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23A-061 Code Outline 63 maple street florence ma DRAFT 22 June 2018BUILDING CODE WORKSHEET 63 Maple Street, Florence, MA DRAFT FOR REVIEW June 22, 2018 Building Code Review – Performance Compliance Method (IEBC 2015 Chapter 14) Prepared by Jody Barker, AIA | Architecture & Design, LLC 32 Willow Street, Florence, MA mobile: 617-216-5988 e-mail: jodybarker.aia@gmail.com Building Summary Existing building use = Multi-use R-3 (2-family residence) in left half of building, B use group, right half of building (beauty salon) Proposed building use = Single-use, R-2 (apartment, 3-family) Year Built = 1900 Building construction = 5B (unprotected wood framed house) Existing building area = approximately 3,120 SF gross square footage 968 SF basement 1,184 SF 1st floor 968 SF 2nd floor Existing building height, feet = 23' Existing building height, stories = 2 Completely suppressed = no Corridor wall ratings = no corridors, tenants separated. Compartmentation = 1-hr rating between tenants Fire-resistance rating at vertical opening enclosures = 0-hr to less than 1-hr as currently constructed Type of HVAC = Hot air furnace services the existing apartments, mini-split system proposed for new residence. Automatic fire detection = yes Smoke Control = no Exit routes = direct access to exterior from all three apartments. The 1st floor, existing and the 2nd floor, existing apartments share one egress through a shared stair hall. This stair hall directly exits to the exterior. The 1st floor, existing and proposed new apartment exit directly outside via porches. The 2nd floor, existing apartment has its second egress via a private porch and stairs at the rear of the building. The proposed new apartment will have its second means-of-egress directly to the exterior via a porch at the front. Dead Ends = no Maximum travel distance = approximately 33' Elevator = no Means of egress emergency lighting = no (required by Code) Mixed occupancies = yes (existing), no (proposed) Standpipes = none Incidental use = none Performance Compliance Review for 63 Maple St., Florence, MA 1 of 10 BUILDING CODE WORKSHEET 63 Maple Street, Florence, MA DRAFT FOR REVIEW June 22, 2018 CALCULATIONS FOR WORKSHEET IEBC 1401.6.1 - Building Height Building height formula: Height value, feet ((AH-EBH)/12.5) x CF Height value, stories (AS-EBS) x CF AH = allowable height in feet (Section 504 of IBC) EBH = existing building height in feet AS = allowable height in stories (Section 504 IBC) EBS = existing building height in stories CF = 1, if (AH – EBH) is positive CF = construction-type factor shown in IBEC table 1401.6.6(2) if (AH-EBH) is negative AH = 40' (type 5B, no sprinklers, table 504.3) AS = 2 (type 5B, no sprinklers, table 504.4) EBH = 23 EBS = 2 AH-EBH = 40 – 23 = 17 Number is positive, so CF = 1 Height value, feet: (40-23)/12.5) x 1 = 1.36 Height value, stories: (2-2) x 1 = 0 0<1.36, therefore building height calculation is 0 Performance Compliance Review for 63 Maple St., Florence, MA 2 of 10 BUILDING CODE WORKSHEET 63 Maple Street, Florence, MA DRAFT FOR REVIEW June 22, 2018 IEBC 1401.6.2 - Building Area Allowable area formula (IEBC 1401.6.2.1): Aa = At + (NS X 1f) Aa = Allowable area per story, SF (IBC 506) At = tabular allowable area factor – NS, S1 S13R or SM (IBC 506) NS = tabular allowable area factor for no sprinklers per IBC 506.2 Factored regardless of whether the building is sprinklered or not If = area factor increase due to frontage per IBC 506.3 Frontage Calculation, If: •63 Maple Street has approximately 81.5' of frontage on Maple Street. •The building sits approximately 46' off of Maple Street. •The building can also be accessed on its side and rear via a shared driveway and parking area which wrap the building on the south and west sides of the property. The driveway is approximately 12' wide. It is approximately 7' off of the west side of the structure. There is between 20' to 22' of space between the building and the west property line. A shared parking area to the south (rear) of the structure is approximately 20' off of the building. •Station 2 of the Northampton Fire Department is directly to the