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25C-071 FireSeparationPlan42DayAvenue_5.542-4 Day Avenue Northampton Fire Separation Plan 5/1/2015 Type A B C D E F A-1 Locations First Floor Ceilings (1st floor apartment) Second Floor Ceilings (2nd Floor apartment, common hallway and 2nd floor apartment front closet, 3rd floor apartment's 2nd floor entry room) Apartment Walls Abbutting Back Stairwell (1st and 2nd floor kitchens, 1st floor laundry/back entry room, 2nd floor Master Bedroom closet wall); Apartment Walls Abbutting Front Stairwell (1st floor front bedroom and front bedroom closet, 2nd floor Bedroom 2 and living room walls abutting front staircase and 2nd floor foyer of 3rd floor apartment); Front and Back Stairwell Walls; Wall between 3rd floor apartment's entry/laundry room on 2nd floor and 2nd Floor apartment living room, 2nd floor front hallway walls (above stair doorway opening at top of stairs where exit sign is located, hallway closet walls abutting staircase, abbutting 2nd floor apartment front bedroom/living room/dining room); Basement walls abbutting back staircase (closet interior walls beneath staircase, 2nd Floor common hallway/hallway closet wall abbutting 3rd floor apartment's 2nd floor entry/laundry room Various conditions not listed in code or unknown conditions. Ceilings in and beneath Stairwells (front and back stairwell ceilings, ceiling in 1st floor apartment front bedroom closet, ceiling in basement closet (3rd Flr apartment section of basement), ceiling in 1st Floor Apartment Front Entryway (1-story addition to house); Basement common area interior wall abbutting back staircase; Existing solid core raised panel doors between staircases/hallways and existing apartments New Third Floor Apartment and Stairwell Walls (walls abbutting front stairwell in 3rd floor dining/living room, walls abbutting back stairwell in crawlspace/closet/family room/master bedroom, wall in 2nd floor entry/laundry room abbutting 2nd Floor common hallway) Variants 1st Floor Apartment: Ceiling in former Bathroom Closet area, Ceiling in Bedroom 2 Closet (Middle Bedroom), Ceiling in Bedroom 1 Closet (Back Bedroom) Existing Condition 2" x 7 and 3/4" joists, 1" strapping, 5/16" lathe, 5/16" plaster, 3/4" air gap, 1/4" gypsum board, 3/8" gypsum board. Deck: 7/8" T&G, 1x6" subfloor boards. 16" O.C. 15' clear span with bridging at center. 3 and 1/2" x 6" joists (original plus sistered joists), 5 & 1/2" denim insulation, 3/8" lathe, 3/8" plaster (3/4" total plaster/lathe), 1/2" gypsum board. 16" O.C. Deck: 3/4" plywood + 7/8" T&G 2 x 4" studs, 3/8" wood lathe, 1/4" plaster (5/8" total thickness on each side). Total wall thickness: 5 and 1/4" 1.5" x 3.5" studs, 1/2" drywall. Total wall thickness: 4.5" Staircase ceilings: Stringer cavity, 5/16" lathe, 5/16" plaster, Deck: 3/4" Stair Treads. 1st floor apartment front entryway ceiling: drywall with unknown framing construction. etc. 5/8" drywall over 3&1/2" studs or 4" studs Same construction as A, except no air gap or additional gypsum or plaster/gypsum board beneath original plaster. Building Code Reference (Existing Buildings Code Unless Otherwise Specified) Table 2.2 Floor/Ceiling Assemblies F/C-W-10 12" clear span, 2" x 7" wood joists; 15" o.c.; 2" x 1.5" bridging at center; Deck: 1" nominal lumber; Membrane: 5/8" gypsum plaster on wood lath (27 minutes); Table 1.5.1 Finish Ratings Inorganic Materials F.R.-I-16 1/2" gypsum wallboard (15 minutes). IBC 2012 TABLE 722.6.2(2) Wood Floor and Roof Joists (10 minutes). IEBC 2009 Table 1.5.1 Finish Ratings Inorganic Materials F.R.-I-12: 1/2" thick 1:2; 1:3 gypsum plaster on wood lath (15 minutes) and F.R.