Detailing : Floor Assemblies

eu:a eppstein uhen architects 1

D E T A I L I N G S E M I N A R

FLOOR ASSEMBLIESp r e s e n t a t i o n


OUTLINE Floor Assemblies :

Overview Detailing Objectives

Composite : Concrete & Steel Deck

Wood Framed Floors + Ceilings

Post-Tensioned Concrete Floor


Detailing Objectives

DOB-1 : FIREDOB-2 : EARTHDOB-3 : WATERDOB-4 : AIR

DOB-5 : COSTDOB-6 : TIMEDOB-7 : SCOPE

FIRE

WATER

AIR EARTH

dryhot

wet cold

ELEMENTS

TIMECOST

SCOPE


Composite : Conc & Stl Deck Project : FIRST PLACE Project Scope

7+4 story vertical addition Existing structure : CIP

concrete Height : 12 story Floor Determination

Poor bearing capacity of soils

Condition of existing structure

Design and code parameters

Need : Light weight vertical

addition Solution :

Composite concrete & steel deck on steel structure


Composite : Conc & Stl Deck Occupancy :

Separated Mixed Use R-2 (multifamily) S-2 (parking) A-2 (restaurant & café) M (Proposed food

store) B (Dental clinic &

office)

Construction Type : 1B Non-combustible Construction materials

Concrete + Steel Other non-combustibles

Rated floor/ceiling assembly : UL D502


Composite : Design Objectives

DOB-1 : Fire (Thermal)

Conduction Balcony : every unit Thermal transmission

if slab edge is not insulated or not thermally broken

Design : moving target


DOB-2 Earth (Solid)

Material Interactions Different floor finish materials Ceramic tile :

Substrate : solid + moisture resistant Gyp Cement Underlayment Tile backer or concrete

Floating wood floors Substrate : solid + very flat Gyp Cement Underlayment Concrete

Single flooring system substrate

Movement Building = >300’ long Expansion joint required : 2” sliding

Existing & new floors Gypsum board ceilings

Composite : Design Objectives


Composite : Design ObjectivesDOB-3 Water (Liquids)

Drainage Most critical : Slab edge at

sliding doors Highly defined slab edge detail

Code : Maximum 3/4” threshold Water Pressure Test

Minimum 10 lb (high rise) Sliding doors : recessed 2” into

the slab edge Code compliant Weather resistant

Other Considerations Finish flooring Exterior balcony structure Exterior finish skin materials Flashings


Composite : Design ObjectivesDOB-4 Air (Vapor)

Acoustics IIC & STC ratings : 60+ (condo’s)

Concrete : best flooring substrate for condominiums because of its mass

Vibration loads Steel frames absorb & transmit much like

gravity loads Isolate vibration

Isolate structural members from sound transmitting assemblies such as ceilings & walls

Resilient materials below hard surface flooring

Provide a high density acoustic insulation Mineral wool above ceilings (STC

requirements) Suspended gypsum board ceiling

membrane Acoustic benefits Non-combustible fire protection for steel

frame


Composite : Design ObjectivesDOB-5 Cost

Labor Steel fabrication &

erection Repetitive members &

connections Flexible sequencing

Material costs : high(er) Offset by speed of erection Mill order = no $ surprises


Composite : Design ObjectivesDOB-7 Scope

Aesthetics Exposed Concrete =

“Industrial Loft” Suspended GB ceiling

membrane Fire protection of steel Clean smooth ceiling

Coordination MEP & FP installation

Difficult due to the numerous steel parts and pieces

Restricts unprotected MEP penetrations Non-rated ceilings :

suspended below rated ceilings

Exposed MEP & FP elements


Detailing – Detail on CD’s


Detailing – Detail on CD’s


Wood : Floor Systems

Major Concerns : Fire & Smoke Separation : UL & FM Acoustic Control : STC Vibration Control : IIC Structural : Diaphragm & Deflection


Wood : Design ObjectivesDOB-1 Fire (Thermal)Fire & Smoke Separation Prevent flame & hot gases Sprinkle interstitial spaces

(NFPA 13) Smoke Compartments (NFPA

13R) Smoke and Fire dampers :

MEP

DOB-2 Earth (Wind/Gravity)Structural concerns Diaphragm (Horizontal)

T&G sheathing Deflection (Vertical) : Bounce

Floor Finishes : Stone & ceramic tile

Ceiling Finishes : Control joints

Nails vs. Screws : Squeaky Floors!


Wood : Design ObjectivesDOB-3 WaterLeak Prevention Mold prevention : Flashings at exterior (wall +

floor) Floor drains : thresholds, recessed shower pans


Wood : Design Objectives

DOB-4 Air Acoustic Control Airborne sound vs.

