bcgca3005b construct ceiling frames. intoduction
TRANSCRIPT
BCGCA3005BConstruct Ceiling Frames
Intoduction
•Ceiling Frame is the structure between the top of walls and the roof
•Enclose the Room
•Frame Consists of Ceiling Joists, Ceiling Trimmers, Hangers, Hanging Beams
•Used in Skillion, Gable, Hip Roof
Ceiling Joists
•Horizontal Members with ends rested on top wall plate
•Generally spaced at 450mm or 600mm
•Initially ceiling material will determine spacing
•Sizes and Grading are determined from Span Tables
Ceiling Lining may be nailed directly to Joists
Provide Lateral Tie between opposing Rafters
Ceiling Joists
Typical Residential Design(Coupled Roof)
Portal Frame DesignWalls Require Alternate Bracing
Butressing
Definition – Coupled Roof
Non Coupled Roof
Installation of Ceiling Joists
Tops of Ceiling Joist may be trimmed so as not to protrude
AS 1684.2 Ceiling Joists
•Ceiling Joists shall be spaced to support ceiling linings
•For Coupled Roofs•Ceiling Joists run in same direction as rafters•Be in single lengths or spliced•Same spacing as Rafters
Ceilings Provide Diaphragm Bracing
Ceiling are an Important Structure
• Support For Ceiling Linings• Tie bases of Rafters (Stop Spreading)• Straighten Walls (Between Intersecting Walls)• Diaphragm Bracing (9000mm Max)
Joining Ceiling Joists• Be only made at points of support• Lapped over support 3 times depth
- 6 hand driven nails 75mm x 3.8- 8 machine driven nails 75mm x 3.08- or 1 M12 Bolt
• Butt joined - fish plates to each side- minimum length - 6 x depth of joist- 19mm x Depth of Ceiling Joist
• Nailing plates as per manufacturers detail
Excercise
• Complete Question 6
Selecting Members
Single SpanCeiling Joist A x = 2000mmF5 @ 450 c to c
What size Ceiling Joist is Required ?
10mm Plasterboard Direct Fix
Remember First Check the NOTES!
What are Ceiling Masses ? Refer Appendix B – AS 1684.2
From Appendix B10mm Plaster Board = 7.5kg/sqmTherefore OK
450 CentresNext Highest Span above Required 2000mm Span
Check Grade !
Refer p99 AS1684.2
Selecting Members
Single SpanCeiling Joist A x = 2000mmF5 @ 450 c to c120mm x 35mm
Single SpanCeiling Joist B x = 2700mmF7 @ 450 c to c.
What Size CeilingJoists are required?
Check for Required Grade !450 c to cNext Largest span after 2700mm
Selecting Members
Single SpanCeiling Joist B x = 2500mmF7 @ 450 c to c120mm x 45mm
Ceiling Joist A & B – AS 1684 requires joists to be Continuousx + y = 4500mmF5 @ 450 c to cNote – Maximum Span is 2700mm, 4700mm is irrelevant
Continuous Spans
10mm Plasterboard Direct Fix
Next Largest span after 2700mm 450 c to c Continuous Span
Check For Required Grade !
Compare Single to Continuous
Ceiling Joist A & B as Continuous Joist450 c to c,10mm Plasterboard120 x 35 F5 is Sufficient
120 x 45 F7120 x 35 F5
10mm Plasterboard Direct Fix
Exercise
• Complete Question 5 on WorkbookUsing MGP 10 select suitable Ceiling Joints
Joist X =
Joist Y =
Using MGP 10 select suitable Ceiling Joints for continuous span
Max Span Required
Ceiling Joist size =
120 x 35
140 x 35
3500
120 x 35
Why Continuous Spans
Continuous Span
Framing Openings in Ceilings
• AS 1684.2 cl 7.2.4.4• Openings up to 1000mm – same size as ceiling• 1000mm up to 3000mm – width increased
(accumulatively) by 20% for every 300mm of opening or part there of.
Ceiling Openings Example
Ceiling Joists 90 x 45 MGP 10 Radiata Pine
1800 Square Opening
1800 – 1000 = 800 (1000mm being maximum allowable to use same members)
800mm divided by 300mm = 2.667 therefore 3 increments
45mm x 1.2 = 54mm 1st Increase by 20%54mm x 1.2 = 65mm 2nd Increase by 20%65mm x 1.2 = 78mm 3rd Increase by 20%
Therefore minimum size is 90mm x 78mm
Excercise
• Complete Questions 4 & 5 in the Worksheet
What items determine the sizing of Ceiling Joists?
