical, tree, fire and taps are all approved Zoning has rejected the proposed plan on the grounds that the Habitable Attic, with a 7’ finished ceiling, does not meet the criteria for exempting the area from Gross Floor Area (GFA). We believe 2212 Trailside as designed with the br4/office habitable attic area wedged into a space that would typically be a non-habitable attic meets the GFA exemption and the staff application of 3.3.4 is incorrect because 1. The proposed Habitable Attic does not have any external walls (3.3.4.a) 2. 100% of the proposed exempted space has a CEILING HEIGHT of less than 7’ (3.3.4.b- measured to the bottom of the horizontal member of the roof truss refers to HEIGHT and not CEILING HEIGHT) therefore satisfying the ratio requirement E-1/1-PRESENTATIONThe GFA Exemption Pathway under discussion 3.3.4 Does not apply to this situation. You can exempt GFA from McMansion via 3 pathways: 3.3.2 for Parking Areas 3.3.3 for Porches Basements & Attics 3.3.4 for areas < 5’ in HEIGHT This approach is using 3.3.3(C) for the Habitable Attic. 3.3.3(C) has 6 criteria to qualify as a habitable attic exemption (Must meet all 6) 1) The roof above it is not a flat or mansard roof and has a slope of 3:12 or greater 2) Fully contained within the roof structure 3) It has only 1 floor 4) It does not extend beyond footprint of floors below 5) It is the highest habitable portion of this section of the building & adds no mass to structure AND 6) 50% or more of the area has a CEILING HEIGHT of seven feet or less E-1/2-PRESENTATIONThe Area of Bedroom 4/office has a max ceiling height of 7’ in order to allow the hvac ducting to access the room from the mechanical above. The ceiling structure is designed with a truss in order to provide stability needed to support the roof over the egress skylights. This section is at the highest portion of the roof showing the complete truss. As the roof slopes down to the rear wall the trusses will change configuration and get smaller. The Habitable attic is all within the roof area of the second floor and does not penetrate the tent or add mass to the structure The skylights are operational and provide egress for the space. E-1/3-PRESENTATIONCEILING HEIGHT CEILING HEIGHT are key words for this exclusion and it is important to understand the full context…. The City of Austin has adopted the 2021 IRC R202 defines CEILING HEIGHT as “The clear vertical distance from the finished floor to the finished ceiling” ▪ ▪ stands CEILING HEIGHT is not defined under 25-1-21 nor under Subchapter F and thus, the IRC definition The Case of Mistaken Identity- 3.3.4’s HEIGHT is not the same as 3.3.3’s CEILING HEIGHT For years, the wording of an entirely separate and distinct GFA exemption has tripped up anyone who has tried to understand Austin’s inordinately confusing code. Section 3.3.4 has a very specific intent in that it allows you to exempt spaces with a HEIGHT (not the same as CEILING HEIGHT) of 5’ or less. E-1/4-PRESENTATION3.3.4. An enclosed area shall be excluded from the calculation of gross floor area if it is five feet or less in height. For purposes of this subsection: Area is measured on the outside surface of the exterior walls; and Height is measured from the finished floor elevation, up to either: the underside of the roof rafters; or A. B. 1. 2. the bottom of the top chord of the roof truss, but not to collar ties, ceiling joists, or any type of furred-down ceiling. Must meet both A&B in order to be excluded from GFA This project is not trying to claim the 3.3.4 exemption. That could/should be the end of the story except, folks get tripped up on the wording in 3.3.4 that states Height is measured from the finished floor elevation, up to either (1) the underside of the roof rafters or (2) the bottom of the top chord of the roof truss, but not to collar ties, ceiling joists, or any type of furred-down ceiling. The main intent of 3.3.4 is to change the the GFA exclusion height definition from 25-1-21 (46) for GFA. 25-1-21(46) defines GFA as anything with a clear height of 6 ’or more 3.3.4 is in place to change what is captured under GFA to anything greater than 5 ’in height or more. 3.3.4(B) further elaborates on how one measures this to stop folks circumventing GFA calculations by artificially furring down a ceiling to below 5 ’so it does not count for McMansion GFA. That’s it. 3.3.3 also has a very specific intent, one completely independent of 3.3.4 3.3.3 is specific to "ceiling height" Please read 3.3.4 again - It states "An enclosed area shall be excluded from the calculation of gross floor area if it is 5’ or less in height” There is no mention of "ceiling height." 