The Design, Operation, and Maintenance of Building Systems, Part I

The Design, Operation, and Maintenance of Building Systems, Part I

Technical Advisors:

Howard (Mike) Day

Richard Fanelli, AIA, CFM, IFMA Fellow

Terence M. Watters, PE

The Design, Operation, and Maintenance of Building Systems, Part I

C 2005

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04/21/23 2

Structural Systems& Building Envelope

Michael SemenzinMRSA architects and planners

What’s a structural system??

04/21/23 4

Chapter 4Structural Systems

• Floor & Roof

• Beams & Girders

• Columns & Walls

• Foundation

• Together – they make the frame

Loads

• Dead Loads– Arch. Construction– Mech. Equipment– Utilities– Sprinkler Systems

• Live Loads– People– Furnishings– Machinery– Moveable Walls– Rain, Snow, Ice

• Snow Loads

• Wind Loads– Pressure on windward side– Suction on leeward side– More as you get higher

• Seismic Loads– Earthquakes - shaking

• Vibration Loads– Traffic, heavy trucks– Subway– Airports

• Shock Loads– Suddenly applied– 9/11

4-1

Loads on Buildings

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More Loads

• Load Transfer & Lateral Resistance– Whatever the force, the

goal is to get it into the ground

• Stresses on Frames– Tension – pull apart

– Compression – squish like a grape

– Shear Stress - snap

4-2

Stresses on Members


More on Stress

• Compressive stress compacts material, decreasing the volume. More weight = more compression. Ductile materials (metal, soil, plastic) yield. Brittle materials rupture.

• Aspect ratio (ratio between width & length)– Ratios greater than 2:1 will buckle– Due to “elastic instability”

• Column & Floor to Floor Spacing– Typical column spacing is 20’-35’– Typical floor to floor spacing = 12’-13’– Hotel floor to floor as low as 9’-6”

– More steel = longer span

Fire Resistance

• Hourly ratings (1-4)• Rating = amount of time the element,

component or assembly can contain the fire• Rated ceilings need clips

• Structural system and individual members will need to comply with code required ratings.

Floor Systems

• Steel & Concrete Decks– Cellular Steel– Composite Steel– Open Web Joist– Concrete Slab– Slab On-Grade

• Wood Floor– Deck on Joists– Solid Timber

Building Walls

• Exterior Walls

• Curtain Walls

• Interior Walls

4-3

A Curtain Wall


Steel Frame System

• Load-bearing Wall Construction– Like a house

• Frame Construction– Most highrises

• Long Span Steel Structures– McCormick Place– Bridges

• Combination Steel & Concrete Framing

Advantages of Steel

• High Strength• Uniformity• Elasticity• Permanence• Ductility• Additions to Existing

Structures

• Other advantages– Prefabrication

– Speed

– Weldability

– Toughness

– Reuse

– Recycle

Disadvantages of Steel

• Fireproofing– Encase in concrete or

fireproofing

– Enclose w/ fire rated materials

– Intumescent paint

– Chemically treated water

• Maintenance– Paint

– Rust

– Connections

Concrete Frame Systems

• Reinforced Concrete– Add steel bars for tensile

strength– Poured on-site

• More flexibility• More tedious

– Weathers well

• Precast Concrete– Mass production – less

expensive– Reduced construction time– Better quality control– Take weather out of the

equation– Hard to transport– Connections more difficult– Caulking/maintenance costs– Heavier – needs larger

foundations– Reduced continuity

between structural members

Wood Frame Systems

• Materials– Lumber– Plywood– Laminated Timber

• Disadvantages– Fungus– Termites– Burns easily– Moisture induced

movement

• Systems– Balloon Framing– Platform Framing– Post-&-Beam Framing– Stressed Skin

Construction

Foundations & Soil

• It’s what EVERYTHING sits on– Coarse-grained noncohesive soils– Fine-grained cohesive soils– Organic fibrous soils