Structure borne sound STC vs. IIC

Dwelling units : IIC 50 minimum (IBC

2006 1207.3)

Source for claims : Condos need higher STC

& IIC


Wood : Design ObjectivesDOB-4 Air Acoustic Control Sound reduction strategies

Decoupling : Sound reduction mats (Acousti-Mat)

Flexibility : Resilient channels Increase mass

Underlayments + Additional drywall + Mineral wool


Wood : Design Objectives


Wood : Design ObjectivesDOB-7 ScopeCoordination MEP coordination

Duct, pipe and cable runs

Forgiving Details Larger dimensional

tolerances Field modifications Finish flooring and

gypsum board ceiling can cover most imperfections.

DOB-5 CostMaterial & labor Wood is cheap! Easy fabrication & erection Repetitive members &

connections Flexible sequencing Field modifications

DOB-6 TimeSchedule & sequencing Avoid excess moisture

Plywood, OSB & GB : absorb water

Fabrication : short lead times


ResourcesGypsum Association GA 600-2006 FRDM (18th Edition)

Free download Includes STC/IIC/UL/FM tests http://www.gypsum.org/

GA60006.html

United States Gypsum (USG) SA100 – Fire-Resistant Assemblies SA200 – Acoustical Assemblies SA924 – Drywall-Wood Framed

Systems SA305 – Poured Cementitious Floor

Systems

Underwriters Laboratories Online Certifications Directory


Concrete : Post-Tensioned (PT) Project : ASTOR PLACE Project Scope

New Construction Light gauge steel frame Composite concrete +

steel deck Structural steel w/metal

roof deck Height : 18 story Floor Determination

Location + Cost Design + code

parameters Solution :

Post-tensioned concrete


Concrete : Post-Tensioned (PT) Occupancy :

Separated Mixed Use R-2 : multifamily S-2 : parking A-2 : tenant spaces M : tenant spaces B : tenant spaces

Construction Type : 1A Non-combustible Construction materials

Concrete + Steel Other non-combustibles

Rated floor/ceiling assembly : ?


Concrete : Post-Tensioned (PT)


PT Concrete : Design Objectives

DOB-1 Fire (Thermal)

Conduction Thermal transmission

if slab edge is not insulated or not thermally broken

Owner : thermal breaks not needed at the cantilevered PT concrete balconies.



DOB-2 Earth (Solid)

Material interactions Finish Materials

Finish flooring material to structural (A5100; A0010(B4); Underlayment) substrate.

Ceramic tile & Floating wood floors Substrate : solid + moisture resistant Gyp Cement Underlayment

Self leveling Underlayment Lower cost of the wood floor installation Imperfections : covered up

Carpet floors Do not require the flatness of the above floor finishes Standard padding vs. Acoustical carpet pad

Movement Potential for damage or Recurring maintenance Differential movement : joints between PT Conc +

Steel structure Gypsum board ceilings

GB expansion joints : primary structural members



DOB-3 Water (Liquids)

Most critical : Slab edge at sliding doors Highly defined slab edge detail

Code : Maximum 3/4” threshold

Water Pressure Test Minimum 12 psf (high rise)

Sliding doors Recessed 1.75” into the slab

edge Code compliant Weather resistant


DOB-3 Water (Liquids)

DrainageOther Considerations Finish flooring (1.25” depth) Window wall systems Wall system transitions Typical slab edges Roof intersections




DOB-4 Air (Vapor)Acoustics IIC & STC ratings : 60+ (condo’s)

PT concrete : Best structural floor system for condos Mass and stiffness

Isolation of structural members from Isolate vibration

Walls : Prevent unit-to-unit sound transmission

Resilient materials below hard surface flooring

Provide a high density acoustic insulation Mineral wool above ceilings (STC

requirements) Suspended gypsum board ceiling

membrane Acoustic benefits



DOB-5 CostLabor and Materials Light gauge steel : 2 story townhomes

Cost Savings In lieu of PT Conc Units : changed to single story

Deciding Factor : PT Conc Height Stiffness Structural depth

8” at most residential floors)



DOB-7 Scope

Aesthetics Concrete structure : concealed

Buried or wrapped in Gyp Bd Perimeter columns (round) are left exposed.

Coordination MEP coordination : during the SD and DD phases

Various ceiling systems Structural penetrations.

Light gauge steel Suspended gypsum board ceiling : fire rated membrane Restricts the number & size : unprotected MEP penetrations. Coordination with MEP & FP System design : parameters of the code.


Conclusion

Questions???

Comments???

Concerns???

Suggestions???


Detailing : Sequencing

B. Mtl studs + balcony structure & deckingA. Steel structure + composite floor slabC. Exterior sheathing + plywood blocking + weather barrier @ frames

D. Mtl flashing @ framesE. Exterior weather barrier over sheathingF. Frames installedG. Exterior finish (EIFS) + sealants + exterior wall insulation

H. Interior vapor barrier + floor toppingI. Interior gyp bd + window stool + finishes (wall & floor)