east of the structure. •For the purpose of this exercise, it is assumed that the Fire Department will be able to access the east side of the property directly from their station in event of an emergency. If =[F/P-0.25]W/30 F = building perimeter that fronts on a public way or open space in feet P = perimeter of the entire building in feet W= width of the public way or open space Where the value of W is greater than 30', a value of 30' shall be used in calculating the building area increase based on frontage regardless of the actual width. The narrowest frontage or access is 20', therefore W = 20 F = 44+46+44+46 = 180 P = 28+22+12+22+34+12+18+32 = 180 W= 20 If =[F/P-0.25]W/30 If =[180/180-0.25]20/30 Performance Compliance Review for 63 Maple St., Florence, MA 3 of 10 BUILDING CODE WORKSHEET 63 Maple Street, Florence, MA DRAFT FOR REVIEW June 22, 2018 If =[1-0.25]20/30 If =[.75]20/30 If =15/30 If =0.5 At (table 506.2) = 7,000 SF NS; 7,000 SF S13R; 28,000 SF S1; 21,000 SF SM Allowable area calculation (IEBC 1401.6.2.1): Aa = At + (NS X 1f) Aa = 7000 + (7000 X .5) Aa = 7000 + 3500 Aa = 10,500 SF per floor Allowable area (Aa) calculation, single occupancy, multiple story building calculation (IBC 506.2.3): Aa = [At + (NS X 1f)] x Sa Sa = Actual building stories above grade, not to exceed 3 Sa = 2 Aa = 10,500 x 2 Aa = 21,000 Area formula (IEBC 1401.6.2.2) Area Valuei = (Allowable Areai / 1200 SF)(1-(Actual Areai / Allowable Areai)) 1st floor area: 1,184 2nd floor area: 968 SF Total occupied area: 2,152 SF Area Valuei = (Allowable Areai / 1200 SF)(1-(Actual Areai / Allowable Areai)) Area Valuei = (21,000 / 1200 SF)(1-(2,152 / 21,000)) Area Valuei = (17.5)(1-0.10) Area Valuei = (17.5)(.9) Area Valuei = 15.75 Maximum value permitted is 50% of the mandatory fire safety score (MFS) from table 1401.8 MFS for R occupancy = 21 50% of MFS/R = 10.5 15.75>10.5, Building area therefore is 10.5 Performance Compliance Review for 63 Maple St., Florence, MA 4 of 10 BUILDING CODE WORKSHEET 63 Maple Street, Florence, MA DRAFT FOR REVIEW June 22, 2018 IEBC 1401.6.3 - Compartmentation •Floor & wall construction is less than 2-hr construction. •The existing gross square footage of the building is 3,120 SF (including unoccupied basement spaces). •Existing compartment size of 5,000 SF = 16 IEBC 1401.6.4 - Tenant & Dwelling Unit Separations •Walls between existing tenant spaces at the 1st floor are constructed with 1/2” sheet rock or plaster w/ 3/8” lath on wood studs – 1-hr rated. •The ceiling between the 1st and 2nd floor occupancies is 1/2” plaster on lath over wood joists – 3/4-hr rated. •Tenant & dwelling separation determined to be category “C” from table 1401.6.4 for the existing apartments. •A 2-hr rated wall is proposed to separate the new duplex apartment from the existing 1st and 2nd floor apartments – category “E” from table 1401.6.4 •Separation value for R-use is 0 for category C (lowest level of performance). IEBC 1401.6.5 - Corridor Walls •The existing 1st floor apartment has access directly outside via porch and through an enclosed stairway (see vertical openings below) •The existing 2nd floor apartment has 2 means of egress via the shared, enclosed stairway and to the rear via porch with stairs directly to grade. •The proposed 3rd duplex apartment would have egress directly to the exterior at the front and rear of the apartment via porches. •There are no corridors in the building – category type “C” for R-use from table 1401.6.5 •Corridor walls value is 0 for R-use, category “C” IEBC 1401.6.6 - Vertical Openings •There is one (1) shared stairway for egress from the existing 2nd floor apartment. •It has plaster walls on wood studs. There are three (3) unrated door openings to this stair hall – two (2) connecting to the 1st floor, apartment and one (1) to the 2nd floor apartment. •The walls are 1/2” plaster on 3/8” plaster lath on each side of 2x4 studs similar to wall construction type W-5-W-70, table 1.3.2, Resource A of the IEBC 2015 – 1-hr. •The wall is in some disrepair with cracks and areas with loose plaster which need to be addressed. •Assume a protection value of “no protection” from table 1401.6.6(1) in IEBC until repaired: -2 •Vertical opening formula: VO = PV x CF where PV is the “protection value” (above) and CF is Performance Compliance Review for 63 Maple St., Florence, MA 5 of 10 BUILDING CODE WORKSHEET 63 Maple Street, Florence, MA DRAFT FOR REVIEW June 22, 2018 “construction-type factor” from IEBC table 1401.6.6(2). ◦PV = -2 ◦CF = 7 ◦VO = -2 x 7 = -14 IEBC 1401.6.7 - HVAC Systems •The building has central heating systems (hot air furnace) to service the existing 1st and 2nd floor apartments in the building. Supply and return ductwork serve individual floors and are enclosed in a chase or partition walls. •Bathroom fans directly exhaust. •Existing ductwork serving the new apartment will be removed during the renovations. •The proposed, new apartment will be heated and cooled via mini-split HVAC systems. •Existing apartments: IEBC 1401.6.7.1 HVAC Category “D” (central HVAC code compliant): 0 •New apartment: IEBC 1401.6.7.1 HVAC Category “E” (central HVAC without ductwork): 5 •Use value of “0” for the table. IEBC 1401.6.8 - Automatic Fire Detection •An interconnected smoke and CO detector system has been installed in the building in the existing 1st and 2nd floor apartments. •The new apartment will install new smoke & CO detectors and tie them into the existing system. •IEBC table 1401.6.8 Automatic Fire Detection Values, category “E” for R-use: 6 IEBC 1401.6.9 - Fire Alarm Systems •Fire alarm system evaluation from IBC 907.2 for use group R-2 •Manual fire alarm system – not required per 907.2.9.1, exception 1 ◦Manual fire alarm system not required in a building not more than 2 stories in height, 1-hr separations, and each dwelling unit has an exit directly to the exterior or public way. ▪All three units have two (2) means of egress which connect to the exterior of the building. •Smoke alarms – a new, interconnected smoke alarm system will be installed throughout the building. •Fire Alarm Systems evaluation, IEBC table 1401.6.9, category “C” for R-use: 0 IEBC 1401.6.10 - Smoke Control •There are operable windows in all three (3) dwelling units. Performance Compliance Review for 63 Maple St., Florence, MA 6 of 10 BUILDING CODE WORKSHEET 63 Maple Street, Florence, MA DRAFT FOR REVIEW June 22, 2018 •All apartment units have at least one (1) direct access to the building exterior via porch or stair. •The existing 1st and 2nd floor apartments have access to a shared stair hall which has egress to the building exterior. ◦There are no operable windows or pressurization in this stair hall, but there is an operable exterior door with direct access to the exterior. •There is no sprinkler system installed in the building. •IEBC table 1401.6.10 Smoke Control Values, category “A” for R-use: 0 IEBC 1401.6.11 - Means of Egress capacity & number •Each dwelling unit has two (2) means of egress to meet the minimum required number. •Door capacity exceeds the required measurements for all three apartments. •IEBC table 1401.6.11 Means of Egress Values category “C” for R-use: 0 IEBC 1401.6.12 - Dead Ends •There are no dead end corridors in the structure. •IEBC table 1401.6.12 Dead End Values, category “C” for R-use: 2 IEBC 1401.6.13 - Maximum exit access travel distance •Formula: ◦Points = 20 x ((max. allowable distance – actual distance)/max. allowable distance) •Table IBC 1017.2 Exist Access Travel Distance – R-use: 200' max., unsprinklered. •Travel distance, existing: ◦The longest travel distance in the new, duplex apartment is approximately 33'. ◦The longest travel distance in the 2nd floor apartment is approximately 30'. ◦The longest travel distance in the 1st floor apartment is approximately 30'. ◦Use 33' in formula above. •Travel distance formula: ◦20 x ((200'-33')/200') ◦20 x (167'/200') ◦20 x 0.835 = 16.7 IEBC 1401.6.14 - Elevator Control •IEBC 1401.6.14 Elevator Control assumes all buildings over 1-story height should have an elevator installed. •The floor to floor distance is less than 25' in height. •From IEBC table 1401.6.14 Elevator Control Values: less than 25' travel, category “A” = -2 Performance Compliance Review for 63 Maple St., Florence, MA 7 of 10 BUILDING CODE WORKSHEET 63 Maple Street, Florence, MA DRAFT FOR REVIEW June 22, 2018 