Post on 24-Dec-2015
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Estimating Hip Roofs
Estimating Hip Roofs- Rafters
Determine No of Rafters 12 500/ 600 = 20.833 = 21 + 1 = 22 Rafters each side = 44
Pitch = 24⁰
Note – Change of Layout of Ceiling Joists to Accommodate Creepers
Determine Rafter LengthSpan = 6900
Determine Rafter LengthSpan = 6900Half Span = 3450
Determine Rafter LengthSpan = 6900Half Span = 3450Plan Length = 3450
3450
Determine Rafter LengthSpan = 6900Half Span = 3450Plan Length = 3450Pitch = 24°
3450
Determine 1m triangle
24°
1.000
Rise/mRafter Length/m
Plan Length per 1m of Rafter
Hip Length per 1m of Rafter
Determine 1m triangle
• Solve Common Rafter
24°
1.000
1.000 x Tan 24°1.000 ÷ Cos 24°
Plan Length per 1m of Rafter
Hip Length per 1m of Rafter
Determine 1m triangle
• Solve Common Rafter
1.000
0.455
1.094
Determine 1m triangle
• Solve Hip
24°
1.000
0.455
1.094
Plan Length per 1m of Rafter
Hip Length per 1m of Rafter
Determine 1m triangle
• Solve Hip
24°
1.000
0.455
1.094
√2
√(2 + Rise 2)
Determine 1m triangle
• Multipliers
24°
1.000
0.455
1.094
1.414
1.486
This is the multiplier for the Common Rafter
This is the multiplier for the Hip Rafter
Determine 1m triangle
• Multipliers
24°
1.000
0.455
1.094
1.414
1.486
This is the multiplier for the Hip Rafter
Determine Rafter LengthSpan = 6900Plan Length = 3450
Rafter Multiplier = 1.094Hip Multiplier = 1.486
Determine Rafter LengthSpan = 6900Plan Length = 3450Plan length Eaves = 600
Rafter Multiplier = 1.094Hip Multiplier = 1.486
Determine Rafter LengthSpan = 6900Plan Length = 3450Plan length Eaves = 600
Total Plan Length = 4050
Rafter Multiplier = 1.094Hip Multiplier = 1.486
Determine Rafter LengthSpan = 6900Plan Length = 3450Plan length Eaves = 600
Total Plan Length = 4050
Rafter Length = 4050 x 1.094
Rafter Multiplier = 1.094Hip Multiplier = 1.486
Determine Rafter LengthSpan = 6900Plan Length = 3450Plan length Eaves = 600
Total Plan Length = 4050
Rafter Length = 4050 x 1.094 = 4433 + Plumb Cut
Rafter Multiplier = 1.094Hip Multiplier = 1.486
Rafter 90 x 45
100 if < 100 else Rafter Depth
Determine Rafter LengthSpan = 6900Plan Length = 3450Plan length Eaves = 600
Total Plan Length = 4050
Rafter Length = 4050 x 1.094 = 4433 + 100
Rafter Multiplier = 1.094Hip Multiplier = 1.486
Rafter 90 x 45
100 if < 100 else Rafter Depth
Determine Rafter LengthSpan = 6900Plan Length = 3450Plan length Eaves = 600
Total Plan Length = 4050
Rafter Length = 4050 x 1.094 = 4533
Rafter Multiplier = 1.094Hip Multiplier = 1.486
Rafter 90 x 45
Estimating Sheet
No. LengthRafters 90 x 45 Radiata 44 4.533 4.800 211.200 2.30$ 485.76$
Total Linear Rate / lm Cost Order
Item Section Size Material Linear
Estimating Hip Roof - RidgePitch = 24⁰
Overhang 450
Rafter 90 x 45 F7600 c to c
Ridge 140 x 19Purlin 90 x 70 F7
Ridge Runs Between Crown End12.500 -2 x 3450 = 5600 5300 + ½ Rafter Thickness for each hip end5300 + 45 =5645 mm
Estimating Sheet
No. LengthRafters 90 x 45 Radiata 48 4.533 4.800 230.400 2.30$ 529.92$ Ridge 140 x 19 Radiata 1 5.645 5.700 6.000 6.00$ 36.00$
Total Linear Rate / lm Cost Order
Item Section Size Material Linear
Estimating Hip Roof – Hip Rafter
Determine Rafter LengthSpan = 6900Plan Length = 3450Plan length Eaves = 600
Total Plan Length = 4050
Hip Length = 4050 x 1.486
Rafter Multiplier = 1.094Hip Multiplier = 1.486
Rafter 90 x 45Hip 140 x 19
Determine Rafter LengthSpan = 6900Plan Length = 3450Plan length Eaves = 600
Total Plan Length = 4050
Hip Length = 4050 x 1.486 = 6.018 + Hip Depth
Rafter Multiplier = 1.094Hip Multiplier = 1.486
Rafter 90 x 45Hip 140 x 19
Determine Rafter LengthSpan = 6900Plan Length = 3450Plan length Eaves = 600
Total Plan Length = 4050
Hip Length = 4050 x 1.486 = 6018 + 140
Rafter Multiplier = 1.094Hip Multiplier = 1.486
Rafter 90 x 45Hip 140 x 19
