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32C-174 274 Pleasant code review 2016-09-12Code Review Thomas Douglas Architects Inc. Optical Studio 274 Pleasant St, Northampton, MA 196 Pleasant St. Northampton, MA 413-585-0641 1 CODE REVIEW-REVISED September 12, 2016 The Optical Studio 274 Pleasant Street, Northampton, MA Applicable Building Code: MA 780 CMR Eighth Addition IBC, IEBC International EXISTING Building Code, 2009 ZONING DISTRICT: PROPOSED RENOVATIONS: PROJECT DESCRIPTION: • Construct a new single story addition on the rear of the existing building. • Make alterations to areas of the existing building. Use Groups • Existing use: B Business on the 1st floor. R2 Residential use on the 2nd floor. • Proposed use in new addition: B Business on the 1st floor Construction Type • 5B Chapter 10 requirements: Additions to Existing Buildings: Below are general requirements for the entire project and specific requirements for the proposed addition: 704.2, 912.2.1 Fire Protection: Automatic sprinkler systems Automatic sprinkler systems are NOT required in this project because of the exceptions in 704.2.2 and MGL 148 26G The following conditions are present: (IEBC) The B use in the building is less than 12,000 square feet. Table 903.2.2.1 All R2 uses are required to have sprinkler systems unless they meet the exceptions below: The Level 2 work area does not exceed 50% of the building floor area MGL 148 26G: Sprinklers are required if: The overall building area is greater than 7,500 square feet. • The total building area for this building is less than 7,500 square feet (5,641 square feet). Code Review Thomas Douglas Architects Inc. Optical Studio 274 Pleasant St, Northampton, MA 196 Pleasant St. Northampton, MA 413-585-0641 2 Major alterations are work which is “major” in scope or expenditure, and which results in changes affecting a substantial portion of the building” as defined in MGL 148 26G • The reconfigurations in the work area do not rise to the level of “major alterations” Major alterations or modifications are reasonably considered major in scope when such work affects 33% or more of the total gross square footage of the building, calculated in accordance with 26G. • The work area in the R2 area is less than 33% of the total gross square footage of the building. Major alterations or modifications are reasonably considered major in scope or expenditure when the total cost of the work (excluding costs relating to sprinkler installation) is equal to or greater than 33% of the assessed value of the subject building, as of the date of permit application. • The costs for this project within the R2 work area are less than 33% of the assessed value of the building. 704.4 Fire alarm and protection: The existing building has a fire alarm system. It will be upgraded and altered as necessary. • Manual fire alarm boxes are not required in Group B uses if: • Combined occupant load is less than 500 • Occupant load is less than 100 above or below the lowest level of exit discharge • Does not contain Group B ambulatory health care. • This project does not trip these thresholds. Seismic Zone • See structural drawings. Code Review Thomas Douglas Architects Inc. Optical Studio 274 Pleasant St, Northampton, MA 196 Pleasant St. Northampton, MA 413-585-0641 3 Fire Resistive Required Types of Construction, Table 601 & 602 Building Element Type 5B Primary Structural Frame 0 Bearing walls, Exterior 0 Bearing walls, Interior 0 Nonbearing walls and partitions, exterior- table 602-walls less than 5’ from property line 1 Nonbearing walls and partitions, interior 0 Floor construction and secondary members 0 Roof construction and secondary members 0 Table 503, 508.4.2:Allowable building area: 506.1 Building area modifications: Building areas from Table 503 shall be permitted to be increased due to frontage and sprinklers. • For B and R2 uses and type 5B construction, the building area (per floor) is within allowable height and area limitations. 508.4.2:Alowable building area: The building is within the allowable areas for the use and construction type. 903.2Fire areas Fire Resistance Rating for Exterior Walls 705.5 Fire resistance ratings: Exterior walls shall be fire resistance rated in accordance with Tables 601 and 602 Table 601: Bearing walls, exterior: 5B construction, B use: 1 hour Table 602: Nonbearing walls and partitions, exterior- table 602-walls less than 5’ from property line: The sides of this building will be less than 3 feet from the property line. The walls will be built with a 1-hour fire resistance rating. 705.8 Openings: For an unprotected un-sprinkled building, where the fire separation distance is less than 3 feet, the maximum area of exterior wall openings is 0%. This building meets this requirement. Code Review Thomas Douglas Architects Inc. Optical Studio 274 Pleasant St, Northampton, MA 196 Pleasant St. Northampton, MA 413-585-0641 4 705.11 Parapets: Exceptions A parapet need not be provided on an exterior wall where the following condition exists: 4.1 One-hour fire resistance-rated exterior walls that terminate at the underside of the roof sheathing, deck or slab, provided: The entire building shall be provided with not less than a Class A roof covering. This project will have 1-hour fire resistant rated exterior wall that will terminate at the underside of the roof sheathing. There will be a Class A roof covering consisting of an EPDM mechanically fastened membrane over1/4” Georgia Pacific Dens-Deck cover board, rigid foil-faced polyisocyanurate insulation, plywood decking, and wood roof rafters. EPDM by Firestone Platinum OCCUPANCY Occupant Load Calculation (IBC 1004.4.1) Proposed occupancy 1st floor B USE: 36 maximum occupants allowed. (100 gross square feet per occupant.) Means of Egress There will be 2 means of egress for the first floor areas. We propose to eliminate one of the 2nd floor apartment egresses which is a spiral stair. See below. We propose a new egress corridor shared by both apartments, leading to the existing front egress spiral stair. The stair exits directly to Main Street. 