• Anything in soil that is or once was alive needs to come out

Soil Concerns

• Moisture content• Permeability• Shearing resistance• Particle size• Liquid limit

• Moisture• Frost• Shifting

– Settlement

– Upheaval

– Sliding

– Liquefaction

Foundation Systems

• Deep Systems– Concrete Piles

• On site• Precast• Augered-in-place• Tapered• Caissons

– Steel Piles• Sheet piles

– Wood Piles• Always wet (tree roots)• Always dry

• Shallow Systems– Spread footings– Mat and Raft systems– Trench footings

• Foundation Materials– Generally reinforced

concrete

4-4

Pile Foundation


Structural Systems Maintenance

• Locate the deterioration• Determine the cause

– Neutralize– Eliminate

• Evaluate the existing strength• Evaluate need for repair• Select & implement repair• Maintaining Foundations

– Look for “tell”– Water is the enemy

• Maintaining Steel– Corrosion– Abrasion– Connections– Fatigue– Impact

• Maintaining Concrete– Cracking– Spalling– Disintegration

• Maintaining Wood– Water, yes water is still the

enemy– Insects are the other enemy

Structural Considerations for Sustainability

• Maximum Solar Access

• Maximize Daylighting

• Reuse of Materials or Structures

• Salvaging Materials

• Recycling Content

• Use Certified Lumber

Chapter 5The Building Envelope

• What is blocks:– Rain, snow, hail, wind,

humidity– Heat & cold– Dirt, soot, pollen, etc.– Bugs and coyotes– Noise– Fire– UV– Bad people

• What it let’s in:– Sunlight– Views– Good people– Natural ventilation

Climate

• Types of Climates– Cold Climates

– Temperate Climates

– Hot/Dry/Arid Climates

– Warm Humid Climates

• Basic Elements– Temperature

– Humidity

– Air Movement

– Precipitation

– Cloud Cover

– Solar Radiation

Design Criteria

• Water Infiltration• Air Infiltration• Loads• Thermal

Expansion/Contraction

• Heat Transfer• Moisture Migration• Sound Attenuation• Building Maintenance• Building Codes

Factors Contributing to Premature Building Decay

• Design deficiencies• Poor material selection• Improper construction• Deferred maintenance• Applied forces• Weight• Vibrations

• Pollution• Vandalism• Air (Oxygen)• Temperature –

extremes• Wind pressure• Water

• Mostly pilot error

WATER IS THE ENEMY

• Gravity– Sloped joints

• Kinetic Energy– Wind driven rain

• Surface Tension– Water moves

horizontally

• Capillary Action– Tiny joints

• Air Currents– Most buildings suck

• Pressure Drops– Mind your weeps

5-1

Six Causes of Water Intrusion and Damage


Air Infiltration

• Sash– “…tore open the

shutter and threw up the sash.”

• Weatherstripping– Gaskets

• Stack Effect– Warm air rises and

rises

• Air Infiltration Tests– ASTM E-283

– 0.06 cf/m or less

Loads

• Wind Loads– Positive pressure windward– Negative pressure leeward– Movement in taller buildings

• Hancock Boston

• Seismic Loads– Shake Rattle and Roll

• Connections & anchors

Heat

• Thermal Expansion & Contraction– Aluminum twice masonry

• Heat Transfer– U-value

• Ability of a system to transmit heat• Inverse of R-value

– Thermal breaks• Curtain connects to structure• Panels connect to framing• Wall assemblies• Within panels themselves• If everything else is sealed

