BCGCA3004B - Wall Framing

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BCGCA3004B
Construct Wall Framing
Wall Framing
• National Construction Code states that
What does this mean
• NSW law has adopted the National Construction
Code (NCC) as “Building Law”
• The “Building Law” says that the methods outline
in AS 1684.2 will comply with this law.
• So if you follow the methods outlined in AS
1684.2, unless otherwise stated you do not need
any other design assistance e.g. Engineer etc.
AS 1684.2 Scope
Page 9 Section 1.1
AS 1684.2 Scope
Page 9 Section 1.1
This means that this standard only applies the Residential Buildings (Class 1)
or Garages & Carports (Class 10).
Wall Frame Members
• Parts of a frame perform specific functions
- supporting live & dead loads
- resist Racking Forces
- resist Overturning Forces
- resist Sliding Forces
- resist Uplift Forces
-Most members provide a face to accept
linings (this means that member sizes may be
limited)
Live Load
Dead Load
Racking Forces
Wind
Overturning Forces
Wind
Sliding Forces
Wind
Uplift Forces
Wind
What is a Timber Frame
• Structurally Connected Timber Members
• Resist Forces
• Forming a Wall Frame to meet requirements
– Height
– Load
• Roof, Upper Levels etc
– Openings
Timbers Generally Used
• Radiata Pine
• F5
• MGP 10
• Higher Grades for Lintels etc.
• Oregon
• F5
• Hardwood
– Generally only used for Lintels etc.
• Engineered Timbers
– Generally only used for Lintels etc.
Basic Frame Components
Refer page 2 TAFE Guide
Common Stud
• Main Vertical component of the wall
• Transfer Loads from Top Plate to Bottom Plate
• Accept wall finishes
– Straightness will affect the quality
• Accept fittings & Fixtures
– Driers, Shelving etc.
Common Studs
•
•
•
•
Vertical members placed between the plates
The set the wall height
Studs in external frames resist Wind Loads
Generally Stud sizes are 90mm or 70mm wide by
45mm or 35mm in seasoned timbers and
75mm or 100mm wide by 50mm or 38mm in
seasoned timbers.
• Required Stud sizes can be found in AS 1684.2
Supplements (which we will look at Shortly)
Common Studs
• May be Straightened to provide acceptable
wall
• Only 20% of Studs may be Straightened
• Studs at sides of Openings & Supporting
Concentrated Loads shall not be Crippled
Straightening
Refer to Page 59 of AS 1684.2
Confirmation of Learning
• On A4 page supplied draw & label an
Isometric view showing the method of
Crippling Studs
Frame Components
Common Studs
What Consideration For Selection
• Determine Required Grade – Cost v Size, Usually MGP10
• Level – Upper/Single or Lower
• Select Correct Table – For member
• Upper Floor Joist Spacing – Applicable to Double Storey Only
• Upper Floor Load Width – Applicable to Double Storey Only
• Roof Material – Tile/Metal
• Rafter/Truss Spacing – Roof Panel Width
• Stud Spacing – How much of Roof Panel does it carry
• Stud Height – The Taller a stud the less load it can carry
• Roof Load Width – Roof Panel Length
Span Tables supplied – Identify Part
Worked Example Determining Studs
• Refer to Supplied Plans
• Determine minimum sizes of Studs
1. External Walls at rear (Single Storey Section)
•
At Point marked 1
2. External Walls at front (Two Storey Section)
•
•
At Point marked 2 (Lower Level)
At Point marked 3 (Upper Level)
Present this to your trainer for confirmation of
Understanding and recording of completion of the task
Select Stud
To Determine Studs – Answer the Questions
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Determine Required Grade – MGP 10
Upper or Single Level) or Lower Level –
Select Correct Table –
Upper Floor Joist Spacing –
Upper Floor Load Width –
Roof Material –
Rafter/Truss Spacing –
Stud Spacing –
Stud Height –
Roof Load Width -
To Determine Studs – Answer the Questions
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Determine Required Grade – MGP 10
Upper or Single Level) or Lower Level – Single
Select Correct Table –
Upper Floor Joist Spacing –
Upper Floor Load Width –
Roof Material –
Rafter/Truss Spacing –
Stud Spacing –
Stud Height –
Roof Load Width -
To Determine Studs – Answer the Questions
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Determine Required Grade – MGP 10
Upper or Single Level) or Lower Level – Single
Select Correct Table – Table 7 Studs Not Notched
Upper Floor Joist Spacing –
Upper Floor Load Width –
Roof Material –
Rafter/Truss Spacing –
Stud Spacing –
Stud Height –
Roof Load Width -
To Determine Studs – Answer the Questions
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Determine Required Grade – MGP 10
Upper or Single Level) or Lower Level – Single
Select Correct Table – Table 7 Studs Not Notched
Upper Floor Joist Spacing –N/A
Upper Floor Load Width – N/A
Roof Material – Tile Roof
Rafter/Truss Spacing –
Stud Spacing –
Stud Height –
Roof Load Width -
To Determine Studs – Answer the Questions
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Determine Required Grade – MGP 10
Upper or Single Level) or Lower Level – Single
Select Correct Table – Table 7 Studs Not Notched
Upper Floor Joist Spacing –N/A
Upper Floor Load Width – N/A
Roof Material – Tile Roof
Rafter/Truss Spacing – 600mm
Stud Spacing –
Stud Height –
Roof Load Width -
To Determine Studs – Answer the Questions
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•
Determine Required Grade – MGP 10
Upper or Single Level) or Lower Level – Single
Select Correct Table – Table 7 Studs Not Notched
Upper Floor Joist Spacing –N/A
Upper Floor Load Width – N/A
Roof Material – Tile Roof
Rafter/Truss Spacing – 600mm
Stud Spacing – 600mm
Stud Height –
Roof Load Width -
To Determine Studs – Answer the Questions
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Determine Required Grade – MGP 10
Upper or Single Level) or Lower Level – Single
Select Correct Table – Table 7 Studs Not Notched
Upper Floor Joist Spacing –N/A
Upper Floor Load Width – N/A
Roof Material – Tile Roof
Rafter/Truss Spacing – 600mm
Stud Spacing – 600mm
Stud Height – 2700
Roof Load Width -
3 Options
To Determine Studs – Answer the Questions
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Determine Required Grade – MGP 10
Upper or Single Level) or Lower Level – Single Level
Select Correct Table – Table 7 Studs Not Notched
Upper Floor Joist Spacing – N/A
Upper Floor Load Width – N/A
Roof Material – Tile Roof
Rafter/Truss Spacing – 600mm
Stud Spacing – 600mm
Stud Height - 2700
Roof Load Width - 5400
Select the best
For the Situation
70 x 35
Most Suitable 75mm
Most Suitable 90mm
To Determine Studs – Answer the Questions
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Determine Required Grade – MGP 10
Upper or Single Level) or Lower Level –
Select Correct Table –
Roof Material –
Upper Floor Joist Spacing –
Upper Floor Load Width –
Rafter/Truss Spacing –
Stud Spacing –
Stud Height –
Roof Load Width -
To Determine Studs – Answer the Questions
•
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•