805.2 Means of Egress Lighting Means of egress lighting will be installed throughout the entire building 805.3 Exit signs Means of egress throughout the entire building will have new exit signs installed. 705.4.2 Door swing. All means of egress doors will swing in the direction of travel. 705.4.4 Panic hardware: Panic hardware is not required because the occupancy is not greater than 100 705.6 Dead end corridors No dead end corridors will exceed 35 feet. Code Review Thomas Douglas Architects Inc. Optical Studio 274 Pleasant St, Northampton, MA 196 Pleasant St. Northampton, MA 413-585-0641 5 Exits Required Exits required Exits provided Exit Width stair .3” per occupant Exit Width other components .2” per occupant First Floor 2 2 44” min 44” min Second Floor 2 2 36” min 36” Travel Distance (1016.1) With NO sprinkler System With sprinkler System Proposed max travel distance R use, 200 ft. 66 feet B use, 1st floors 200 ft. 68 feet 711 Energy Conservation Required values according to the MA stretch code MA: climate zone 5A Roofs: R-38 Walls above grade: R-13+R-7.5 ci= R20.5 Walls below grade: R-7.5 Slab on grade Floors, unheated: R-10 Level 2 work requirements: Existing Building The reconfiguration of space, the addition or elimination of any door or window, the reconfiguration or extension of any system, or the installation of any additional equipment. Below are requirements for the existing building: Alterations Level 2 – Reconfigure the existing first floor layout. Remove existing 2nd floor east spiral stair. Build new egress corridor to access west spiral egress stair. Occupant Load Calculation (IBC 1004.4.1) Proposed occupancy 2nd floor R2 use: 200 gross square feet per person equals 8 maximum occupants. 4 maximum occupants are proposed for the total R2 use. Means of Egress Alterations level 2, Section 705 .2 General: The means of egress shall comply with the requirements of this section 705.2: Exception 2.: Means of egress conforming to the requirements of the building code under which the building was constructed shall be considered compliant means of Code Review Thomas Douglas Architects Inc. Optical Studio 274 Pleasant St, Northampton, MA 196 Pleasant St. Northampton, MA 413-585-0641 6 egress if in the opinion of the code official they do not constitute a distinct hazard to life. The two existing spiral stairs were allowed by the code when this building was constructed. They are currently allowed under the IBC. The IBC new construction code allows spiral stairs as a means of egress within a single residence. We propose a change to these means of egress stairs. We propose to eliminate one of the 2nd floor apartment spiral egress stairs. We propose a new fire rated egress corridor shared by both apartments, leading to the existing front egress spiral stair. The stair exits directly to the sidewalk at the Street. This change is not allowed in the IBC. We would like to propose a compliance alternative: Section 1009.9 Spiral Stairways states” Spiral stairways are permitted to be used as a component in the means of egress only within dwelling units for from a space not more than 250 square feet in area and serving not more than five occupants… They shall have a 7 ½” tread depth at 12 inches from the narrow edge. The risers shall provide headroom of 78” and not more than 9 ½”. Minimum stairway clear width at and below the handrail is 26” 104.10 Modifications: This section allows the building official to amend or make exceptions to the code as needed where strict compliance is impractical. We are required to: • Show that our problem makes strict letter of the code impractical: o If we maintained the spiral stair from the east apartment, it would force egress to made into a small alley type space between our new addition and a neighboring building. This would be an unsafe option. o If we built a code compliant straight stair, it would occupy required Optical Studio business space on the first floor. • The modification is in compliance with the intent and purpose of the code: o We propose a new egress corridor in compliance with 709 below. o The existing spiral stair is in compliance with the code for spiral stair dimensions. See attached drawing. o There is currently a 1 hour rated ceiling between the 1st floor business use and the 2nd floor. Any changes we make in this area will be patched with 5/8” type X sheetrock, fire caulked and sealed. • The modification does not lessen health, accessibility, life and fire safety, or structural requirements: o The residential occupancy is very low- a maximum of 2 people per apartment equaling 4 people using this egress. The apartment space Code Review Thomas Douglas Architects Inc. Optical Studio 274 Pleasant St, Northampton, MA 196 Pleasant St. Northampton, MA 413-585-0641 7 is small. The east apartment is 860 square feet. The west apartment is 720 square feet. The egress at grade is directly to the sidewalk. The maximum travel distance