5-2

Solar Energy Transmission Through Clear Glass


5-3

Solar Energy Transmission Through Heat-Absorbing Glass


5-4

Solar Energy Transmission Through Heat-Absorbing Insulated Glass


Moisture Migration

• To Prevent Condensation– Provide a vapor retarder on the interior of the

wall to prevent humid air from entering the wall system

– Insulate internal surfaces– Provide venting for water vapor– Weep system

• Condensation – function of temp & RH

Maintenance & Codes

• Mainly to Maintain– Windows

– Curtain walls

– Sealant systems

– Roof

• Codes for glazing– Daylight

– Natural ventilation

– Safety

– Thermal performance

– Exiting

– Zero clearance lot lines

Curtain Walls

• Metal

• Masonry Veneer

• EIFS

• Stucco

• Wall Panels

5-5

Aluminum Curtain Wall: Top of Vision Light


5-6

Aluminum Curtain Wall: Base of Vision Light


Metal Assemblies

• Selected to Accommodate:– Thermal movement

– Rain/Air penetration

– Structural frame movement

• Mullion Selection:– Size/shape

• Appearance

• strength

– Inside or outside glazing

– Thermal breaks

Masonry Veneer

• Attached directly to masonry back up– Masonry ties or mortar

• Cavity wall– Relieving angles

• At spandrel or floor beam

– Common type of masonry curtain

• Masonry panels– Anchored to studs and sheathing

• Soft joint– For movement and weeps– Flashing Flashing Flashing

EIFS, Stucco & Panels

• EIFS– “Dryvit”

• Stucco– If you can find a large scale example of it call me.

• Wall Panels– Many materials

– 1 story high

– Able to support own weight and transfer loads

Curtain Walls – Vision Area

• Sheet glass– Ordinary glass

• Plate, Annealed or Float

• Heat strengthened glass– Sharp breaks

• Tempered glass– Breaks into little pieces

• Chemically strengthened glass– Tempered with

chemicals• Laminated glass

– Like your car’s windshield

• Plastic glazing– BR glass

Glass Applications

• Monolithic Glass– Ordinary glass

• Plate, Annealed or Float• “Single glazing”

• Insulating Glass– ¼” to ½” between 2 pieces of ordinary glass– Argon or Krypton

• Double Glazing– 1” to 4” between glass– Good for retrofits

Coatings and Tintings

• Reflective– Reduces U/V

– Protects against heat gain and solar glare

– Reduces natural light

• Tinted (Heat absorbing)– Reduces solar glare

– Protects against solar heat gain

– No cold weather protection

– Reduces natural light

• Low-E Coatings– No tinting

– Reduces heat transfer

– Reflects long wave infrared

• Solar Control Films– Retrofits

– Can scratch or peal

• Security Films

Curtain Walls – Nonvision Area

• Stone

• Metal

• Spandrel Glass

• Beware of differences in thermal expansion

Potential Envelope Problems

• Lots of parts & pieces – need regular maintenance• Excess moisture penetration @ joints• Successive freeze/thaw cycles• Exposure to severe weather & pollution• Uneven settlement• Thermal movement of masonry• Unequal expansion/contraction of face materials

and back up

Examples

• Brick veneer on studs– Doesn’t handle heavy winds very well– Mortar cracks / soggy sagging insulation

• Water under the relieving angle– Brick bulges– Must reset the brick

• Joint failure– Flashing– Weeps

Most Common Causes of Glazing Failures

• Failure to properly seal mitre/butt joints• Sash rabbet not clean• Lateral shifting of glass• Failure to properly bed/cushion/center glass• Improper or unsuitable systems• Setting blocks• Out of square• Improper position of spacers or edge blocks• Damage to sash/rabbets/stops• Damage to glass edges• Sealant incompatability

Curtain Wall Fasteners

• Limestone Panels– Stainless steel dowels & anchors– Cushioned w/ sealant– Bolted or welded to the structure– Slotted connections for thermal expansion

• Prefabricated Wall Panels– Continuous supports– Spring metal clips– Weld plates for precast

• Aluminum & Glass Curtain Walls– Stiffness rather than strength governs– Weld anchors to frame

Windows

• Window structure– Jambs, sash, stops, sill & head– Minimize sash movement– Casement/Hopper/Awning – better than Sliding