Refer to Span Tables
Complete Questions 7 & 7.1 of Workbook
Hanging Beams- also referred to as Hangers
Hanging Beams provide support to Ceiling Joists where walls are available
Connecting Hanging Beams to Ceiling Joists
Ceiling Dog
Connecting Hanging Beams to Ceiling Joists
Unitie
4 Timber Connector Nails in Each Member
Connecting Hanging Beams to Ceiling Joists
Triple Grips
4 @ 35mm x 3.15 Connector Nails in to each member
End Support of Hanging Beams
Hanging Beams shall be nailed or bolted to a rafter
Where more than 2/3 of the Beam needs to be trimmed a ceiling trimmer is required
Beam Shall Bear Full Width of Plate on Packing
Isometric View
Complete Exercise 8 of the Work Book
Restraining Deep Hanging BeamsWhat is a Deep Beam ? Where depth is Greater
than 7 times the Width
Hanging Beams
Packing Full Width of Plate. Build up to top of Ceiling Joists
Where Beam is longer than 3000mm stud required directly below
Where this occurs at Gable Ends , no ceiling joists to brace end wallThe Beam will also act as a “Binder”
Gable Ends
Binders refer AS 1684.2 cl 6.2.5.1
At Gable Ends walls do not have Ceiling Joists to Brace them
Work Book
Complete Question 9
Selecting Member SizesHanging Beam
Refer Question 10
Ceiling Joist Span = 3600mmHanging Span = 4500mm
Check Notes What is Ceiling Load Width ?
Hanging Beam is similar to having a wall in same location
Without Hanging Beam all Load is transferred to walls
What is Ceiling Load Width ? 1800mm
What is the Hanging Beam Span ? 4500mm
Required Beam190 x 45 MGP 10
Complete Workbook Q10
Counter Beamscalled Hanging Beams in the TAFE GUIDE
Reduce Span of Hanging BeamAt 90º to Hanging Beams
Supported on WallsWith stud directly below if longer than 3000mm
Trimmed for Roof FinishesSimilar to Hanging Beams
Intersection of Hanging & Counter
Note – Counter Beam is Supporting Hanging Beam
Intersection of Hanging & Counter
Intersection of Hanging & Counter
Hanging Beam
Counter Beam
Packer to ProvideClearance to Ceiling
Complete Q11 & 11.1 in Workbook
Counter Beams
Reduces Span of Hanging Beam
x/2
x/2
Without Counter Beam, Hanging Span is x
Once Counter Beam is installed, Hanging Beam Span is now x/2
Load Flow
Load Flow
Selecting Member
Counter Beam Span = 3600mmHanging Beam Length (x) = 6000mm
Check Notes
X= 8000mmBeam Span 4000mm
Check Grade
Counter Beam Spacing = x/2There may be more than 1
Determine Suitable Counter Beam
Complete Questions 11 & 12
F8
MGP 12
F14
F27
190 x 45
170 x 35
175 x 40
140 x 45 or 2/120 x 35
Counter beam span 3600Hanging Beam Length (x) 6000
Combined Strutting/Hanging Beams
Reduce Span of Ceiling Joists and Purlin
Supported on WallsWith stud directly below if longer than 3000mm
Roof Load Strutted down to Hanging Beam
Check Grade
Check Notes
Roof Masses
First we need to determine what ceiling load it carrying?
Ceiling Load Width (CLW)
Ceiling Joist Span (x) = 4200
Hanging Beam Span = 6000
Rafter Span (B) = 4500
Therefore CLW = 2100
Sheet Roof
Remember what we are trying Work out is what load is the member carrying
Next we need to calculate what roof load it is carrying?
Roof Area SupportSheet Roof
Why A ?
Strut Down to Beam from Purlin(Roof)
Struts down to top plate distance between these 2 struts is A
Therefore strut takes load ½ way between other supports 5000/2 = AA = 2500
Ceiling Joist Span (x) = 4200
Hanging Beam Span (A) = 5000
Rafter Span (B) = 4500
Roof Area SupportWhy B?