Determine Required Grade – MGP 10
Upper or Single Level) or Lower Level – Lower Level
Select Correct Table –
Roof Material –
Upper Floor Joist Spacing –
Upper Floor Load Width –
Rafter/Truss Spacing –
Stud Spacing –
Stud Height –
Roof Load Width -
To Determine Studs – Answer the Questions
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Determine Required Grade – MGP 10
Upper or Single Level) or Lower Level – Single
Select Correct Table – Table 36 Studs Not Notched
Roof Material –
Upper Floor Joist Spacing –
Upper Floor Load Width –
Rafter/Truss Spacing –
Stud Spacing –
Stud Height –
Roof Load Width -
To Determine Studs – Answer the Questions
•
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Determine Required Grade – MGP 10
Upper or Single Level) or Lower Level – Single
Select Correct Table – Table 7 Studs Not Notched
Roof Material – Tile Roof
Upper Floor Joist Spacing –N/A
Upper Floor Load Width – N/A
Rafter/Truss Spacing –
Stud Spacing –
Stud Height –
Roof Load Width -
To Determine Studs – Answer the Questions
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•
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Determine Required Grade – MGP 10
Upper or Single Level) or Lower Level – Single
Select Correct Table – Table 7 Studs Not Notched
Roof Material – Tile Roof
Upper Floor Joist Spacing – 600mm
Upper Floor Load Width – N/A
Rafter/Truss Spacing –
Stud Spacing –
Stud Height –
Roof Load Width -
To Determine Studs – Answer the Questions
•
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•
•
Determine Required Grade – MGP 10
Upper or Single Level) or Lower Level – Single
Select Correct Table – Table 7 Studs Not Notched
Roof Material – Tile Roof
Upper Floor Joist Spacing – 600mm
Upper Floor Load Width – 3000mm
Rafter/Truss Spacing –
Stud Spacing –
Stud Height –
Roof Load Width -
To Determine Studs – Answer the Questions
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Determine Required Grade – MGP 10
Upper or Single Level) or Lower Level – Single
Select Correct Table – Table 7 Studs Not Notched
Roof Material – Tile Roof
Upper Floor Joist Spacing – 600mm
Upper Floor Load Width – 3000mm
Rafter/Truss Spacing – N/A
Stud Spacing –
Stud Height –
Roof Load Width -
To Determine Studs – Answer the Questions
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•
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Determine Required Grade – MGP 10
Upper or Single Level) or Lower Level – Single
Select Correct Table – Table 7 Studs Not Notched
Roof Material – Tile Roof
Upper Floor Joist Spacing – 600mm
Upper Floor Load Width – 3000mm
Rafter/Truss Spacing – N/A
Stud Spacing – 600mm
Stud Height –
Roof Load Width -
To Determine Studs – Answer the Questions
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Determine Required Grade – MGP 10
Upper or Single Level) or Lower Level – Single
Select Correct Table – Table 7 Studs Not Notched
Roof Material – Tile Roof
Upper Floor Joist Spacing – 600mm
Upper Floor Load Width – 3000mm
Rafter/Truss Spacing – N/A
Stud Spacing – 600mm
Stud Height – 2700mm
Roof Load Width -
To Determine Studs – Answer the Questions
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Determine Required Grade – MGP 10
Upper or Single Level) or Lower Level – Single Level
Select Correct Table – Table 7 Studs Not Notched
Upper Floor Joist Spacing – N/A
Upper Floor Load Width – N/A
Roof Material – Tile Roof
Rafter/Truss Spacing – 600mm
Stud Spacing – 600mm
Stud Height - 2700
Roof Load Width - 3800
Most Suitable 75mm
Most Suitable 90mm
Confirmation of Learning
• Refer to Supplied Plans
• Trainer to Provide
– Rafter/Truss Spacing
– Stud Spacing
– Roof Load Width = ½ Span ÷ Cos (Pitch°)
• Determine minimum sizes of Studs
1. External Walls at rear (Single Storey Section)
•
At Point marked 1
2. External Walls at front (Two Storey Section)
•
•
At Point marked 2 (Lower Level)
At Point marked 3 (Upper Level)
Basic Frame Components
Refer page 2 TAFE Guide
Jamb Studs
• Additional Studs placed at sides of Openings
in walls carrying structural loads
• Accommodate extra loads imposed by Lintels
Jamb Studs - Notching
Jamb Studs - Housing
Why Bother
2/75 x 3.8mm is more than
enough
Housings not allowed in Load Bearing Walls
Frame Components
Jamb Studs
What Consideration For Selection
• Determine Required Grade – Cost v Size.
• Upper or Single Level) or Lower Level – Is it taking 1st Floor Load.
• Select Correct Table – Common, Jamb or Concentrated Loads Studs.
• Upper Floor Load Width – Floor Load Panel Length (Only Applies to 2 Storey).
• Roof Material – Tile or Metal Roof
• Roof Load Width – Roof Load Panel Length
• Lintel Span – Opening being Spanned
• Stud Height – Taller Stud has less ability to carry load.
Span Tables supplied – Identify Part
Frame Components
Jamb Studs
What Consideration For Selection
• Determine Required Grade – MGP10
• Upper or Single Level) or Lower Level – Single
• Select Correct Table – Table 11
• Upper Floor Load Width – N/A
• Roof Material – Tile
• Roof Load Width –
• Lintel Span –
• Stud Height –
Span Tables supplied – Identify Part
Frame Components
Jamb Studs
What Consideration For Selection
• Determine Required Grade – MGP10
• Upper or Single Level) or Lower Level – Single
• Select Correct Table – Table 11
• Upper Floor Load Width – N/A
• Roof Material – Tile
• Roof Load Width – 5400
• Lintel Span –
• Stud Height –
Span Tables supplied – Identify Part
Frame Components
Jamb Studs
What Consideration For Selection
• Determine Required Grade – MGP10
• Upper or Single Level) or Lower Level – Single
• Select Correct Table – Table 11
• Upper Floor Load Width – N/A
• Roof Material – Tile
• Roof Load Width – 5400
• Stud Height – 2700
• Lintel Span –
Span Tables supplied – Identify Part
Frame Components
Jamb Studs
What Consideration For Selection
• Determine Required Grade – MGP10
• Upper or Single Level) or Lower Level – Single
• Select Correct Table – Table 11
• Upper Floor Load Width – N/A
• Roof Material – Tile
• Roof Load Width – 5400
• Stud Height – 2700
• Lintel Span – 1900
Span Tables supplied – Identify Part
Most Suitable for 75mm
Most Suitable for 90mm
Studs for Concentrated Loads
Studs for Concentrated Loads
See Page 67 - AS 1684.2 - 2006
• Point Load from Beam etc. that gathers load
from other structural members
Studs for Concentrated Loads
See Page 67 - AS 1684.2 - 2006
• Point Load from Beam etc. that gathers load
from other structural members
• Beams etc. > 3000mm that take loads from
– Strutting Beams
– Roof Struts
– Girder Trusses or
– Hanging Beams
Frame Components
Studs Supporting Concentrated Loads`
What Consideration For Selection
• Determine Required Grade – Cost v Size.
• Upper or Single Level) or Lower Level – Is it taking 1st Floor Load.
• Select Correct Table – Common, Jamb or Concentrated Loads Studs.
• Upper Floor Load Width – Floor Load Panel Length (Only Applies to 2 Storey).