• Wind Loads• Heat Transfer• Pressure and Infiltration

More Windows

• Heat Transfer– Aluminum is a great heat conductor– Must thermal break with synthetic material– Aluminum must take the wind/gravity loads– Replacing single glazing w/ insulated reduces heat loss by 34%– Double glazing where necessary w/ 1” air gap reduces heat loss by

40%

• Wind Pressure and Infiltration– Air leakage– Balance internal and external pressure– Air infiltration can cause condensation

Windows Materials

• Nonvision Area– Aluminum & vinyl

• Residential• Commercial• Heavy commercial

– Steel• Residential• Standard

intermediate• Heavy intermediate• Heavy custom

– Wood• Residential• Light commercial• Heavy commercial

Aluminum Windows

• Used in all types of construction• Corrosion / hard to refinish / poor heat transfer• Need to be insulated from incompatible materials

– Painting– Caulking– Gasketing

• Anodization– Makes it harder / nonporous– Won’t chip, crack or peel

Vinyl Windows

• PVC (polyvinyl chloride)– Hard, strong & durable– Low thermal transfer– Inexpensive

• Hardware attachment can be a problem• Difficult to refinish• Can be damaged by cold and U/V• Don’t always age well• Vulnerable to fire

Steel Windows

• Great strength allows larger openings

• Thin material = little depth or shadow

• Thermal expansion ½ of aluminum

• Susceptible to oxidation

• Maintenance, maintenance, maintenance

Potential Problems

• Oil based glazing compounds turn brittle over time– Water can get in

• Dirt build up can trap water in weep system• Old weather stripping lets air in• Corrosion

– Fasteners in metal windows need to be made of compatible materials

– Follow the manufacturers directions

Joints

• Joint Structure– Joint size matters

– Cold temperatures stiffen most sealants• Reduces resiliency and ability to absorb stress

– U/V can age some compounds

– Moisture (freeze/thaw) can degrade sealants

– Extreme heat

– Extreme weight

– Zipper gaskets

Joint Materials

• One-part and Two-part Polysulfides• One-part and Two-part Polyurethanes

– One-part (common in building envelopes)• One-part and Two-part Silicones

– One-part (common in building envelopes)– Work horse of construction

• Good adhesions• Good performance in elongation/compression• Attracts and hold dirt

• Acrylics• Acrylic Latexes• Butyls• Oil-based Caulks

Weatherstripping

• Sealing operable sashes and doors• Metal, neoprene tube, brushes• Vinyl and aluminum windows can have in molded in• Selection based on:

– Resistance to air, airborn particles and water– Ability to withstand weather– Compatibility w/ frame and sash materials– Mechanical and physical properties– Resistance to U/V– Ease and continuity of application– Resistance to thermal degradation

Problems with Joints

• Adhesive Failure– Failure to bond with substrate– Substrate was dirty, wet, etc.– Most common

• Cohesive Failure– Failure to bond with self– Movement too great– Add material (bandaid)

• Don’t seal your weeps!!!

Retrofit Projects

• Window Replacement– Appearance– Insulation value– Maintenance costs– Design loads– Building code compliance– Overall energy use– Function changes– Desired installation quality– Day lighting requirements

• Brick Façade Rehab.– Get qualified inspection– Need full set of drawings– Don’t repoint in extreme

weather– Determine when to clean– May need to cover glass– Newer “greener” cleaners

available• Metal Curtain Wall Reseal

– Get qualified inspection– Need full set of drawings– May need to cut out and

recaulk

Envelope Maintenance Program

• 3-Keys– Follow manufacturer’s recommendations– Schedule regular inspections, cleaning, repairs (repairs need to be

done by someone who knows what they are doing)– Keep records

• Window Washing– Typical inside and out

• Scaffolding or automatic– Wash entire exterior surface automatically– Special installations may allow for removal and machine washing

of some parts– Window washers are spot inspectors too

Envelope Simulation

• Heating/cooling load calculations– Peak energy demand and profile

• Alternative systems selection• Energy performance analysis• Energy management and control system design• Regulations/codes/standards compliance checking• Life cycle cost analysis• Quality assurance (commissioning)

Chapter 8Ceilings & Flooring

• Key components in rehabilitating and remodeling, also in new interior build-outs.

