OFF SITE CONSTRUCTION Dr. Ruth Collins TrinityHaus [email protected]

OFF SITE CONSTRUCTION

Dr. Ruth CollinsTrinityHaus

[email protected]

OFF SITE CONSTRUCTIONRE-CAP

TYPES OF MODULAR CONSTRUCTION

Modular/POD Method Panelised System Infill Panels Hybrid Construction


RE-CAP WHY CHOOSE EACH METHOD

Modular/POD Method Need for fast construction Regular shapes Need for internal finishes to be done off site



Panelised System Need for Fast Construction Large Open Space Irregular Shapes



Infill Panels Multi-Storey Design

Hybrid Construction Shear core required for services More economical to use more than 1 method Architectural Considerations etc.


LIGHT GAUGE STEEL COMPONENTS

Load Bearing Walls Non-Load Bearing Walls or Partitions Floors Roof Trusses


LIGHT GAUGE STEEL ADVANTAGES

Dry Building Material Not susceptible to moisture or movement

High Tolerances High Precision Production of Profiles Lengths cut within 2mm tolerance

Strength to Weight Ratio very high Environmental Benefits

100% recyclable Flexibility in Size and Design



Hot Dipped Galvanised Cold Rolled Steel Load Bearing Wall Depth, 70mm to 200mm Non-Load Bearing Wall Depth, 70mm to

100mm Floor depth, 200mm to 350mm Roof Trusses, 90mm U-Chord Section



Stud and Track



Stud and Track

h y-yy-y

z-z z-z

z-z z-z

b1

c

b2

c

bp1

cp

hp

bp2

cp

tnom t

y-yy-y

b

h

b

bp

hp

bp

tnom t



Back to Back Stud

y-y

z-z

b

t1nom

t2nom

h hpy-y

z-z

bp

t1

t2

c cp



Boxed Studh

t1nomy-y

z-z

b

b

t2nom

t1y-y

z-z

t2

bp

hp

bp


DESIGN CONSIDERATIONS

Structural Requirements Resist Gravity and Lateral Loads

Other Physical Requirements Depth of Required Insulation Interface Details i.e. type of cladding, amount of

glazing etc Architectural Requirements

Depth of the window reveal Floor spans

Handling and Erection Conditions


STRUCTURAL DESIGN

Gravity Loads Wall studs must be aligned with the floor joists

Lateral Loads Cross Bracing K-Bracing Sheathing Board

Openings Avoid lines of high vertical load Ensure lintel is strong enough to transfer load Provide strength either side of the opening to

transfer load


STRUCTURAL DESIGN (cont...)

Floor to Floor Dimensions i.e. height Floor Zones and Spans

Section size depends on floor span For large spans a lattice floor may be required

Building Height For practical purposes, limit to 4-6 storeys

Progressive Collapse Inter-connectivity between walls and floors


OTHER DESIGN CONSIDERATIONS

Acoustics Fire Resistance Thermal Insulation Durability Environmental Performance


EFFECTIVE WIDTH

Effective width is a function of: Boundary conditions Stress conditions Material Width to thickness ratio etc

Stress distribution vs cross section property Iterative process


EFFECTIVE SECTION PROPERTY

Cee Section

y-y

z-z

z-z

he1

beff

he2

t

beff



Lipped Section

y-y

z-z

z-z

be12

ce1

he1

be11

he2

be21 be22

ce2

t

tred2

tred1



Back to Back Section

be12

ce1

he1

be11

he2

t2

tred

y-y

z-z

z-z

t2



Boxed Section

y-y

z-z

be1 be2

he1

he2


DESIGN EXAMPLE OF LIPPED SECTION

y-y

z-z

z-z

be12

ce1

he1

be11

he2

be21 be22

ce2

ttred2

tred1


FIRE

Requirements vary according to height Protected by layers of plasterboard Staggered layers and importance of detailing Allowed temperature of the steel Cavity Barriers and Connections Testing


ACOUSTICS

Mass Absorption Distance Between Layers Stiffness Resilience Detailing for acoustic breaks and flanking

transmission


ACOUSTICS


ACOUSTICS


THERMAL PERFORMANCE

Thermal performance depends on Thermal performance of the building envelope Ventilation rate and form of construction Air leakages External climate Internal gains


THERMAL PERFORMANCE

Thermal performance of building envelope Depends on position of steel studs Insulation Type Insulation Thickness Insulation Placement Wall Penetrations Thermal Bridging


THERMAL PERFORMANCE

The ‘Warm Frame’ Approach


THERMAL PERFORMANCE

Air Tightness No point in placing lots of insulation if there are lots

of air leaks letting all the hot air escape Comes back to detailing


THERMAL PERFORMANCE

General Guidance Maximise the stud spacing Minimise the stud steel thickness Use ‘warm frame’ construction Minimise cold bridging at openings and joints Provide air tight seal around the building envelope


DURABILITY

Light Gauge Steel protected by Galvanised Coating

Must look at all components regarding durability Insulation materials Claddings Fixings etc…


ENVIRONMENTAL PERFORMANCE

Steel is 100% recyclable Light gauge steel companies use recycled

steel Risk of moisture problems reduced Efficiency of Production – Little Waste High Quality – Little Waste Light weight – Transport more at one time Components can be re-used


USING OFF SITE CONSTRUCTION FOR CONSTRUCTION

INNOVATION?

Documents

OFF SITE CONSTRUCTION Dr. Ruth Collins TrinityHaus [email protected]