3.3.4 deals with enclosed areas and defines how to determine if an enclosed area is 5’ or less in height and whether it should or should not be included in GFA calculations. Please read 3.3.3(C)(6) again - It states "Fifty percent or more of the area has a ceiling height of seven feet or less.” "Ceiling height" are the key words 3.3.4 makes no mention of "ceiling height” and does not provide a definition for it. 3.3.4 only defines “height” as it relates to calculating GFA that is 5 ’or less in height The intent of 3.3.3(C) is to provide a pathway to exclude habitable attics. E-1/5-PRESENTATIONThe Bedroom 4/Office Area has a maximum ceiling height of 7’, is on the second floor and under the first floor roof The Habitable Attic area of the Bedroom 4/Office is in a section of the house that would also qualify for the non- habitable exemption 3.3.4 as it does not add any mass and does not have an exterior wall. The area at the Bedroom 4/Office is designed with a structural truss system in order to span the skylights added to meet the egress requirements. E-1/6-PRESENTATION• Floor Plan as Initially Submitted: • 100% of the shaded areas have a max ceiling height of 7 ’due to the egress skylights need for framing support from above to carry the load spanning the opening. The truss is part of the structural system of the roof- no portion of it would be removable or open to below. Green shaded area has a max ceiling height of 7’ E-1/7-PRESENTATION◦ ◦ ◦ Furthermore, one can begin to question the previous BOA interpretation on Attic Exemptions where anything less than 5’ in CEILING HEIGHT is excluded from the averaging calculations. Here, the BOA incorrectly applied the 3.3.4 definition of HEIGHT when in fact 3.3.3’s calculation criteria is specifically related to CEILING HEIGHT. If one can show 50% OR MORE of area has a CEILING HEIGHT of 7’ or less (while also satisfying 3.3.3(C)(1-5) then 3.3.4 is not relevant If you are applying for the 3.3.4 exemption, it is an entirely separate exercise, with an entirely different set of rules to qualify, and is based on a very specific HEIGHT definition that is not the same as CEILING HEIGHT. In Susan Barr’s own words from an email from April 15, 2021 she very clearly makes a distinction between ◦ CEILING HEIGHT and HEIGHT and further elaborates that CEILING HEIGHT is not measured to the underside of the top chord of a truss, but is in fact measured to the underside of the bottom chord of a truss, which is what actually defines CEILING HEIGHT. ◦ Susan Barr’s email was specific to Case# 2021-010924 PR regarding how to appropriately measure CEILING HEIGHT under a roof trussed structure - measure under the bottom of the top chord? Or measure under the bottom of the bottom chord? Susan’s email concurred that it is measured to the CEILING HEIGHT which is the bottom of the bottom chord. Susan Barr’s email further supports the arguments laid out here as she rightly points out that furring down the roof structure would potentially trigger the 3.3.4 rules regarding the applicability of enclosed areas less than 5 ’ high. ◦ A copy of Susan’s email is attached: E-1/8-PRESENTATION• On Apr 15, 2021, at 3:00 PM, Barr, Susan <Susan.Barr@austintexas.gov> wrote: Thank you for sending the email correspondence below. From yesterday’s meeting, two items were outstanding: dormer bearing on exterior wall and In reviewing the 2015 BOA determination re. dormers, the board did determine that a dormer just needs to be within the horizontal area of the roof • and not framed into the plane of the roof – meaning that it can bear on the exterior wall. However, so that 3rd floor attic walls are not created, the roof needs to wrap the bottom of the dormer. In regards to measuring height for an attic exemption, the BCM clearly calls out ceiling height for attic exemption though the BOA determine