• Roof Material – Tile or Metal Roof
• Stud Height – Taller Stud has less ability to carry load.
• Roof Area Supported – Roof Load Imposed
Span Tables supplied – Identify Part
Frame Components
Studs Supporting Concentrated Loads`
What Consideration For Selection
• Determine Required Grade – MGP 10
• Upper or Single Level) or Lower Level – Single
• Select Correct Table – Table 9
• Upper Floor Load Width – N/A
• Roof Material – Tile
• Stud Height –
• Roof Area Supported –
Span Tables supplied – Identify Part
Frame Components
Studs Supporting Concentrated Loads`
What Consideration For Selection
• Determine Required Grade – MGP 10
• Upper or Single Level) or Lower Level – Single
• Select Correct Table – Table 9
• Upper Floor Load Width – N/A
• Roof Material – Tile
• Stud Height – 2700
• Roof Area Supported –
Span Tables supplied – Identify Part
Frame Components
Studs Supporting Concentrated Loads`
What Consideration For Selection
• Determine Required Grade – MGP 10
• Upper or Single Level) or Lower Level – Single
• Select Correct Table – Table 9
• Upper Floor Load Width – N/A
• Roof Material – Tile
• Stud Height – 2700
• Roof Area Supported – (4.150 x 5.400) ÷ 4 = 5.6m2
= 4.150
= 5.400
Note – Dimensions are in metres
Therefore a 70 x 45 is sufficient
Studs supporting concentrated Loads
• It is important that you develop the ability to
recognise the location of Concentrated Loads
• This will allow you to install the required studs
while manufacturing the frames
Discuss Concept of Pattern Stud
• Common Studs
• Lintel Positions
• Trimmers
Basic Frame Components
Refer page 2 TAFE Guide
Frame Components
Bottom Plate
•Horizontal member that form the bottom of the frame.
•Bottom plate must run full length of wall, except at openings (cl 6.2.2)
•Bottom plates are joined with butt joints with fixing near the joint
•Joints must be fully supported
Frame Components
Bottom Plate
•Horizontal member that form the bottom of the frame.
•Bottom plate must run full length of wall, except at openings (cl 6.2.2)
•Bottom plates are joined with butt joints with fixing near the joint
•Joints must be fully supported
•Where the Bottom Plate Supports a concentrated Load or Jamb Studs
to openings > 1200, the bottom plate must be fully supported
Frame Components
Bottom Plate
Sizing
•Bottom plate sizing is dependent on its span
•If it is fully supported (e.g. Concrete Slab) only nominal 35mm
thickness required for any structural grade (cl 6.3.3)
•Items to consider when determining the size of Bottom Plate are
listed in the span tables where you make the selections. (page 1 & 2
of Handout)
1. Timber Grade – Strength of Timber
2. Joist Spacing – Means greater span
3. Loading – Load that is to be disturbed through structure
Is it a tiled roof, Is it the lower level of a 2 storey building
4. Rafter/Joist Spacing – More load concentrated at studs once
distributed.
Span Tables supplied – Identify Part
Design Parameters for Bottom Plate
Worked Example
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Roof Material
Rafter / Truss Spacing
Joist Spacing
Roof Load Width
Sheet Roof
600mm
450mm
6000mm
Worked Example
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Roof Material
Rafter / Truss Spacing
Joist Spacing
Roof Load Width
Sheet Roof
600mm
450mm
6000mm
Worked Example
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Roof Material
Rafter / Truss Spacing
Joist Spacing
Roof Load Width
Sheet Roof
600mm
450mm
6000mm
Worked Example
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•
Roof Material
Rafter / Truss Spacing
Joist Spacing
Roof Load Width
Sheet Roof
600mm
450mm
6000mm
Select most
Suitable
Worked Example
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•
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•
Roof Material
Rafter / Truss Spacing
Joist Spacing
Roof Load Width
Sheet Roof
600mm
450mm
6000mm
v
70 x 45
Or
90 x 45
Confirmation of Learning
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Determine Minimum Member Size Based on Following Data
(Conventional Floor System)
Roof Load Width
Truss Spacing
Joist Spacing
Stud
Roof Material
4100mm
600mm
450mm
90mm Wide
Tile
Minimum Size ______________________
Determine Minimum Member Size Based on Following Data
(Concrete Slab)
Roof Load Width
Truss Spacing
Joist Spacing
Stud
Roof Material
4100mm
600mm
N/A
70mm Wide
Tile
Minimum Size ______________________
Confirmation of Learning - Answer
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Determine Minimum Member Size Based on Following Data
(Conventional Floor System)
Roof Load Width
Truss Spacing
Joist Spacing
Stud
Roof Material
4100mm
600mm
600mm
90mm Wide
Tile
Minimum Size
2/ 70 x 45
Determine Minimum Member Size Based on Following Data
(Concrete Slab)
Roof Load Width
Truss Spacing
Joist Spacing
Stud
Roof Material
4100mm
600mm
N/A
70mm Wide
Tile
Minimum Size
70 x 35 (Nominal as Fully Supported)
Basic Frame Components
Refer page 2 TAFE Guide
Top Plate
• An Important Structural Member
• Provides Lateral tie to the Building
Top Plate
• An Important Structural Member
• Provides Lateral tie to the Building
• Provides a transition point for the connection
of Roofing Members and distribution of loads
• A Component of the Bracing System
Top Plate
• An Important Structural Member
• Provides Lateral tie to the Building
• Provides a transition point for the connection
of Roofing Members and distribution of loads
• A Component of the Bracing System
• A component of the uplift restraint system
Top Plate
• To Plates must run full length of the wall
• Top Plate must run over openings
• Concentrated Loads must be Fully Supported
Frame Components
To Plate
Sizing
•Top plate sizing is dependent (See pages 3 to 6 of Handout)
•Positioning of Rafter/Truss (See next Slide)
•Upper or Lower Level (Pages 3 & 4 v Pages 5 & 6)
1. Timber Grade – Strength of Timber
2. Roof Material – Tile v Metal
3. Rafter/Truss Spacing – How & Where the Load is applied
4. Stud Spacing – How much bending will be caused by Rafters
5. Roof Load Width - How wide is the Building (see next slide)
Span Tables supplied – Identify Part
Frame Components
To Plate
Sizing
•Top plate sizing is dependent (See pages 3 to 6 of Handout)
(Pages 3 & 4 v Pages 5 & 6)
1. Timber Grade – Strength of Timber
2. Location – Single Level , Upper Level or Lower of 2 Storey
3. Roof Material – Tile v Metal
4. Rafter/Truss Spacing – How & Where the Load is applied
5. Tie Down Spacing – Bending imposed on Top Plate by Uplift
6. Stud Spacing – How much bending will be caused by Rafters
7. Roof Load Width - How wide is the Building (see next slide)
Worked Example
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Roof Material
Location
Rafter / Truss Spacing
Tie Down Spacing
Stud Spacing
Roof Load Width
Sheet Roof
Single Storey
600mm
600mm
450mm
6000mm
Worked Example
•
•
•
•
•
•
Roof Material
Location
Rafter / Truss Spacing
Tie Down Spacing
Stud Spacing
Roof Load Width
Sheet Roof
Single Storey
600mm
600mm
450mm
6000mm
Worked Example
•
•
•
•
•
•
Roof Material
Location
Rafter / Truss Spacing
Tie Down Spacing
Stud Spacing
Roof Load Width
Sheet Roof
Single Storey
600mm
600mm
450mm
6000mm
Worked Example
•
•
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•
•
Roof Material
Location
Rafter / Truss Spacing
Tie Down Spacing
Stud Spacing
Roof Load Width
Sheet Roof
Single Storey
600mm
600mm
450mm
6000mm
Worked Example
•
•
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•
Roof Material
Location
Rafter / Truss Spacing
Tie Down Spacing
Stud Spacing
Roof Load Width
Sheet Roof
Single Storey
600mm
600mm
450mm
6000mm
Worked Example
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•
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•
Roof Material
Location
Rafter / Truss Spacing
Tie Down Spacing
Stud Spacing
Roof Load Width
Sheet Roof
Single Storey
600mm
0
450mm
6000mm
70 x 45
90 x 45
Confirmation of Learning
• Determine Minimum Member Size Based on
Following Data
•
•
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•
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•
•
Roof Material
Location
Rafter / Truss Spacing
Tie Down Spacing
Stud Spacing
Roof Load Width
Wall Frame Width
Sheet Roof
Single Storey
600mm
0
600mm
5500mm
70mm
• Minimum Size ______________________
Confirmation of Learning - Answer
• Determine Minimum Member Size Based on
Following Data
•
•
•
•
•
•
•
Roof Material
Location
Rafter / Truss Spacing
Tie Down Spacing
Stud Spacing
Roof Load Width
Wall Frame Width
• Minimum Size
Sheet Roof
Single Storey
600mm
0
600mm
5500mm
70mm
70 x 45
Undersize Top Plate
Undersize Top
Plate
Plates
• Seasoned timbers are dressed therefore
trenching not required
• Rough Sawn Timbers such as Oregon,
Hardwood require trenching.