is short- it is 66 feet from the most remote point of the east apartment to the first riser of the spiral stair. The wall construction around the remaining spiral stair is 1 hour rated construction. It has 1 layer of 5/8” sheetrock on both sides of the wall. We will still maintain 2 means of egress. The new egress corridor shall have emergency lights, exit signs, and fire alarm system. Both apartments are tied into an existing fire alarm system that will be upgraded and modified as necessary to be compliant to the IBC. IBC section 709 Fire Partitions: The proposed corridor is a “Fire Partition”. Fire Partitions are required for walls separating dwelling units from dwelling units and dwelling units from corridor walls. Fire partitions shall have a fire resistance rating of not less than 1 hour. Although 709.3 exception 1 allows corridor walls to have a ½ hour rating, this building does not have sprinklers and should therefore maintain the 1-hour rating. The doors shall be 1 hour rated. (IBC 420.2 and 709.1) Alterations level 2, General: 701.3 Compliance New electrical equipment must comply with section 708 Length of dead end corridors, comply with 705.6 There are no proposed dead end corridors. Minimum ceiling height of newly created habitable and occupied spaces shall be 7 feet. There are no newly created spaces. 705.4.4 Panic Hardware In level 2 work areas, Panic hardware is only required for A uses with occupancies over 100. This project does not have this occupancy count or use. 705.7 Means of Egress lighting All means of egress shall have compliant exit signs. 705.7 Exit Signs The tenant space shall have compliant egress lighting 711 and 607 Energy Conservation: Level 1 and 2 alterations are permitted without requiring the entire building to comply with the International Energy Conservation Code. Alterations (new construction) shall comply with the International Energy Conservation Code. Code Review Thomas Douglas Architects Inc. Optical Studio 274 Pleasant St, Northampton, MA 196 Pleasant St. Northampton, MA 413-585-0641 8 A building that undergoes Level 2 alterations is required to meet a certain level of energy compliance. Where there are reconfigurations of the space or new doors or windows, any such new element is required to meet the International Energy Conservation Code. Elements within the building that are not being affected do not heed to be evaluated and do not nee to comply with the energy provisions. Essentially the entire building is not required to meet the energy provisions; only a degree of possible improvement in the energy performance of the building is intended to be achieved by making the new elements meet the IECC. In certain cases where the reconfiguration of the space might have resulted in the creation of new spaces the newly created space should be evaluated as a whole for compliance with the energy provisions even though some of the element within the space might actually not have been altered. Likewise, in a case where an existing mechanical system is being extended to other areas or new ductwork is being installed to reconfigure and reroute the ducts to various spaces, it is only required to have the new elements meet the energy provisions and not the entire system. Any new replacement windows will have a maximum U value of 0.4 Any new entrance doors will have a maximum U value of 0.8 None of the existing exterior walls or roof are being altered, so no new insulation is required. 806 Accessibility CMR 521 Valuation of Project: • This project’s construction costs are: $540,000 • The assessed value of the building is: $202,600 • The cost of the project is 266% of the assessed valuation of the tenant space. 3.3.1 b. If the work costs $100,000 or more, then the work being performed is required to comply with 521 CMR. In addition, an accessible public entrance and an accessible toilet room shall be provided. 3.3.2 If the work performed, including the exempted work, amounts to 30% or more of the full and fair cash value of the building, the entire building is required to comply with 521 CMR. 3.3.3 Alterations by a tenant do not trigger the requirements of 3.3.1B and 3.3.2 for other tenants. This project’s construction costs are more than 30% of the assessed value of the building and more than $100,000. Code Review Thomas Douglas Architects Inc. Optical Studio 274 Pleasant St, Northampton, MA 196 Pleasant St. Northampton, MA 413-585-0641 9 The new addition will be built to accessible standards. The existing B use will be renovated to accessible standards. Schedule: Start construction fall 2016 Completion in 3 months End of Document NEW CLOSET SECOND FLOOR PLAN Scale: 1/2" = 1'-0"2 1' -0" 8"LANDING 2'-10"x2'-6"4 3/4"4 3/4" 1-HR RATED WALLS 1-HR RATED CEILINGS3SKA-12'-2" DISPLAY CASEFIRST FLOOR PLAN Scale: 1/2" = 1'-0"1 4 3/4"4 3/4"1' -0" 8" 15 RISERS = 9 1/4" 1-HR RATED WALLS 1-HR RATED CEILINGS3SKA-1Architects, Inc. The architect shall be deemed the author of these documents and shall retain all common, statuatory and other reserved rights including the copyright. Any changes to these drawings without the written consent of the architect shall void the accuracy of the plans. 196 Pleasant Street, Northampton, MA phone: (413) 585-0641 ISSUE: 274 PLEASANT STNORTHAMPTON, MA 01060 OPTICAL STUDIO DATE: THOMAS DOUGLAS SKA-1 SPIRAL STAIR DETAIL SCALE: AS NOTED ON DRAWING 09/12/2016 09/12/2016 DATE REVISED: STAIR SECTION Scale: 3/8" = 1'-0"3 15 RISERS = 9 1/4"9 1/4"TO HALLWAY EX. 1 HR RATED WALLS TOREMAIN 9'-0 1/2"