Rafter is supported by Purlin
Ceiling Joist Span (x) = 4200
Hanging Beam Span (A) = 5000
Rafter Span (B) = 4500
Rafter Load is Transferred thruPurlin StrutRidge Strut,Top Plate
Therefore Beam takes load ½ way between supports (4500/2) = 2250
Next we need to calculate what roof load it is carrying?
2.250 (Rafter Span) x 2.500 ( HB Span)
=5.625
Remember Ceiling Load Width = 2100
Required Hanging Beam Span = 5000
Required Hanging Beam Span = 5000mm
Combined Strutting/Counter Beams
Reduce Span of Hanging Beam
Supported on WallsWith stud directly below if longer than 3000mm
Roof Load Strutted down to Hanging Beam
Strutting Beam
No Ceiling Support
Load Flow
Complete Q13
Alternate Ceilings P288
Flat Roof Construction
Exposed Grid CeilingsPage 289
Exposed Grid Ceiling
Concealed Fixed Suspended CeilingPage 290
Direct Fix SystemsPage 290
Estimating
Determine No of Ceiling Joists
= Length – 2 x Plate Width – 1 x Ceiling Joist Thickness
Estimating
Determine No of Ceiling Joists (CJ 90 x 45)
= 12500– 180 – 45= 12275
Estimating
Determine No of Ceiling Joists 12275 ÷ 600 = 20.458= 21 + 1= 22 @6900
Estimating
Determine Even Spacing 12275 ÷ 21 = 584.524
EstimatingDetermine Joist Layout
Joist No1 02 5853 11694 17545 23386 29237 35078 40929 4676
10 526111 584512 643013 701414 759915 818316 876817 935218 993719 1052120 1110621 1169022 12275
EstimatingJoist No
1 02 5853 11694 17545 23386 29237 35078 40929 4676
10 526111 584512 643013 701414 759915 818316 876817 935218 993719 1052120 1110621 1169022 12275Determine No of Ceiling Joists
By Bay
Bay 1
Bay 1 = Joist 1 to Joist 9 = 9
EstimatingJoist No
1 02 5853 11694 17545 23386 29237 35078 40929 4676
10 526111 584512 643013 701414 759915 818316 876817 935218 993719 1052120 1110621 1169022 12275Determine No of Ceiling Joists
By Bay
Bay 1
Bay 1 = Joist 1 to Joist 9 = 9Bay 2 = Joist 10 to 17 = 7
Bay 2
EstimatingJoist No
1 02 5853 11694 17545 23386 29237 35078 40929 4676
10 526111 584512 643013 701414 759915 818316 876817 935218 993719 1052120 1110621 1169022 12275Determine No of Ceiling Joists
By Bay
Bay 1
Bay 1 = Joist 1 to Joist 9 = 9Bay 2 = Joist 10 to 17 = 7 Bay 3 = Joist 18 to 22 = 5
Bay 2 Bay 3
Place Hanging & Counter Beams
Single Span greater than 2000mm
No. LengthBay 1 90 x 45 MGP 10 18 3.600 3.600 64.800 -$ Bay 2
1 90 x 45 MGP 10 9 3.600 3.600 32.400 -$ 2 90 x 45 MGP 10 9 3.900 3.900 35.100 -$
Bay 31 90 x 45 MGP 10 7 6.000 6.000 42.000 -$ 2 90 x 45 MGP 10 7 1.500 1.500 10.500 -$
Trimmers 90.45 MGP 10 19 0.600 0.600 11.400 -$
Total Linear Rate / lm Cost Order
Item Section Size Material Linear
Ceiling Trimmers
6650 ÷ 600 = 11.083 = 12+ 1 to Close = 13+ 1 for intersection =14
Ceiling Trimmers
6650 ÷ 600 = 11.083 = 12+ 1 to Close = 13+ 1 for intersection =14
