Conventional Roof Framing Class Exercise 2 - 18 0 Residential Studies Certificate IV 2182D

Conventional Roof Framing

Class Exercise 2 - 180

Residential Studies Certificate IV2182D

Using the Floor Plan & Details provided

complete the Preliminary Calculations

so that the most economical Size, Span and Spacing

Of the Ceiling and Roof members can be achieved.

Note: Hyspan LVL Strutting Beams to Dining / Lounge & Bedroom 1 as shown

2.7700.470 1.070 0.970 1.190 0.8500.8300.970 1.790 1.930 1.8101.310 0.4700.970 1.190 0.970 3.350

0.100 1.680

0.100

4.580 0.100

0.270 3.300 2.620 0.1001.0000.100 2.540 3.770

0.1000.750

2.1100.1001.400

0.1000.600

0.1004.250 0.250

0.350

0.530

0.1201.5502.7700.4703.6100.9501.6901.4301.6900.9502.530 0.950

22.910

2.3300.995

0.270 3.3050.100

2.730

0.100

0.500

0.100

2.930

0.100

3.770

0.100

7.660 0.250

1.00021.910

1.90

00.

100

1.690

0.10

0

0.25

0

2.4

500.

990

4.1

100.

250

1.80

0

3.4

40

0.25

0

3.94

04

.210

0.600

0.25

0

2.4

500.

1000.90

0 0.10

0

2.00

0

0.10

0

2.00

00.

250

1.80

01.

650

4.1

00

0.27

00.

270

7.6

10

8.15

0

.600

Direction of Ceiling Joists

Workshop

Bed3 Bed 2Family

Dining

Lounge

Bed 1

Entry

KitchenE.S.BathW.C.L'dry

Garage Hall

D1

D2

D3

D4

D5

D6

D7

D8

D9

D10

D11

D12D13

D14

D15

W1 W2 W3 W4 W6 W7

W8

W9W10W11W12W13W14

Floor Plan John Bridges

August 2004Floor Plan Class Exercise 2

Preliminary Calculations

Common Rafter

True Length of Common Rafter Pitch 180

180

Half Span 3.925

Rise 1.275

Half Span = 8.150 – 0.300 2= 3.925m

Rise = Tan 180 x 3.925 = 1.275m

TLCR = 4.127

TLCR = 3.925 Cos 180

= 4.127m

Calculate Common Rafter Span & RLW of Underpurlin

4.127

RLW = 4.127 2

= 2.064m

2.064

2.064

RLW of Underpurlin = 2.064m Say 2.100m

Span of Rafter = 2.064m Say 2.100m

Calculate Eaves Overhang – Eaves RLW

0.150 0.600

TL O/Hang = 0.600 + 0.150 COS 180

= 0.788m

0.788m

RLW Eaves = 0.788m

Calculate Fan Strut Lengths & Distance X.

2.064

2.064

0.788

Strut = ?

2.064

Strut = Tan180 x 2.064 = 0.671

0.671

run of rafter = 3.925

Strut

Dist. X = 1.862

Distance X = Run of rafter divided by 2 less 100mm plate width: 3.925/2 = 1.962 – 100 = 1862

100mm

width

Calculate Fan Strut Length

0.671

0.671 0.671

Fan Strut = 0.6712 + 0.6712

= 0.949m

or

= 0.671 cos 450

= 0.949m

0.949 0.949

Half Spread Fan Strut = 0.671m

Fan Strut Length = 0.949m

Summary:

Rafter Span = 2.064 Say 2.100

RLW Underpurlin = 2.064 Say 2.100

Overhang eaves = 0.788

Purlin horizontal Set Out, “Distance X” = 1.862

Half Spread Fan Strut = .671

Full spread Fan Strut = 1.342

Fan Strut Length = 0.949

Using the information from the Preliminary Calculations&

The Job Specification

Fill in the Project job sheets to arrive at final design requirements.

Member Rule/Table Size CommentsTimber Species

Timber Grade

Supp. No.

Roof Mass

Type/Construct.

Floor to Ceiling height

Eaves Width

Seasoned S/Wood

Fill in comments column with information from project specification

MGP 15

6 – N3

60Kg/m2

Conventional

2.700

0.600

General Information from Project Details

Using A.S. 1684.2 (2006) – Section 7 Roof Framing

1. Obtain information for Ceiling Joists to complete job sheet.

Member Rule/Table Size Comments

Ceiling Joists R

T

R

90 x 35

@600mmc/c

Single Span

Continuous Span (over more than 1 span)