IEBC 1401.6.15 - Means of egress emergency lighting •The existing, 1st floor apartment has one mean of egress directly to the exterior and one through a shared stair way. •The existing 2nd floor apartment has one means of egress directly to the exterior and one through a shared stair way with the 1st floor apartment. •The new, duplex apartment has two means of egress directly to the exterior. •There are no sprinklers installed with the building. •Because there are no sprinklers, emergency lights will be required. •Propose to install battery backed exit sign with emergency light in the shared stair between the 1st and 2nd floor apartments to bring to IEBC table 1401.6.15 Means-of-Egress Emergency Lighting Values, two or more exists category “B” level – 0 points. IEBC 1401.6.16 - Mixed Occupancies •The building will have one (1) occupancy – R-2 •0 points IEBC 1401.6.17 - Automatic Sprinklers •Sprinklers are required for R-2 use •Sprinklers are not installed in the building •IEBC Table 1401.6.17 Sprinkler System Values, R-use, category “A” - -6 •Per IEBC 1401.6.17, enter above value divided by 2 in the “means of egress” category - -3 IEBC 1401.6.18 - Standpipes •The height of the lowest (basement) and highest (2nd) floor level to be accessed by the Fire Department is less than 30'. •Standpipes are not required per IBC 905.3.1 •IEBC table 1401.6.18 Standpipe System Values, R-use, category “B” - 0 points IEBC 1401.6.19 - Incidental Uses •The building will be a single, R-2 use with three (3) apartments. •0 points IEBC 1401.6.20 - Smoke compartmentalization •No credit can be awarded for smoke compartmentalization per IEBC table 1401.6.20 Smoke Performance Compliance Review for 63 Maple St., Florence, MA 8 of 10 BUILDING CODE WORKSHEET 63 Maple Street, Florence, MA DRAFT FOR REVIEW June 22, 2018 Compartmentalization Values for a R-use structure. •0 points IEBC 1401.6.21 - Patient Ability, concentration & attendant to patient ratio •This is a R-2 use structure. IEBC section 1401.6.21 does not apply to this evaluation. Safety Score Calculations, existing •See attached spread sheet #1 for entries. •Mandatory Safety Scores (IEBC table 1401.8) ◦Fire Safety (MFS), R-use: 21 ◦Means of Egress (MME), R-use: 38 ◦General Safety (MGS), R-use: 38 •Results, spreadsheet #1 ◦FS = 10.5 ◦ME = 32.2 ◦GS = 29.2 •Formulas: ◦FS-MFS ≥ 0: 10.5 – 21 = -10.5 fail ◦ME-MME ≥ 0: 32.2 – 38 = -5.8 fail ◦GS-MGS ≥ 0: 29.2-38 = -8.8 fail As the building presently exists, it does not pass the performance test for compliance. Suggested Improvements: Installation of an automatic sprinkler system would add positive points in its category and positively influence other categories. An automatic sprinkler system is cost-prohibitive for the building owner at this moment. The above analysis assumes the installation of an emergency light with battery-backup in the shared stair hall between the existing 1st floor and 2nd floor apartments. •Because the building is not sprinklered, consideration of single exits and travel distance to the single exit cannot be considered. •The new apartment unit will have its own means of egress directly to the exterior via two (2) porches. •The 1st and 2nd floor apartments have one, separate means of egress directly to the exterior each as well as the shared stair way. •This analysis proposes to install an exist sign with emergency light and battery-backup in the shared stair hall to satisfy the emergency light requirement. Performance Compliance Review for 63 Maple St., Florence, MA 9 of 10 BUILDING CODE WORKSHEET 63 Maple Street, Florence, MA DRAFT FOR REVIEW June 22, 2018 The largest deficit of performance points is in the vertical openings section (1406.6.6). •The existing plaster on the walls in the shared stairs in the front, shared stair way is cracked, and the three (3) doors accessing the stair way are not rated. Because of these conditions, a “vertical opening protection value” (IEBC 1401.6.6(1)) of “-2” was used. When connecting two floors in type 5B construction, a vertical openings score of -14 was obtained. •Suggested improvements: ◦Repair or replace the areas of cracked plaster with new plaster of similar type. ◦Remove one (1) door