• Housing of plates for studs provides a constant
thickness
• Trenching keeps Top & Bottom plates parallel
• Restrains Unseasoned Studs from twisting
• Trenching usually
appox 10 mm
• Trenching depth is
not critical but what
is left on is.
• Top Plates fully
supported on
masonary walls will
be sized based on a
300mm spacing
Joining of Plates
• Where plates are butt jointed they may be
joined using a connector plate.
Joining of Plates
• Plates may be Scarfed or Lapped jointed.
• Theses are time consuming and rarely used
Calculate Plate Lengths
• During Fabrication Top & Bottom Plates are
the same length
• Plates should be as long as possible
• Consider manpower available to stand frames
• Remember Top Plate must be continuous
Roof Load Width
AS 1684 - Definition
Roof Load Width
Why is it an Important Consideration?
Roof Load Width
Why is it an Important Consideration?
Compare if
Y= 5m & b = 0.6m
Roof Load Width
Why is it an Important Consideration?
The Top Plate in the Top example is taking more load
B = 5 + 5 + 0.6
2
= 5.6m
Compare if
Y= 5m & b = 0.6m
B = 5 + 0.6
6
= 1.433m
Uplift
• Uplift is a complex item and dealt with at Cert
IV level
• Generally in Sydney for a Tile Roof it is not a
consideration (See next slide) except for;
– Ocean Front
– Top of a Hill
– Isolated Buildings with no wind shielding
Basic Frame Components
Refer page 2 TAFE Guide
Lintels
• Also referred to as a Head when it is not
supporting Structural Loads
• Horizontal Load Bearing Member between Studs
• Purpose is to transfer structural loads that are
above an opening to load bearing studs
• May be made of many materials
- Timber
- Engineered Timbers - LVL’s, I Beams
- Structural Steel or Cold Rolled Steel Sections
Lintels – Installation Requirements
AS 1684 Figure 6.9 page 64
Lintels – Installation Requirements
AS 1684 Figure 6.9 page 64
Lintels – Installation Requirements
AS 1684 Figure 6.9 page 64
Lintels – Installation Requirements
AS 1684 Figure 6.9 page 64
From experience this is my preferred method as if there is
A change in size or height, it does not require a major alteration
It is a simple change of the infill head.
Lintels – Requirement for Top Plate
Top Plate must be
Continuous
The Top Plate CANNOT be cut
To fit a Lintel
Frame Components
Lintel
Sizing
•Lintel sizing is dependent (See pages 9 & 10 of Handout)
1.
2.
3.
4.
5.
6.
7.
Timber Grade – Strength of Timber
Roof Material – Tile v Metal
Location – Upper,Single or Lower Level of 2 Storey
Floor Load Width– Applicable to Lowers Storey of 2 Storey Only
Roof Load Width - How wide is the Building
Rafter Truss Spacing – Loading on Beam
Lintel Span – Required Span
Span Tables supplied – Identify Part
Worked Example
Worked Example
1.
2.
3.
4.
5.
6.
7.
Timber Grade – MGP10
Roof Material – Tile
Location – Single Level
Floor Load Width–
Roof Load Width –
Rafter Truss Spacing –
Lintel Span –
Worked Example
1.
2.
3.
4.
5.
6.
7.
Timber Grade – MGP10
Roof Material – Tile
Location – Single Level
Floor Load Width – N/A
Roof Load Width – 3500mm
Rafter Truss Spacing –
Lintel Span –
Worked Example
1.
2.
3.
4.
5.
6.
7.
Timber Grade – MGP10
Roof Material – Tile
Location – Single Level
Floor Load Width – N/A
Roof Load Width – 3500mm
Rafter Truss Spacing – 600mm
Lintel Span –
Worked Example
1.
2.
3.
4.
5.
6.
7.
Timber Grade – MGP10
Roof Material – Tile
Location – Single Level
Floor Load Width – N/A
Roof Load Width – 3500mm
Rafter Truss Spacing – 600mm
Lintel Span – 2100mm
6. Noggins
6. Noggins
• Stop Studs from Twisting, Cupping etc
• Assist Studs to take load – prevent buckling
under load
• Form Part of Bracing System
6.Noggins
• Walls > 1350mm in height must have
noggins
• Max Spacing between rows = 1350mm
• No Stress grading required
• Min 25mm Thick
• Noggins may be offset 2 x Thickness to
allow for ease of Installation
• Min width = Wall Thickness – 25mm
Confirmation of Learning
1. How many Rows of Noggins are required for
following wall heights.
1. 2550
2. 3000
3. 3800
2. Is a 70 x 35 Noggin suitable for a 90mm Wall
Frame
Bracing
6. Bracing
• Member that prevents distortion of frame by
– Racking Forces
You must determine
Wind load on Building
Bracing
• There are many materials that can be used to
Brace a wall frame.
• These generally form part of a system.
• See page 4 of TAFE Notes
Diagonal Timber Bracing
• Rarely Used Today.
Diamond Bracing
• Not Mentioned in AS 1684.2.
• Must be Considered an Alternative Solution.
• Would require an Engineer to Certify.