1. Page 81 – rule 7.2.4 ceiling joists (building practice)

7.2.4

2. Page 98 – rule 7.3.6 ceiling joists (member sizes)

7.3.6

3. Determine Span Table of supplements (supp. 6, N3, s/softwood, MGP 15)

21

4. Find allowable spans for 90 x 35 MGP15 ceiling joists from table 21 supp. 6

2.400

2.800

2. Obtain information for Hanging Beams


Room Span CLW

Hanging Beams R

T

R

Bedroom 1

Bedroom 2

Bedroom 3

Bath / WC

Laundry

Kitchen

Family

Dining

Lounge

Garage

W/shop

1. Page 82 – rule 7.2.5 Hanging Beams (building practice)

7.2.5

2. Page 99 – rule 7.3.7 Hanging Beams (member sizes)

7.3.7


23

4. Determine Hanging Beams to rooms from table 23 supp. 6, MGP15

2.475 1.7202.930 2.050

2.730 2.0502.540 1.225 1.680 1.725

3.770 1.720

3.770 2.055

3.830 2.055

3.830 2.055

3.300 2.775

2 / 90 x 45

120 x 45120 x 35

140 x 45

2 / 170 x 35

170 x 35

170 x 35

N / A

90 x 35

140 x 45

90 x 45

3. Obtain information for Rafters


Common Rafter R

T

R

Rafter Spacing

Span

Eaves O/Hang

Underpurlin is mid-span of Rafter

Fill in comments column with information from project specification & Prelim. Calcs.

0.600

2.100

0.788

1. Page 86 – rule 7.2.11 Rafters(building practice)

7.2.11

2. Page 105 – rule 7.3.13 Rafters (member sizes)

7.3.13


29

4. Determine Rafter Size from table 29 supp. 6, MGP15, N3(Check - single or continuous span - roof mass – span – O/hang)

120 x 35

4. Obtain information for Collar Ties


Collar Ties R

T

or

Length

Check section 7 (Roof Framing) for information – rules & tables for Collar Ties

Note: Find rules relating to Collar Ties.

Page 90 Rule 7.2.16 & Page 109, Rule 7.3.17 – Other members or Components, states that Table 7.6 give details for miscellaneous roof framing members not given in span tables of the supplements.

7.2.16 &7.3.17

Page 110, Table 7.6 – Collar Ties gives required Information

7.6 (page 110)

Refer to floor plan to calculate length of collar tie: 7.610 / 2 = 3.805

3.805

From Table 7.6 – Ties to 4200mm long for F8/MGP12 or higher stress grade – 70 x 35

70 x 35

5. Obtain information for Ridge board


Ridge R

T

Not Strutted

Check section 7 (Roof Framing) for information – rules & tables for Ridge boards

Note: Find rules relating to Ridge boards

Page 86, Rule 7.2.12 – The size of Ridge boards shall be determined from Table 7.6

7.2.12

7.6 (page 110)

Table 7.6 Ridge boards – Refers to Unstrutted ridges in coupled roofs has having a depth not less than length of Rafter Plumb-Cut x 19mm thick

Rafter 120 x 35 MGP 15 Seasoned Softwood

Ridge

0.120

Length of Plumb Cut

Length of Plumb cut = Rafter Depth Cos. Roof Pitch

= 0.120 Cos. 180

= 0.126

0.12

6

Refer Table 7.6 (AS 1684.2) page 110, Ridge depth = rafter plumb cut x 19mm thick.

Therefore use 140 x 19 MGP 15 S/wood.

5. Obtain information for Ridge board


Ridge R

T

Not Strutted

Check section 7 (Roof Framing) for information – rules & tables for Ridge boards

Note: Find rules relating to Ridge boards

Page 86, Rule 7.2.12 – The size of Ridge boards shall be determined from Table 7.6

7.2.12

7.6 (page 110)

Table 7.6 Ridge boards – Refers to Unstrutted ridges in coupled roofs has having a depth not less than length of Rafter Plumb-Cut x 19mm thick

Calculate Rafter Plumb-Cut Length - 0.120 = 0.126 (Therefore 140 x 19 Ridge)cos 180

140 x 19

6. Obtain information for Hip Rafter (Hip)


Hip Rafter R

R

T

Note:Plan shows R

oof is a G

able Roof –

Therefore NO H

IPS REQUIR

ED

7. Obtain information for Under purlins


Underpurlin R

R

T

140 x 70

Span Direct from Span Tables of Supplements.

Max. Span Interpolated =

Check section 7 (Roof Framing) for information – rules & tables for Underpurlins

Note: Find rules relating to Underpurlins

Page 84, Rule 7.2.10 – UnderpurlinsPage 104, Rule 7.3.12 - Size of Underpurlins Span Table 28 of Supplements

7.2.10

7.3.12

28

Refer Table 28 – Continuous Span - for allowable span to Underpurlin (Rafter spacing = 0.600, RLW = 2100 & Roof Mass = 60Kg/m2)

Interpolate allowable Max. Span for Underpurlin size 140 x 70 from Table 28

3.633m

8. Obtain information for Struts (Roof Strutting)


Struts R

R

T

or

Straight Strut Length =

Fan Strut Length =

Check section 7 (Roof Framing) for information – rules & tables for Struts

Note: Find rules relating to Struts

Page 87, Rule 7.2.15 – Roof Strutting & Page 90, Rule 7.2.15.3 Fan Struts.Page 109, Rule 7.3.17 - The size of Miscellaneous roof members

shall be determined from Table 7.6

7.2.15

7.2.15.3

7.6

From Prelim. Calcs. Fill in lengths for straight & fan struts.