Determine Rafter LengthSpan = 6900Plan Length = 3450Plan length Eaves = 600
Total Plan Length = 4050
Hip Length = 4050 x 1.486 = 6158
Rafter Multiplier = 1.094Hip Multiplier = 1.486
Rafter 90 x 45Hip 140 x 19
Estimating Sheet
No. LengthRafters 90 x 45 Radiata 48 4.533 4.800 230.400 2.30$ 529.92$ Ridge 140 x 19 Radiata 1 5.645 5.700 5.700 5.70$ 32.49$
Hip 140 x 19 Radiata 4 6.158 6.300 25.200 5.70$ 143.64$
Total Linear Rate / lm Cost Order
Item Section Size Material Linear
Estimating Hip Roof - PurlinPitch = 24⁰
Overhang 450
Rafter 90 x 45 F7600 c to cTiled Roof
Ridge 140 x 19Purlin 90 x 70 F7Spacing 2200 centres
1 Row Purlins at Centre Span
Deduct ¼ span for every hip
12500 – 2 x 1725 = 9050 allow 150 for joints = 9200 6900 – 2 x 1725 = 3450
Estimating Sheet
No. LengthRafters 90 x 45 Radiata 48 4.533 4.800 230.400 2.30$ 529.92$ Ridge 140 x 19 Radiata 1 5.645 5.700 5.700 5.70$ 32.49$
Hip 140 x 19 Radiata 4 6.158 6.300 25.200 5.70$ 143.64$ Purlin 90 x 75 Radiata 2 9.200 9.300 18.600 3.80$ 70.68$ Purlin 90 x 75 Radiata 2 3.450 3.600 7.200 3.80$ 27.36$
Total Linear Rate / lm Cost Order
Item Section Size Material Linear
Estimating Hip Roof - StrutsPitch = 24⁰
Overhang 600
Rafter 90 x 45 F7600 c to c
Tiled Roof with Flush Gable & Raking Eaves
Ridge 140 x 19
Purlin 90 x 70 F7Span 2700
Struts are Difficult to EstimateDevelop a Best Guest Method
Determine No Required9.050/2700 =3.4= 4= 5 Each Side Determine No Required3.450/2700 =1.28= 2= 3 Each Side
Estimating Gable Roof - StrutsPitch = 24⁰
Overhang 600
Rafter 90 x 45 F7600 c to c
Tiled Roof with Flush Gable & Raking Eaves
Ridge 140 x 19
Purlin 90 x 70 F7Span 2700 Length = Use Rise
Rise = ½ Span x Rise/m= 3450 x 0.455= 1.569
Estimating Sheet
No. LengthRafters 90 x 45 Radiata 48 4.533 4.800 230.400 2.30$ 529.92$ Ridge 140 x 19 Radiata 1 5.645 5.700 5.700 5.70$ 32.49$
Hip 140 x 19 Radiata 4 6.158 6.300 25.200 5.70$ 143.64$ Purlin 90 x 75 Radiata 2 9.200 9.300 18.600 3.80$ 70.68$ Purlin 90 x 75 Radiata 2 3.450 3.600 7.200 3.80$ 27.36$ Struts 90 x 75 Radiata 13 1.569 1.800 23.400 3.80$ 88.92$
Total Linear Rate / lm Cost Order
Item Section Size Material Linear
Estimating Gable Roof – Collar TiesPitch = 24⁰
Overhang 600
Rafter 90 x 45 F7600 c to c
Tiled Roof with Flush Gable & Raking Eaves
Ridge 140 x 19
Purlin 90 x 70 F7Span 2700
Collar Ties 90 x 35
Collar Ties on Every 2nd RafterOn top of PurlinsLength of Ridge / Rafter Spacing / 222/2 = 11+1 @ HALF SPAN12 @ 3450
Estimating Sheet
No. LengthRafters 90 x 45 Radiata 48 4.533 4.800 230.400 2.30$ 529.92$ Ridge 140 x 19 Radiata 1 5.645 5.700 5.700 5.70$ 32.49$
Hip 140 x 19 Radiata 4 6.158 6.300 25.200 5.70$ 143.64$ Purlin 90 x 75 Radiata 2 9.200 9.300 18.600 3.80$ 70.68$ Purlin 90 x 75 Radiata 2 3.450 3.600 7.200 3.80$ 27.36$ Struts 90 x 75 Radiata 13 1.569 1.800 23.400 3.80$ 88.92$
Collar Ties 90 x 45 Radiata 12 3.450 3.600 43.200 2.30$ 99.36$
Total Linear Rate / lm Cost Order
Item Section Size Material Linear
Estimating Tile QuantitiesPitch = 24⁰
Overhang 450
Rafter 90 x 45 F7600 c to c
Tiled Roof with Flush Gable & Raking Eaves
Ridge 140 x 19
Purlin 90 x 70 F7Span 2700
Collar Ties 90 x 35
Tiles 7 per m2
True Length of Rafter = 4433Total Length of Building = 12800 + 2 x 450 = 13.700
Area of Roof = 4433 x 13.7 x 2 = 121.464m2 x 7 tiles per m2
= 850.249 say 851
Estimating Sheet
No. LengthRafters 90 x 45 Radiata 48 4.533 4.800 230.400 2.30$ 529.92$ Ridge 140 x 19 Radiata 1 5.645 5.700 5.700 5.70$ 32.49$
Hip 140 x 19 Radiata 4 6.158 6.300 25.200 5.70$ 143.64$ Purlin 90 x 75 Radiata 2 9.200 9.300 18.600 3.80$ 70.68$ Purlin 90 x 75 Radiata 2 3.450 3.600 7.200 3.80$ 27.36$ Struts 90 x 75 Radiata 13 1.569 1.800 23.400 3.80$ 88.92$
Collar Ties 90 x 45 Radiata 12 3.450 3.600 43.200 2.30$ 99.36$ Roof Tiles 851.000 3.00$ 2,553.00$
Total 3,545.37$
Total Linear Rate / lm Cost Order
Item Section Size Material Linear