accessing the 1st floor apartment and infill with new 1-hr rated infil. ▪2nd mean of access to the stair hall is not needed for the 1st floor apartment. ◦Remove existing, non-rated doors at the shared stair hall. Replace with new, 45-min. rated door and frame with closers. ◦These improvements would result in a 1-hr enclosure to the shared stairway, which would result in a vertical opening protection value of “2”. (Maximum positive value is “2” per 1401.6.6) One additional improvement is to build a higher rated demise wall between the new duplex apartment and the existing 1st and 2nd floor apartments. Building a 2-hr rated demise wall between the new duplex apartment and the existing 1st and 2nd floor apartments would create smaller compartments within the building (less than 2,500 SF). This would increase the value of category 1401.6.3 from 16 points to 22 points. Safety Score Calculations, with vertical opening improvements & 2-hr demise wall •See attached spread sheet #2 for entries. •Mandatory Safety Scores (IEBC table 1401.8) ◦Fire Safety (MFS), R-use: 21 ◦Means of Egress (MME), R-use: 38 ◦General Safety (MGS), R-use: 38 •Results, spreadsheet #2 ◦FS = 32.5 ◦ME = 54.2 ◦GS = 51.2 •Formulas: ◦FS-MFS ≥ 0: 32.5 – 21 = 11.5 pass ◦ME-MME ≥ 0: 54.2 – 38 = 16.2 pass ◦GS-MGS ≥ 0: 51.2-38 = 13.2 pass Performance Compliance Review for 63 Maple St., Florence, MA 10 of 10 Sheet1 - Existing Building Page 1 Table 1401.7 – Summary Sheet Building Code (IEBC 2015) Spreadsheet #1 - Existing conditions & renovations – 63 Maple Street, Florence, MA Prepared by Jody Barker, AIA| Architecture & Design, LLC, Florence, MA Safety Parameters 1401.6.1 Building Height 0 0 0 1401.6.2 Building Area 10.5 10.5 10.5 1401.6.3 Compartmentation 16 16 16 1401.6.4 Tenant & Dwelling Unit Separations 0 0 0 1401.6.5 Corridor Walls 0 0 0 1401.6.6 Vertical Openings -14 -14 -14 1401.6.7 HVAC Systems 0 0 0 1401.6.8 Automatic Fire Detection 6 6 6 1401.6.9 Fire Alarm System 0 0 0 1401.6.10 Smoke Control N/A 0 0 1401.6.11 Means of Egress N/A 0 0 1401.6.12 Dead Ends N/A 2 2 1401.6.13 Maximum Exit Travel Distance N/A 16.7 16.7 1401.6.14 Elevator Control -2 -2 -2 1401.6.15 Means of Egress Emergency Lighting N/A 0 0 1401.6.16 Mixed Occupancies 0 0 0 1401.6.17 Automatic Sprinklers -6 -3 -6 1401.6.18 Standpipes 0 0 0 1401.6.19 Incidental Uses 0 0 0 1401.6.20 Smoke Compartmentation 0 0 0 1401.6.21.1 Patient Ability for Self-Preservation N/A N/A N/A 1401.6.21.2 Patient Concentration N/A N/A N/A 1401.6.21.3 Attendant-to-Patient Ratio N/A N/A N/A Building Score – total value 10.5 32.2 29.2 Evaluation formulas: MFS for R-use 21 MME for R-use 38 MGS for R-use 38 10.5 21 -10.5 fail 32.2 38 -5.8 fail 29.2 38 -8.8 fail Fire Safety (FS) Means of Egress (ME) General Safety (GS) FS-MFS > 0 ME-MME > 0 GS-MGS > 0 Sheet2 - Proposed Improvements Page 2 Table 1401.7 – Summary Sheet Building Code (IEBC 2015) Spreadsheet #2 – Proposed upgrades – 63 Maple Street, Florence, MA Prepared by Jody Barker, AIA| Architecture & Design, LLC, Florence, MA Safety Parameters 1401.6.1 Building Height 0 0 0 1401.6.2 Building Area 10.5 10.5 10.5 1401.6.3 Compartmentation 22 22 22 1401.6.4 Tenant & Dwelling Unit Separations 0 0 0 1401.6.5 Corridor Walls 0 0 0 1401.6.6 Vertical Openings 2 2 2 1401.6.7 HVAC Systems 0 0 0 1401.6.8 Automatic Fire Detection 6 6 6 1401.6.9 Fire Alarm System 0 0 0 1401.6.10 Smoke Control N/A 0 0 1401.6.11 Means of Egress N/A 0 0 1401.6.12 Dead Ends N/A 2 2 1401.6.13 Maximum Exit Travel Distance N/A 16.7 16.7 1401.6.14 Elevator Control -2 -2 -2 1401.6.15 Means of Egress Emergency Lighting N/A 0 0 1401.6.16 Mixed Occupancies 0 0 0 1401.6.17 Automatic Sprinklers -6 -3 -6 1401.6.18 Standpipes 0 0 0 1401.6.19 Incidental Uses 0 0 0 1401.6.20 Smoke Compartmentation 0 0 0 1401.6.21.1 Patient Ability for Self-Preservation N/A N/A N/A 1401.6.21.2 Patient Concentration N/A N/A N/A 1401.6.21.3 Attendant-to-Patient Ratio N/A N/A N/A Building Score – total value 32.5 54.2 51.2 Evaluation formulas: MFS for R-use 21 MME for R-use 38 MGS for R-use 38 32.5 21 11.5 pass 54.2 38 16.2 pass 51.2 38 13.2 pass Fire Safety (FS) Means of Egress (ME) General Safety (GS) FS-MFS > 0 ME-MME > 0 GS-MGS > 0