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

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