Perforated Metal Angle
Where there a 2 in a wall,
They should oppose each other
Hoop Iron Cross Bracing
A very good and efficient method and should be 1st choice
Hoop Iron Cross Bracing
Tensioning should be done during the hottest part of the day
Hoop Iron Cross Bracing
Final Nailing off should be done as late as possible
Leave temporary bracing as long as possible
Sheet Bracing
• Plywood or Hardboard (Masonite)
6. Bracing
• Member that prevents distortion of frame by
– Racking Forces
– Section 8 of Standard
(a) Determine Wind Classification
Limitations of Classification
Same Limitations AS 1684.2
(a) Determine Wind Classification
• AS 4055 Outline the Process to Determine
1.
2.
3.
4.
Geographic Wind Speed
Terrain Category
Topographic Class
Shielding
(a) Determine Wind Classification
• AS 4055 Outline the Process to Determine
1.
2.
3.
4.
Geographic Wind Region
Terrain Category
Topographic Class
Shielding
1.Geographic Wind Region
Exercise
•
What Region are the following Cities or towns located in
– Sydney
______________
– Brisbane
______________
– Melbourne
______________
– Darwin
______________
– Perth
______________
– Grafton (NSW)
______________
– Townsville (Qld)
______________
– Alice Springs (NT)
______________
– Perisher Valley (NSW)
______________
– Launceston (TAS)
______________
– Port Hedland (WA)
______________
Exercise - Answer
•
What Region are the following Cities or towns located in
– Sydney
A
– Brisbane
B
– Melbourne
A
– Darwin
C
– Perth
A
– Grafton (NSW)
B
– Townsville (Qld)
C
– Alice Springs (NT)
A
– Perisher Valley (NSW)
A
– Launceston (TAS)
A
– Port Hedland (WA)
D
•
(a) Determine Wind Classification
• AS 4055 Outline the Process to Determine
1.
2.
3.
4.
Geographic Wind Speed
Terrain Category
Topographic Class
Shielding
2.Terain Category
2.Terain Category
Exercise
• Determine The Follow Terrain Categories
1.
An Isolated House at Woomera with no significant Topographical features for
15km in all directions.
Classification
2.
A House at Bronte located on the Ocean Front.
Classification
3.
_________________
House Build adjacent to Richmond Air force Base
Classification
4.
_________________
_________________
A house in Alexandria (NSW)
Classification
_________________
Exercise - Answer
• Determine The Follow Terrain Categories
1.
An Isolated House at Woomera with no significant Topographical features for
15km in all directions.
Classification
2.
A House at Bronte located on the Ocean Front.
Classification
3.
TC2
House Build adjacent to Richmond Air force Base
Classification
4.
TC1
TC2
A house in Alexandria (NSW)
Classification
TC3
(a) Determine Wind Classification
• AS 4055 Outline the Process to Determine
1.
2.
3.
4.
Geographic Wind Speed
Terrain Category
Topographic Class
Shielding
3. Topographic Class
Topographic class determines the effect of
wind on a house considering its location on a,
• hill,
• ridge or escarpment and
• the height and average slope of the hill, ridge
or escarpment.
3. Topographic Class
Where average slope is
Greater than 1 in 20 is the
Start of the “Hill” .
3. Topographic Class
Height of Hill.
3. Topographic Class
Height of Hill.
Note Parameter for Escarpment
3.Topographic Class
AS 4055 - 2006
Topography for Hills Explained
Determine Average Slope
The average slope of a hill, ridge or escarpment (φa) shall be the slope measured by
averaging the steepest slope and the least slope through the top half of the hill, ridge or
escarpment.
AS 4055 - Table 2.3 Row 1
Average Slope < 1 in 10
T1
T1
All Heights
T1
AS 4055 - Table 2.3 Row 2
Average Slope < 1 in 10
& > 1 in 7.5
T2*
T1
T1
*Less than 20m all T1
AS 4055 - Table 2.3 Row 3
Average Slope < 1 in 7.5
& > 1 in 5
*H > 30 T3
*H ≤ 30 T2
T1
T1
*Less than 9m all T1
AS 4055 - Table 2.3 Row 4
H > 30 T4
H ≤ 30 T3
T2
T1
H
Average Slope < 1 in 5
& > 1 in 3
AS 4055 - Table 2.3 Row 5
Average Slope > 1 in 3
T2
T1
H
H > 30 T5
H ≤ 30 T4
Topography for Escarpments Explained
3.Topographic Class
AS 4055 - 2006
Determine Average Slope
The average slope of a hill, ridge or escarpment (φa) shall be the slope measured by
averaging the steepest slope and the least slope through the top half of the hill, ridge or
escarpment.
AS 4055 - Table 2.3 Row 1
T1
T1
T1
T1
All Heights
Average Slope < 1 in 10
AS 4055 - Table 2.3 Row 2
Average Slope < 1 in 10
& > 1 in 7.5
*T2
T1
T1
T1
*Less than 20m all T1
AS 4055 - Table 2.3 Row 3
Average Slope < 1 in 7.5
& > 1 in 5
*H > 30 T3
*H ≤ 30 T2
T1
T1
T1
*Less than 9m all T1
AS 4055 - Table 2.3 Row 4
Average Slope < 1 in 5
& > 1 in 3
T2
T1
T2
H
H > 30 T4
H ≤ 30 T3
AS 4055 - Table 2.3 Row 5
Average Slope > 1 in 3
T2
T1
T3
H
H > 30 T5
H ≤ 30 T4
Worked Example
For Our Purposes in this course we will always use T1
You will go into more detail in the CERT IV Course
(a) Determine Wind Classification
• AS 4055 Outline the Process to Determine
1.
2.
3.
4.
Geographic Wind Speed
Terrain Category
Topographic Class
Shielding
4.Shielding
• The affect of local obstructions on wind flow
• The 5 year likely impact must be considered
– Growth of Trees etc.
– Proposed Developments etc.
• Classes
– Full Shielding (FS)
– Partial Shielding (PS)
– No Shielding (NS)
Full Shielding (FS)
1. Surrounded by 2 Rows of Houses
2. Heavily Wooded Areas (Zones A & B Only)
3. Typical Suburb consisting of 10 houses per Ha
4. Roads or Parks less than 100m wide are
ignored
Partial Shielding (PS)
• 2.5 Houses, Trees, Sheds etc. per Ha
• In Regions C & D heavily wooded areas
No Shielding (NS)
• No Permanent Obstructions
• Less than 2.5 obstructions per Ha
• First 2 Rows abutting Open Parkland, Open
Water, Airfield etc.
