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

1. Conventional Roof Framing Class Exercise 2 - 180 Residential Studies Certificate IV 2182D

2. 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.

3. Floor Plan Class Exercise 2 Note: Hyspan LVL Strutting Beams to Dining / Lounge & Bedroom 1 as shown

4. Preliminary Calculations Common Rafter True Length of Common Rafter Pitch 180 Half Span = 8.150 – 0.300 2 = 3.925m Rise = Tan 180 x 3.925 = 1.275m TLCR = 4.127 Rise 1.275 TLCR = 3.925 Cos 180 = 4.127m 180 Half Span 3.925

5. Calculate Common Rafter Span & RLW of Underpurlin 2.064 4.127 2.064 RLW = 4.127 2 = 2.064m Span of Rafter = 2.064m Say 2.100m RLW of Underpurlin = 2.064m Say 2.100m

6. Calculate Eaves Overhang – Eaves RLW 0.788m TL O/Hang = 0.600 + 0.150 COS 180 = 0.788m RLW Eaves = 0.788m 0.150 0.600

7. Calculate Fan Strut Lengths & Distance X. Strut = ? 2.064 2.064 Strut = Tan180 x 2.064 = 0.671 2.064 Strut 0.788 0.671 Dist. X = 1.862 run of rafter = 3.925 100mm width Distance X = Run of rafter divided by 2 less 100mm plate width: 3.925/2 = 1.962 – 100 = 1862

8. Calculate Fan Strut Length 0.671 0.671 Fan Strut =  0.6712 + 0.6712 = 0.949m or = 0.671 cos 450 = 0.949m 0.671 0.949 0.949 Half Spread Fan Strut = 0.671m Fan Strut Length = 0.949m

9. 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

10. Using the information from the Preliminary Calculations & The Job Specification Fill in the Project job sheets to arrive at final design requirements.

11. General Information from Project Details Seasoned S/Wood MGP 15 6 – N3 60Kg/m2 Conventional 2.700 0.600 Fill in comments column with information from project specification

12. Using A.S. 1684.2 (2006) – Section 7 Roof Framing 1. Obtain information for Ceiling Joists to complete job sheet. 2.400 7.2.4 21 2.800 7.3.6 • Page 81 – rule 7.2.4 ceiling joists (building practice) 2. Page 98 – rule 7.3.6 ceiling joists (member sizes) 3. Determine Span Table of supplements (supp. 6, N3, s/softwood, MGP 15) 4. Find allowable spans for 90 x 35 MGP15 ceiling joists from table 21 supp. 6

13. 2. Obtain information for Hanging Beams 7.2.5 2 / 90 x 45 2.475 1.720 2.930 2.050 23 120 x 45 2.730 2.050 120 x 35 2.540 1.225 90 x 45 7.3.7 1.680 1.725 90 x 35 140 x 45 3.770 1.720 2 / 170 x 35 3.770 2.055 170 x 35 3.830 2.055 170 x 35 3.830 2.055 140 x 45 3.300 2.775 N / A • Page 82 – rule 7.2.5 Hanging Beams (building practice) 2. Page 99 – rule 7.3.7 Hanging Beams (member sizes) 3. Determine Span Table of supplements (supp. 6, N3, s/softwood, MGP 15) 4. Determine Hanging Beams to rooms from table 23 supp. 6, MGP15

14. 3. Obtain information for Rafters 7.2.11 0.600 120 x 35 29 2.100 7.3.13 0.788 Fill in comments column with information from project specification & Prelim. Calcs. • Page 86 – rule 7.2.11 Rafters (building practice) 2. Page 105 – rule 7.3.13 Rafters (member sizes) 3. Determine Span Table of supplements (supp. 6, N3, s/softwood, MGP 15) • Determine Rafter Size from table 29 supp. 6, MGP15, N3 • (Check - single or continuous span - roof mass – span – O/hang)

15. 4. Obtain information for Collar Ties 3.805 7.2.16 & 7.3.17 70 x 35 7.6 (page 110) 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. Page 110, Table 7.6 – Collar Ties gives required Information Refer to floor plan to calculate length of collar tie: 7.610 / 2 = 3.805 From Table 7.6 – Ties to 4200mm long for F8/MGP12 or higher stress grade – 70 x 35

16. 5. Obtain information for Ridge board 7.2.12 7.6 (page 110) 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 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

17. Ridge 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. 0.126 Rafter 120 x 35 MGP 15 Seasoned Softwood Length of Plumb Cut Length of Plumb cut = Rafter Depth Cos. Roof Pitch = 0.120 Cos. 180 = 0.126 0.120

18. 5. Obtain information for Ridge board 7.2.12 140 x 19 7.6 (page 110) 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 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

19. 6. Obtain information for Hip Rafter (Hip) Note: Plan shows Roof is a Gable Roof – Therefore NO HIPS REQUIRED

20. 7. Obtain information for Under purlins 7.2.10 7.3.12 3.633m 28 Check section 7 (Roof Framing) for information – rules & tables for Underpurlins Note: Find rules relating to Underpurlins Page 84, Rule 7.2.10 – Underpurlins Page 104, Rule 7.3.12 - Size of Underpurlins Span Table 28 of Supplements 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

21. 8. Obtain information for Struts (Roof Strutting) 90 x 45 70 x 70 0.671m 7.2.15 7.2.15.3 0.949m 7.6 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 From Prelim. Calcs. Fill in lengths for straight & fan struts. Using Table 7.6 Determine section size of Struts – (Tile Roof)

22. 9. Obtain information for Strutting Beams • Use Hyspan LVL Span Tables for Residential Building • Calculate spans for strutting beams from floor plan

23. Beam to Lounge / Dining, Span = 4.110 Beam to Bedroom 1, Span = 3.440

24. 8. Obtain information for Strutting Beams Centre Centre 4.110 3.440 • Use Hyspan LVL Span Tables for Residential Building • Calculate spans for strutting beams from floor plan • Fill in span information • Spacing is centre of rooms • Determine table number from Hyspan LVL tables to select beam section sizes

25. Use table 18 for Beam To Lounge/Dining - Span = 4.110 & Beam to Bedroom 1 - Span = 3.440 Supporting Underpurlins & Hanging Beams Go to Table 18 for member size

26. TILE ROOF AND CEILING Maximum Span (M) RLW = 2.475 B1 = 3.830 L/D Lounge/ Dining Beam Span = 4.110 Lounge/ Dining Beam = 300x75 Bedroom 1 Beam Span = 3.440 Bedroom 1 Beam = 2/200 x 45

27. 8. Obtain information for Strutting Beams Centre Centre 4.110 300 x 75 T 18 2/ 200 x 45 3.440 • Use Hyspan LVL Span Tables for Residential Building • Calculate spans for strutting beams from floor plan • Fill in span information • Spacing is centre of rooms • Determine table numbers from Hyspan LVL tables to select beam section sizes • Fill in Data for Lounge/Dining Beam • Fill in Data for Bedroom 1 Beam

28. 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.

29. Single struts Strutting Beams Under Purlins Fan struts Hanging Beams

30. Class Exercise 2 – Now Complete