3350 ÷ 600 = 5.6 = 6+ 1 to Close = 7
Ceiling Trimmers
6650 ÷ 600 = 11.083 = 12+ 1 to Close = 13+ 1 for intersection =14
800 ÷ 600 = 1.3 = 2+ 1 to Close = 3
3350 ÷ 600 = 5.6 = 6+ 1 to Close = 7
Ceiling Trimmers
6650 ÷ 600 = 11.083 = 12+ 1 to Close = 13+ 1 for intersection =14
800 ÷ 600 = 1.3 = 2+ 1 to Close = 3
3350 ÷ 600 = 5.6 = 6+ 1 to Close = 7
Answer23 @ 0.600 = 13.800
Note as blocks no need to specify length
No. LengthBay 1 90 x 45 MGP 10 18 3.600 3.600 64.800 -$ Bay 2
1 90 x 45 MGP 10 9 3.600 3.600 32.400 -$ 2 90 x 45 MGP 10 9 3.900 3.900 35.100 -$
Bay 31 90 x 45 MGP 10 7 6.000 6.000 42.000 -$ 2 90 x 45 MGP 10 7 1.500 1.500 10.500 -$
Trimmers 90.45 MGP 10 23 0.600 0.600 13.800 -$
Total Linear Rate / lm Cost Order
Item Section Size Material Linear
Determine Hanging Beams
3 @ 5450
1 @ 4400
2 @ 2850
1 @ 3300
1 @ 3850
No. LengthBay 1 90 x 45 MGP 10 18 3.600 3.600 64.800 -$ Bay 2
1 90 x 45 MGP 10 9 3.600 3.600 32.400 -$ 2 90 x 45 MGP 10 9 3.900 3.900 35.100 -$
Bay 31 90 x 45 MGP 10 7 6.000 6.000 42.000 -$ 2 90 x 45 MGP 10 7 1.500 1.500 10.500 -$
Trimmers 90.45 MGP 10 23 0.600 0.600 13.800 -$
A1 240 x 45 F27 3 5.450 5.700 17.100 -$ A2 240 x 45 F27 1 4.400 4.500 4.500 -$ A3 190 x 35 F11 1 2.850 3.000 3.000 -$
A 4.1 240 x 45 F27 1 3.300 3.300 3.300 -$ A 4.2 240 x 45 F27 1 3850.000 3.900 3.900 -$
Total Linear Rate / lm Cost Order
Item Section Size Material Linear
Counter Beam
1 @ 3.400
No. LengthBay 1 90 x 45 MGP 10 18 3.600 3.600 64.800 -$ Bay 2
1 90 x 45 MGP 10 9 3.600 3.600 32.400 -$ 2 90 x 45 MGP 10 9 3.900 3.900 35.100 -$
Bay 31 90 x 45 MGP 10 7 6.000 6.000 42.000 -$ 2 90 x 45 MGP 10 7 1.500 1.500 10.500 -$
Trimmers 90.45 MGP 10 23 0.600 0.600 13.800 -$
A1 240 x 45 F27 3 5.450 5.700 17.100 -$ A2 240 x 45 F27 1 4.400 4.500 4.500 -$ A3 190 x 35 F11 1 2.850 3.000 3.000 -$
A 4.1 240 x 45 F27 1 3.300 3.300 3.300 -$ A 4.2 240 x 45 F27 1 3850.000 3.900 3.900 -$
C. Beam 170 x 45 F27 1 3.400 3.600 3.600 -$
Total Linear Rate / lm Cost Order
Item Section Size Material Linear
Ceiling Dogs
One at every Hanging Beam
Two at Ceiling Joist Joints
Every Time a joist crosses a beam
No. LengthBay 1 90 x 45 MGP 10 18 3.600 3.600 64.800 -$ Bay 2
1 90 x 45 MGP 10 9 3.600 3.600 32.400 -$ 2 90 x 45 MGP 10 9 3.900 3.900 35.100 -$
Bay 31 90 x 45 MGP 10 7 6.000 6.000 42.000 -$ 2 90 x 45 MGP 10 7 1.500 1.500 10.500 -$
Trimmers 90.45 MGP 10 23 0.600 0.600 13.800 -$
A1 240 x 45 F27 3 5.450 5.700 17.100 -$ A2 240 x 45 F27 1 4.400 4.500 4.500 -$ A3 190 x 35 F11 1 2.850 3.000 3.000 -$
A 4.1 240 x 45 F27 1 3.300 3.300 3.300 -$ A 4.2 240 x 45 F27 1 3850.000 3.900 3.900 -$
C. Beam 170 x 45 F27 1 3.400 3.600 3.600 -$
C Dogs 120
Total Linear Rate / lm Cost Order
Item Section Size Material Linear
Planning