-I-16 1/2" gypsum wallboard (15 minutes). W-4-W-40: 2"x4" stud wall; 1/2" thick, 1:2, 1:3 gypsum plaster on wood lath on both faces (30 min) W-4-W-33: 4 1/2" thickness. 2" x 4" stud wall; 1/2" gypsum wallboard on both faces (40 min) Staircase assemblies are not listed in Existing Buildings Code. 5/8" drywall on 1.5" x 3.5" studs (1 hr) Same as A, but 15 minutes less protection due to no additional gypsum/plaster beneath original plaster ceiling. Current Fire Rating (Minutes) 42 40 30 40 0 60 27 Additional Protection Required (Minutes) 18 20 30 20 60 0 33 Proposed Method* Intumescent Paint 15 mils dry / 1 hour Intumescent Paint 15 mils dry / 1 hour Intumescent Paint 15 mils dry / 1 hour Intumescent Paint 15 mils dry / 1 hour Intumescent Paint 15 mils dry / 1 hour on plaster/gypsum surfaces and 20 mils dry / 1 hour on wood surfaces No Action Required Intumescent Paint 15 mils dry / 1 hour Questions/Comments Note 1: Compared to existing building code conditions provided, actual conditions provide greater fire protection: Joists are 3/4" deeper, there is a 3/4" air gap, and gypsum/plaster board assembly is 1/16" thicker (gypsum board is 1/8" thinner but gypsum/plaster board is 3/16" thicker). Note 2: First floor bathroom ceiling has same construction as A through the original plaster, then a drop ceiling with 1/2" gypsum board. Existing fire rating is same as A but has larger gap and 1/2" gypsum instead of 1/4" gypsum + 3/8" gypsum board. We weren't able to find insulation for ceiling assemblies in the code (in wall assemblies insulation adds 30 minutes), so the denim insulation was not counted toward the existing fire rating. Denim insulation is Class A fire rated. Note 1: In existing kitchen walls with cabinets, may we paint exposed surfaces only? Note 2: On both sides of 2nd floor living room wall assembly (common hallway/3rd floor entry room on other side), we butted 1/2" drywall to existing plaster in former location of french doors but otherwise existing walls are 1/4" plaster. Fire rating is slightly higher for the assembly in locations with 1/2" drywall (W-4-W-28 is 37 minutes). Note 3: On staircases from 2nd to 3rd floor, we butted 5/8" fire rated drywall to the existing plaster; the new walls with 5/8" drywall already have 1 hr protection and only the existing walls will be treated with intumescent paint. Note 4: Staircase exterior walls also have blown in cellulose insulation, which has not been counted in the existing fire rating. Note 5: In the back staircase, the exterior foundation wall is 8.5" thick; all listed masonry wall assemblies above 8" thick have at least a 45 minute fire rating (cored and solid brick assemblies all exceed 2.5 hours); these areas will be treated the same as the rest of the stairwells and will be treated with 30 minutes of intumescent paint fire protection. Part of this wall also has denim insulation in it but this was not counted toward fire rating. Note 1: 1st floor apartment front bedroom closet also has wood paneling. Note 2: Wall between basement and back stairwell is more of an extended door than a wall, consisting of operable 1/2" wood panels with latches allowing for panel to open to provide wider access to basement from the back door/stair. Per fire rated door specifications, these panels are to be painted on all sides. Note 3: The historical doors are constructed of solid core raised panel doors that are 1 and 5/8" thick with 5 thinner panels that are 5/8" thick. Note: spray foam insulation on exterior walls Note: Former bathroom closet area - we previously removed the closet and the ceiling was higher than in the rest of the bathroom.