Worked Examples
Wind Classification
Worked Example
TAFE
UNI
Randwick Town Centre
Worked Example
• Geographic Wind Region Region A
Worked Example
• Geographic Wind Region
• Topography
House is not
On a hill
Region A
T1
Worked Example
• Geographic Wind Region
• Topography
• Shielding
Shielded by 2 Rows of Houses
Region A
T1
FS
Worked Example
•
•
•
•
Geographic Wind Region
Topography
Shielding
Terrain Category
Region A
T1
FS
TC 3
Worked Example
•
•
•
•
Geographic Wind Region
Topography
Shielding
Terrain Category
Region A
T1
FS
TC 3
Worked Example
•
•
•
•
Geographic Wind Region
Topography
Shielding
Terrain Category
Region A
T1
FS
TC 3
Worked Example
•
•
•
•
Geographic Wind Region
Topography
Shielding
Terrain Category
Region A
T1
FS
TC 3
Worked Example
•
•
•
•
Geographic Wind Region
Topography
Shielding
Terrain Category
Wind Category is N1
Region A
T1
FS
TC 3
Worked Example
Bronte Ocean Front
Worked Example
• Geographic Wind Region
Region A
Worked Example
• Geographic Wind Region
• Topography
House is located on top
Of 30m escarpment
Region A
T5
Worked Example
• Geographic Wind Region
• Topography
• Shielding
Region A
T5
NS
No Shielding on Ocean Side – You must always use worst case example
Worked Example
•
•
•
•
Geographic Wind Region
Topography
Shielding
Terrain Category
Region A
T5
NS
TC1
Worked Example
•
•
•
•
Geographic Wind Region
Topography
Shielding
Terrain Category
Region A
T5
NS
TC1
Worked Example
•
•
•
•
•
Geographic Wind Region
Topography
Shielding
Terrain Category
Region A
T5
NS
TC1
Worked Example
•
•
•
•
•
Geographic Wind Region
Topography
Shielding
Terrain Category
Region A
T5
NS
TC1
Worked Example
•
•
•
•
Geographic Wind Region
Topography
Shielding
Terrain Category
Wind Category = N5
Region A
T5
NS
TC1
Determine Wind Pressure
• Determined by;
– Wind Classification
– Tables 8.1 to 8.5 AS 1684.2
– Is dependant on the shape of the Building
Is it a Gable or Hip or a more Complex shape? – Explained in Next Slides
Table 8.2
Area of Elevation
h = ½ height of the wall (half of
the floor to ceiling height).
For wind direction 2, the pressure
on the gable end is determined
from Table 8.1
Table 8.1
Table 8.2
Table 8.2
The total of racking forces is the
sum of the forces calculated for
each section.
Eaves < 1m2 can be ignored.
Table 8.2
pressure on the hip section of the
elevation is determined from
Table 8.2.
Area of Elevation
11000
15000
7000
You must determine
Area of each part of the
elevation Of the Building.
8000
6000
5000
Area of Elevation
Wind Direction 1 has 2 Shapes
1.1 = 14m2
1.2 = 16m2
2
1
2
1
Wind Direction 2 has 2 Shapes
14m2
1.1 =
1.2 = 14m2
(d) Calculating Racking Force
• Formula
• Area of Elevation x Wind Pressure
• Required Data
• Pitch = 30°
(d) Calculating Racking Force
Racking Force = Area x Wind Pressue
Wind Direction 1 has 2 Shapes
1.1 = 14m2 x Wind Pressure ?
1.2 = 16m2
2
1
6000
5000
2
1
Wind Direction 2 has 2 Shapes
14m2
1.1 =
1.2 = 14m2
Wind Pressure Direction 1.1
(d) Calculating Racking Force
Racking Force = Area x Wind Pressue
Wind Direction 1 has 2 Shapes
1.1 = 14m2 x 0.75 = 10.5
1.2 = 16m2 x Wind Pressure ?
2
1
6000
5000
2
1
Wind Direction 2 has 2 Shapes
14m2
1.1 =
1.2 = 14m2
Wind Pressure Direction 1.2
(d) Calculating Racking Force
Racking Force = Area x Wind Pressue
Wind Direction 1 has 2 Shapes
1.1 = 14m2 x 0.75 = 10.5
1.2 = 16m2 x 0.74 = 11.84
2
1
6000
5000
2
1
Total Racking Force = 22.34
Wind Direction 2 has 2 Shapes
14m2 x Wind
1.1 =
1.2 = 14m2
Pressure ?
8000
7000
Important Note
Which Wind Pressure to Use ?
8 000
Wind N2
Pitch 25°
15 000
As shape is the same from both directions
We use the same Table (8.2)
Pressure = 0.73 in Both Directions
Important Note
Which Wind Pressure to Use ?
8 000
Wind N2
Pitch 25°
Table 8.1
Table 8.2
15 000
As shape is different in each elevation we must determine individually for each direction
And use WORST case.
Pressure = 0.92
Pressure = 0.71
Important Note
Which Wind Pressure to Use ?
Wind N2
8 000
The Gable End will ALWAYS have the highest pressure
Pitch 25°
Table 8.1
= 0.92
Table 8.2
= 0.71
15 000
As the worst case is the Gable End, we must use the wind Pressure from Table 8.1 = 0.92
Pressure = 0.71
(d) Calculating Racking Force - Revisited
Racking Force = Area x Wind Pressue
Wind Direction 1 has 2 Shapes
1.1 = 14m2 x 0.75 = 10.5
1.2 = 16m2 x 0.74 = 11.84
2
1
6000
5000
2
1
Total Racking Force = 22.34
Wind Direction 2 has 2 Shapes
14m2 x Wind
1.1 =
1.2 = 14m2
Pressure ?
Wind Pressure Direction 1.2
You must
use this
table as it is
a Gable End
(d) Calculating Racking Force
Racking Force = Area x Wind Pressue
Wind Direction 1 has 2 Shapes
1.1 = 14m2 x 0.75 = 10.5
1.2 = 16m2 x 0.74 = 11.84
2
1
6000
5000
2
1
Total Racking Force = 22.34
Wind Direction 2 has 2 Shapes
14m2 x 0.92
2.1 =
= 12.88
2.2 = 14m2 x Wind Pressure ?
8000
7000
Wind Pressure Direction 2.2
(d) Calculating Racking Force
Racking Force = Area x Wind Pressue
Wind Direction 1 has 2 Shapes
1.1 = 14m2 x 0.75 = 10.5
1.2 = 16m2 x 0.74 = 11.84
2
1
6000
5000
2
1
Total Racking Force = 22.34
Wind Direction 2 has 2 Shapes
2.1 = 14m2 x 0.92 = 12.88
2.2 = 14m2 x 0.72 = 10.08
8000
Total Racking Force = 22.96
7000
Before we do this lets see what (f) says
Before we do this lets see what (f) says
Clause 8.3.6.6
We must start placing Bracing at,
1. External Walls &
2. At Corners
Before we do this lets see what (f) says
Clause 8.3.6.7
Single or Upper Level Bracing
Max Spacing is 9m for N2 &
N2 Wind Classification
For N3 & above refer Tables
Before we do this lets see what (f) says
Table 8.18
• List Types of Bracing Systems that are
“Deemed to Satisfy”
• Gives a value per/m length of Bracing Panel
• Theses values are used to counteract the
Racking Forces calculated.