just says • height. With the BCM noting ceiling height, we go with ceiling height but keep in mind that furring down from the roof structure would not meet code. xxxx • height measurement for attics. • • • • • • • • • Best Regards, Susan E-1/9-PRESENTATIONBedroom 4/Office area is internally located in space below the roof that plates from the first floor to the second floor between the mechanical area and the rear vaulted ceiling of the bedroom below. This is well below the tent and does not add any mass to the structure. Note the Tent Location- there is no portion of the right side of the structure that penetrates the tent or even comes close. E-1/10-PRESENTATION• Building Criteria Manual: • 4.4.5.2 Attic Exemptions: Sufficient exhibits must be submitted within the plan set demonstrating compliance with Board of Adjustment decisions and Title 25-2 Subchapter F. • The following minimum items are required for review of exempted attics: • • • • The building elevations must clearly depict (and label) the slope of the roof(s) for the habitable attic area along with depicting that 1) acceptable construction for a habitable attic is being followed. 2) Provide a separate roof plan within your architectural plan set with all roof slopes identified (labeled) on it. The floor plans and building elevations must depict that the habitable attic is contained with the roof structure and does not extend beyond 3) the footprint of the floors below. 4) A separate floor plan and a section view of the habitable attic must be submitted depicting compliance with the Board of Adjustment interpretation from January 9, 2012 (C15-2011-0110) regarding: "As measured in accordance with Subsection 3.3.4, fifty-percent (50%) or more of the exempted portion of an attic must have a height of less than 7 feet, but more than 5 feet." Both exhibits (floor plan and section view) shall depict the attic areas that are: 1) less than 5 feet of ceiling height, 2) between 5 feet and just less than 7 feet of ceiling height, and 3) 7 feet and greater in the ceiling height. In addition, a tabular calculation based on the exhibits must be included demonstrating a valid ratio (expressed in sf or %) for a habitable attic exemption (i.e. the area with ceiling heights between 5' and less than 7' is greater than the area with ceiling heights 7' and greater). 3.3.4 is specific to areas that are 5 ’or less regarding the measurement- the BOA interpretation does not mention when 100% of the space is 7 ’and • below. The BOA interpretation DOES specify that the rooms are to be used for human occupation. This implies that they need to meet IRC regarding room size and configuration. E-1/11-PRESENTATION• A memo was requested from DSD clarifying their position and why the interpretation of ceiling height has changed on this project and when that was not produced, we proceeded to BOA. • The Habitable Attic space was designed per the 2021 IRC and meets the provisions of R326 Habitable Attic and R305.1 Minimum Ceiling height. • If the Staff Interpretation of measuring height based on 3.3.4 per BOA then it would be in direct conflict with 2021 IRC regarding ceiling height. Staff has also further directed that a Habitable Attic area with 100% of the proposed habitable space at 7’ ceiling height or below does not meet the 50% requirement of area between 5-7’ ceiling height. • We have been designing homes in Austin under the current code and amendments for many years and rely on consistent interpretations. The zoning code (LDC) gives us understanding of what each property can bear, the building criteria manual (BCM) is the rule book to apply, and the building code (2021 IRC) gives clear direction of how to build. • The Habitable Attic as proposed is utilizing an area that would normally be used for a storage or mechanical attic, that adds no mass to the structure and well within the McMansion tent, and designed to meet the needs of a family that needs dedicated space for remote learning and working. As our City grows and prices continue to push families out of our neighborhoods, we have an obligation to find ways of meeting the needs of a growing population by adding more flexibility into the home while meeting the requirements of the codes. E-1/12-PRESENTATION