• The two largest surfaces you will deal with inside your buildings.

Ceilings

• Generally the upper limit for a space.

• Area between ceiling and deck is the plenum.

• Be careful attaching walls to your ceiling.

• Ceiling panels.

• Ceiling maintenance.– Always follow manufacturer’s recommendations.

Painting reduces acoustics.

Types of Ceiling Systems

• Exposed Grid System

• Concealed Grid or Spline

• Access Tile System

• Snap-in Metal Pan System

• Special Linear Ceiling System

• Integrated Modular System

• Plaster or Drywall System

• Fire Rated System

• Open or Exposed System

Flooring

• Function & Cost

• Appearance & Style

• Durability & Noise

• Comfort & Safety

• Installation & Maintenance

• Weight & Measurement

Types of Flooring

• Resilient• Wood• Hard• Textile

• A Word About Base• Coved at Hard Floor• Straight at Carpet

Floor• Usually Rubber/Vinyl

– Can be Wood

– Can be Tile

– Can be Carpet

Resilient Flooring

• Linoleum• Cork

– Natural Cork

– Waxed Cork

– Resin Reinforced Cork

– Vinyl Cork

• Rubber

• VCT– Vinyl Composition

Tile

• Vinyl Tile– Backed (Laminated)

– Homogeneous

• Sheet Flooring

Wood Flooring

• Strip Flooring– Typically 2 ¼” wide

– Vinyl can now replicate for much less $$$

• Plank Flooring– Wider, more rugged

looking

• Block Flooring

• Installation– Face Nailing– Hidden Nailing– Glue Down

• Finishing Wood Flooring– Sanding– Polyurethane Varnish– Careful w/ Laminated

Wood

Hard Flooring• Concrete

– Finish for sheen

– Acid etch

– Epoxy

• Terrazzo– 2 parts aggregate, 1

part cement

• Magnesite– Misc fillers w/

Magnesium Oxychloride Cement

• Ceramic– Ceramic Mosaic

– Quarry Tile

– Pavers

– Manufactured Tiles

• Brick• Marble & Stone

– Polished

– Honed

– Travertine

• Laminates– Anything you like.

Textile Flooring

• Natural Fibers– Wool

• Great feel

• Stains

– Cotton• Not very durable

• Solution Dyed– Carrot

• Piece Dyed– Radish

• Synthetic Fibers– Acrylic

• Long wearing

– Nylon• Good Stain Resistance

– Olefin (polypropylene)• Suitable for Outdoors

– Polyester• Abrasion Resistance

• Hard to keep clean

– Rayon• Only in cheapest

Carpet Construction

• Woven– Axminster

– Knitting

– Velvet

– Wilton

• Very Durable• Will Unravel at Cut

• Tufted Carpet– Originally jute backed

– More often synthetic

– Urethane backing• Prevents delamination

• Cut Pile• Loop Pile• Tip-Sheared

Carpet Durability

• Face Weight– Amount of yarn oz/sq

yd

• Face Density– # strands/sq yd

• Texture– Can effect durability

• Fiber Type– Nylon

– Olefin

– Polyester

– Acrylic

– Wool

Carpet Installation

• Stretched– Over pad

– Direct

• Glue Down– Direct

– Double Glue Down

– Low VOC adhesives

• Loose Laid– Area Rugs

• Recycling• Carpet Cushion• Carpet Tile

– More $$

– More flexible

– Retrofits

Access Floors

• aka - Raised Floors

• Historically Computer Rooms– Chicago Plenums

• 3” – 18”– ADA Considerations

• 24” or 30” Modules– Laminate– Carpet Tiles

The Design, Operation, and Maintenance of Building Systems, Part I

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Transcript of The Design, Operation, and Maintenance of Building Systems, Part I