Before we do this lets see what (f) says
Clause 8.3.6.4 &Table 8.19
Lets Design
Design
Wind Direction 1.2
Racking Force = 11.84
4500
3500
7000
3500
Wind Direction 1.1
Racking Force = 10.5
6000
3000
8000
3000
Wind Direction 2.2
Racking Force = 10.08
Wind Direction 2.1
Racking Force = 12.88
Nominal Wall Bracing
Design – Area 1.1
Wind Direction 1.1
Racking Force = 10.5
Wind Direction 1.1
Bracing Required
10.500
5.250
Still Required
5.250
4500
3500
7000
3500
Nominal
6000
3000
8000
3000
Wind Direction 1.1
Nominal Wall Bracing
Length Value
Total
15.000
0.45
6.750
8.000
0.45
3.600
3.000
0.75
2.250
4.500
0.75
3.375
3.600
0.75
2.700
Total
Max Allowable
18.675
5.25
Design – Area 1.1
Wind Direction 1.1
Racking Force = 10.5
Wind Direction 1.1
Bracing Required
10.500
Nominal
Hoop Iron to External
Corners as (b)
5.250
16.200
Total
21.450
4500
3500
7000
3500
Metal Cross Strapping to Corners
As per Table 8.14 (b)
Wind Direction 1.1
Hoop Iron as per 8.14(b)
Length Value
Total
2.700
1.5
4.050
2.700
1.5
4.050
2.700
1.5
4.050
2.700
1.5
4.050
6000
3000
8000
3000
Note you must do all corners
Regardless of Overkill
Total
16.2
Design – Area 1.1
Wind Direction 1.1
Racking Force = 10.5
Wind Direction 1.1
Bracing Required
10.500
Nominal
Hoop Iron to External
Corners as (b)
5.250
16.200
Total
21.450
4500
3500
7000
3500
Metal Cross Strapping to Corners
As per Table 8.14 (b)
6000
3000
8000
3000
You Still would place
Bracing on Internal Walls
To assist During Constructions
Using any Method (a) is easiest
Wind Direction 1.1
Hoop Iron as per 8.14(b)
Length Value
Total
2.700
1.5
4.050
2.700
1.5
4.050
2.700
1.5
4.050
2.700
1.5
4.050
Total
16.2
Design – Area 1.1
Wind Direction 1.1
Racking Force = 10.5
4500
6000
8000
3000
3000
Wind Direction 1.1
Bracing Required
10.500
Nominal
Hoop Iron to External
Corners as (b)
Hoop Iron to External
Corners as (b)
5.250
16.200
Total
33.600
12.150
3500
7000
3500
Metal Cross Strapping to Corners
As per Table 8.14 (b)
You Still would place
Bracing on Internal Walls
To assist During Constructions
Using any Method (a) is easiest
Wind Direction 1.1
Hoop Iron as per 8.14(b)
Length Value
Total
2.700
1.5
4.050
2.700
1.5
4.050
2.700
1.5
4.050
Total
12.15
Design – Area 1.2
Wind Direction 1.2
Bracing Required
11.840
Nominal
5.920
Still Required
5.920
4500
3500
7000
3500
Wind Direction 1.2
Racking Force = 11.84
6000
3000
8000
3000
Wind Direction 1.2
Nominal Wall Bracing
Length Value
Total
7.000
0.45
3.150
3.500
0.75
2.625
3.500
0.75
2.625
Total
Max Allowable
8.4
5.92
Design – Area 1.2
Wind Direction 1.2
Racking Force = 11.84
Wind Direction 1.2
Bracing Required
11.840
Nominal
Hoop Iron 8.14(b)
14.020
4500
3500
7000
3500
Total
5.920
8.100
6000
3000
8000
3000
Wind Direction 1.2
Hoop Iron as per 8.14(b)
Length Value
Total
2.700
1.5
4.050
2.700
1.5
4.050
Total
Metal Cross Strapping to Corners
As per Table 8.14 (b)
8.100
Design – Area 1.2
Wind Direction 1.2
Racking Force = 11.84
Wind Direction 1.2
11.840
Bracing Required
3500
Nominal
Hoop Iron 8.14(b)
Hoop Iron 8.14(b)
5.920
8.100
8.100
22.120
4500
3500
7000
Total
6000
3000
8000
3000
Bracing to Internal Walls to
1. Spread Bracing thru Structure
2. Assist During Construction
Wind Direction 1.2
Hoop Iron as per 8.14(b)
Length Value
Total
2.700
1.5
4.050
2.700
1.5
4.050
Total
8.100
Design – Area 2.1
Wind Direction 2.1
Bracing Required
12.880
6.440
Still Required
6.440
4500
3500
7000
3500
Nominal
6000
Wind Direction 2.1
Nominal Wall Bracing
Length Value
Total
13.000
0.45
5.850
6.000
0.45
2.700
13.000
0.75
9.750
3000
8000
3000
Wind Direction 2.1
Racking Force = 12.88
Total
Max Allowable
18.3
6.44
Design – Area 2.1
Wind Direction 2.1
Bracing Required
12.880
6.440
16.200
Total
22.640
Wind Direction 2.1
Racking Force = 12.88
4500
3500
7000
3500
Nominal
Hoop Iron as 8.14(b)
6000
3000
8000
3000
Metal Cross Strapping to Corners
As per Table 8.14 (b)
Wind Direction 2.1
Hoop Iron as per 8.14(b)
Length Value
Total
2.700
1.5
4.050
2.700
1.5
4.050
2.700
1.5
4.050
2.700
1.5
4.050
Total
16.2
Design – Area 2.1
4500
6000
8000
3000
3000
Nominal
Hoop Iron as 8.14(b)
Hoop Iron as 8.14(b)
6.440
16.200
8.100
Total
30.740
Wind Direction 2.1
Racking Force = 12.88
3500
7000
3500
Wind Direction 2.1
Bracing Required
12.880
Bracing to Internal Walls to
1. Spread Bracing thru Structure
2. Assist During Construction
Wind Direction 2.1
Hoop Iron as per 8.14(b)
Length Value
Total
2.700
1.5
4.050
2.700
1.5
4.050
Total
8.100
Design – Area 2.2
Nominal
5.040
Still Required
5.040
4500
3500
7000
3500
Wind Direction 2.2
Bracing Required
10.080
6000
3000
8000
3000
Wind Direction 2.2
Racking Force = 10.08
Wind Direction 2.2
Nominal Wall Bracing
Length Value
Total
5.000
0.45
2.250
5.000
0.75
3.750
3.000
0.75
2.250
Total
Max Allowable
8.25
5.04
Design – Area 2.2
Wind Direction 2.2
Bracing Required
10.080
Nominal
Hoop Iron as 8.14(b)
13.140
4500
3500
7000
3500
Total
5.040
8.100
6000
3000
8000
3000
Wind Direction 2.2
Hoop Iron as per 8.14(b)
Length Value
Total
2.700
1.5
4.050
2.700
1.5
4.050
Wind Direction 2.2
Racking Force = 10.08
Total
8.1
Design – Area 2.2
Wind Direction 2.2
Bracing Required
10.080
Nominal
Hoop Iron as 8.14(b)
Hoop Iron as 8.14(b)
17.190
4500
3500
7000
3500
Total
5.040
8.100
4.050
6000
3000
8000
3000
Wind Direction 2.2
Hoop Iron as per 8.14(b)
Length Value
Total
2.700
1.5
4.050
Bracing to Internal Walls to
1. Spread Bracing thru Structure
2. Assist During Construction
Total
4.05
Lets Design
Clause 8.3.6.9
• Top of INTERNAL Bracing Walls must be fixed
to Ceiling or Upper Floor Structure with
equivalent Shear Capacity as to its Bracing
Capacity
See Next Slide for Explanation
Confirmation Learning
• Complete Exercise 42 of your workbook
Connection of Internal Brace Walls
4500
3500
7000
3500
In our Exercise we use Crossed Hoop Iron
6000
3000
8000
3000
Bracing Value = 1.5
Bracing Panel Length = 2.7
Total Force = 1.5 x 2.7
= 4.05kN
Total Force
= 4.05kN
Seasoned Radiata Pine = JD4
1 Fixing at each end of Bracing Panel
= 2 x 2.1kN
= 4.2 (Sufficient)
Wall Frames
• Frames are classified into 2 categories
1. Load Bearing – They are structural frames, they
transfer loads from roof or upper floor to the
supporting floor frame. They can be either
external or internal walls.