0.671m

0.949m

Using Table 7.6 Determine section size of Struts – (Tile Roof)

90 x 45

70 x 70

9. Obtain information for Strutting Beams


Strutting Beams

•Supporting roof

&

Ceiling Loads.

•Use: Hyspan LVL Location Span Spacing

Lounge/Dining

Bedroom 1

• Use Hyspan LVL Span Tables for Residential Building

• Calculate spans for strutting beams from floor plan

2.7700.470 1.070 0.970 1.190 0.8500.8300.970 1.790 1.930 1.8101.310 0.4700.970 1.190 0.970 3.350

0.100 1.680

0.100

4.580 0.100

0.270 3.300 2.620 0.1001.0000.100 2.540 3.770

0.1000.750

2.1100.1001.400

0.1000.600

0.1004.250 0.250

0.350

0.530

0.1201.5502.7700.4703.6100.9501.6901.4301.6900.9502.530 0.950

22.910

2.3300.995

0.270 3.3050.100

2.730

0.100

0.500

0.100

2.930

0.100

3.770

0.100

7.660 0.250

1.00021.910

1.90

00.

100

1.690

0.10

0

0.25

0

2.4

500.

990

4.1

100.

250

1.80

0

3.4

40

0.25

0

3.94

04

.210

0.600

0.25

0

2.4

500.

1000.90

0 0.10

0

2.00

0

0.10

0

2.00

00.

250

1.80

01.

650

4.1

00

0.27

00.

270

7.6

10

8.15

0

.600


Workshop

Bed3 Bed 2Family

Dining

Lounge

Bed 1

Entry


Garage Hall

D1

D2

D3

D4

D5

D6

D7

D8

D9

D10

D11

D12D13

D14

D15

W1 W2 W3 W4 W6 W7

W8

W9W10W11W12W13W14


August 2004Beam to Lounge / Dining, Span = 4.110 Beam to Bedroom 1, Span = 3.440



Strutting Beams

•Supporting roof

&

Ceiling Loads.


Lounge/Dining

Bedroom 1



• Fill in span information

4.110

3.440

• Spacing is centre of rooms

Centre

Centre

• Determine table number from Hyspan LVL tables to select beam section sizes

Use table 18 for BeamTo Lounge/Dining -Span = 4.110

&Beam to Bedroom 1 -Span = 3.440

Supporting Underpurlins& Hanging Beams

Go to Table 18for member size

RLW = 2.475 B1 = 3.830 L/D

Lounge/ Dining Beam Span = 4.110

Bedroom 1 Beam Span = 3.440

TILE ROOF AND CEILINGMaximum Span (M)

Lounge/ Dining Beam = 300x75

Bedroom 1 Beam = 2/200 x 45



Strutting Beams

•Supporting roof

&

Ceiling Loads.


Lounge/Dining

Bedroom1



• Fill in span information

4.110

3.440

• Spacing is centre of rooms

Centre

Centre

• Determine table numbers from Hyspan LVL tables to select beam section sizes

• Fill in Data for Lounge/Dining Beam

300 x 75

• Fill in Data for Bedroom 1 Beam

T 182/ 200 x 45

Part A can now be completed.

On the plan supplied clearly mark all Hanging Beams, Underpurlins

and any Strutting Beams & / or Special Strutting Beams supporting

Roof and Ceiling loads.

2.7700.470 1.070 0.970 1.190 0.8500.8300.970 1.790 1.930 1.8101.310 0.4700.970 1.190 0.970 3.350

0.100 1.680

0.100

4.580 0.100

0.270 3.300 2.620 0.1001.0000.100 2.540 3.770

0.1000.750

2.1100.1001.400

0.1000.600

0.1004.250 0.250

0.350

0.530

0.1201.5502.7700.4703.6100.9501.6901.4301.6900.9502.530 0.950

22.910

2.3300.995

0.270 3.3050.100

2.730

0.100

0.500

0.100

2.930

0.100

3.770

0.100

7.660 0.250

1.00021.910

1.90

00.

100

1.690

0.10

0

0.25

0

2.4

500.

990

4.1

100.

250

1.80

0

3.4

40

0.25

0

3.94

04

.210

0.600

0.25

0

2.4

500.

1000.90

0 0.10

0

2.00

0

0.10

0

2.00

00.

250

1.80

01.

650

4.1

00

0.27

00.

270

7.6

10

8.15

0

.600


Workshop

Bed3 Bed 2Family

Dining

Lounge

Bed 1

Entry


Garage Hall

D1

D2

D3

D4

D5

D6

D7

D8

D9

D10

D11

D12D13

D14

D15

W1 W2 W3 W4 W6 W7

W8

W9W10W11W12W13W14


August 2004Strutting Beams

Hanging Beams

Under PurlinsSingle struts

Fan struts

Class Exercise 2 – Now Complete

Documents

Conventional Roof Framing Class Exercise 2 - 18 0 Residential Studies Certificate IV 2182D