2. Non Load Bearing –
- do not support any structural loads.
- They support their own weight
- Non structural loads doors and frame, kitchen
cupboards, driers etc.
- support some live loads eg Doors closing.
Therefore there are some minimum
requirements for these AS 1684.2 cl 6.3.5
AS 1684.2 cl 6.3.5
Wall Components
Trimmers
• Horizontal members fixed between window
studs and door studs.
• Referred to as Sill or Head trimmers
• Usually of the same section size bottom plates
• Openings wider than 1800mm require
trimmers as specified in AS 1684.2 cl6.3.6.6 &
table 6.3
Trimmers
Refer Table 6.3 of your Australian Standard
Trimming Studs
•Run from Trimmers to Plates – Use same Timber Size
•Used to block out Narrow Lintel
•Where use in conjunction with Lintel they may take structural loads
•Must be same depth as wall frame to accept finishes
•May also be referred to as “Jack”, “Soldier”, or “Short” studs
Wall Intersections Blocking
• Placed at intersections of wall frames
• Normally 3 Blocks per intersection
Blocking AS1684.2
What is a Concentrated Load ?
>3000
Stress Grading
• Refers to the Timbers Strength
• Timber must be able to withstand stress loads
placed on them.
• Overloading may cause straining or failure
• 3 types of stress
Compressive
Tensile
Shear
Note Torsional Stress is not discussed
Stress Grading
• Members Sizes will be determined for span
tables
• Generally for Residential Construction sizes will
not be specified by designers
•
•
•
•
Why?
Architect will not want to take responsibility
Engineer will want to charge extra to do this and
Why would a client want to pay for something
that he can get done for nothing
Stress Grading
• Why are members generally specified on
Commercial projects
• AS 1684.2 Residential Timber Framed
Construction Guide
AS 1684.2 Limitations
1.4.4 The Maximum number of storey's of timber shall not exceed 2
1.4.5 The maximum width of a building shall 16 000mm,
Note, if you use AS1684.2 simplified max width = 12 000mm
1.4.6 The maximum wall height shall be 3000mm excluding gable
ends
1.4.7 The maximum roof pitch shall be 35 degrees
Ordering Timber
• Timber is ordered in lineal meters
may be priced in cubic meters
• Increments of 300mm
• Timber should be ordered as required
- avoid unnecessary exposure to weather
- affecting cash flows
- theft
- storage
Material Storage
• Timber should be
stored on gluts
• This allows for airflow
• Care should be taken
in stack sizes
• Stacks can be
strapped for safety
Storage of Materials
• Timber should be stored as close as possible
to work area
Stud Spacing – Other Consideration
Stud Spacing may also be determined by
sheeting
Studs
• Not all external sheeting require critical stud
placement
• Check with LATEST manufactures manual as to
requirements
Harditek (Blue Board)
For Sheet Products Stud Placement is Important
Calculating Stud Lengths
• Finished Floor to Ceiling govern stud length
• Minimum Habitable Room is 2400mm Clear
• Floor Finishes
1. Carpet 20mm
2. Timber Flooring 40mm (Depending on Batten)
• Ceilings
1. 10mm Plasterboard
2. 13mm Plasterboard
Calculating Stud Length
• Double Storey building may have FFL (Finished
Floor Level).
• Allowance must be made for structural
members
• Most Importantly Determine if there are any
height restrictions
• Type of Roof Will affect Stud Heights
Top & Bottom Plates = 90 x 45 F5
Step 1 – Determine Floor & Ceiling
Floor Carpet = 20mm
Ceiling Gyprock = 13mm
Step 2 – Calculate Stud Length
Minimum Clearance = 2400mm
Plus Flooring = 20mm
Plus Ceiling
= 20mm
Wall Height
= 2440mm
less Wall Plates = 90mm
Stud Length
= 2350mm
Ground Fl Finish = Timber (40mm)
First Floor = Carpet (20mm)
Upper Level Joists = 200 x 50 F5
Top & Bottom Plates = 90 x 45
Step 1- Determine SFL (Structural
Floor Level)
SFL First Floor = 28.950 (FFL First Fl)
-20 (Carpet)
SFL= 28.930
SFL Ground Fl = 26.200 (FFL Gnd)
- 40 (Timber)
SFL = 26.160
Step 2 – Calculate Height Difference
Ground Floor
SFL First Floor
= 28.930 –
SFL Ground Fl
= 26.180
Height Difference = 2.750
First Floor
Step 3 – Structural Elements
Height Diff
Less Flooring
Less Floor Joist
Less T & B Plate
= 2.750
= 0.017
= 0.200
= 0.090
Stud Length
= 2.443
Ground Floor
First Floor
Carpet Both Floors (20mm) Ceilings 10mm Plasterboard (Allow 20mm)
Dimensions are clear measurements
Lower level plates
Upper Level Plates
Bottom Plate = 90 x 35 F5
Bottom Plate = 90 x 45 F5
Top Plate
= 90 x 45 F5
Top Plate
= 90 x 70 F5
Calculating Door Heights
•
•
•
•
•
•
•
•
•
On Concrete Slab
Using a standard 2040mm x 820mm
Allow 22mm for Carpet (17mm + 5mm)
2040 mm Door Height
2mm Clearance between Door & Jamb
20mm for Jamb
10mm Clearance between Jamb & Head
15mm Clearance between Jamb & Lintel
Total = 2094mm Say 2100mm
Calculation of Door Width
Calculation of Window
•Check with manufacturer if windows are not on site
•Generally at same height of doors
•Check on elevations for window heights
•15mm Clearance between Jamb & Lintel
•Allow 10mm under sill
Window Width
•Care should be taken when setting out to brick bond!
•Client may want window to line up with internal fitting
•Client may want window dead center of room
Lintels
Construct Wall Frames
•
•
•
•
Number Wall Frames
Clock Wise Direction
Internal Walls Left to Right
Top To Bottom
Setting Out Plates
• Confirm Dimensions of Slab/ Subfloor
Select Suitable Timber & Cut to Length
Tack Together
Mark Appropriate ID Number on Plate
• Mark Required Studs – In Following Order
End Studs
Wall Intersections
Openings
Common Studs
Setting Out Plates
• If required prepare a storey rod with the
appropriate markings (ie Horizontal & Vertical
Bond)
• Set out position of window and doors studs
remembering to allow for required jamb studs
• If required adjust position to match brickbond
• Set out Common Studs, Jack Studs at required
spacing
Preparing Studs
• Use Storey Rod (Pattern Stud) to cut required
studs
• Mark and check out window and door studs
Fixing Wall Frames To Floors
• AS 1684.2
Wall Frame Assembly
What are Advantages & Disadvantages of Prefabricated Wall Frames?
Assembling Wall Frames
Frame Erection
Nominal Fixings For Bottom Plates AS 1684.2
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