Broken Hip Roof

Lay out of Hip & Valley Roof Roof Pitch = 25⁰

Lay out of Hip & Valley Roof Roof Pitch = 25⁰ What Members define Creeper side cut

Lay out of Hip & Valley Roof Roof Pitch = 25⁰ What Members define Valley Creeper side cut What Members define Creeper side cut Half Span Common Rafter

Lay out of Hip & Valley Roof Roof Pitch = 25⁰ What Members define Valley Creeper side cut Half Span Common Rafter What Members define Creeper side cut Half Span Common Rafter

Lay out of Hip & V Roof Roof Pitch = 25⁰ What Members define Creeper side cut Half Span Common Rafter

Lay out of Broken Hip Roof Roof Pitch = 25⁰ No new bevels need to be developed

Lay out of Broken Hip Roof Roof Pitch = 25⁰ All Bevels and edge cuts are the same as a hip roof Broken Hip As Span is not the same the rise will not be the same

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Hip Rafter Minor Span Crown End Minor Span Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Common Rafter Major Span Common Rafter Minor Span Hip Rafter Major Span Valley Rafter Minor Span Centring Rafter Minor Span Crown End Major Span Crippled Centring Rafter Broken Hip Centring Rafter Major Span Gathering Point

Lay out of Broken Hip Roof Roof Pitch = 25⁰ With the more complex roof a roof is. It is important to plan & determine as much of the roof offsite that you can Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Lay out of Broken Hip Roof Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Rafter Spacing 300mm 1.489 1.103 0.466 Determine Required Lengths Common Rafter Major Span = 1.000 √2

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Lay out of Broken Hip Roof Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Rafter Spacing 300mm 1.489 1.103 0.466 Determine Required Lengths Common Rafter Major Span = Plan Length x Rafter Length / m = (1000 – 17.5) x 1.103 = 982.5 x 1.103 = 1084 1.000 √2

Common Rafter – Major Span Plumb Cut 1.489 1.103 0.466 1.000 √2 Plumb Cut

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Lay out of Broken Hip Roof Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Rafter Spacing 300mm 1.489 1.103 0.466 Determine Required Lengths Common Rafter Major Span = 1084 Common Rafter Minor Span = 1.000 √2

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Lay out of Broken Hip Roof Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Rafter Spacing 300mm 1.489 1.103 0.466 Determine Required Lengths Common Rafter Major Span = 1084 Common Rafter Minor Span = Plan Length x Rafter Length / m = (675 – 17.5) x 1.103 = 657.5 x 1.103 = 725 1.000 √2

Common Rafter – Minor Span Plumb Cut 1.489 1.103 0.466 1.000 √2 Plumb Cut As Major & Minor Span are the same pitch the plumb cuts must be the same

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Lay out of Broken Hip Roof Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Rafter Spacing 300mm 1.489 1.103 0.466 Determine Required Lengths Common Rafter Major Span = 1084 Common Rafter Minor Span = 725 Rise Main Roof = (½ Span – ½ Ridge) x Rise / m = (1000 – 17.5) x 0.466 = 982.5 x 0.466 = 458 1.000 √2

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Lay out of Broken Hip Roof Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Rafter Spacing 300mm 1.489 1.103 0.466 Determine Required Lengths Common Rafter Major Span = 1084 Common Rafter Minor Span = 725 Rise Main Roof = 458 = (½ Span Major – ½ Ridge) x Rise / m = (1000 – 17.5) x 0.466 = 982.5 x 0.466 = 458 1.000 √2

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Lay out of Broken Hip Roof Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Rafter Spacing 300mm 1.489 1.103 0.466 Determine Required Lengths Common Rafter Major Span = 1084 Common Rafter Minor Span = 725 Rise Main Roof = 458 Rise Minor Roof = = (½ Span Minor – ½ Ridge) x Rise / m = (675 – 17.5) x 0.466 = 657.5 x 0.466 = 306 1.000 √2

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Lay out of Broken Hip Roof Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Rafter Spacing 300mm 1.489 1.103 0.466 Determine Required Lengths Common Rafter Major Span = 1084 Common Rafter Minor Span = 725 Rise Main Roof = 458 Rise Minor Roof = 306 1.000 √2

Lay out of Broken Hip Roof Roof Pitch = 25⁰ To develop other Roofing Members we need to determine the plan length first Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 We recall that all hips & valleys bisect corners. In this building it means that they are at 45⁰.

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Lay out of Broken Hip Roof Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Rafter Spacing 300mm 1.489 1.103 0.466 Determine Required Lengths Common Rafter Major Span = 1084 Common Rafter Minor Span = 725 Rise Main Roof = 458 Rise Minor Roof = 306 Hip Length Major Span = Plan Length Crown End Rafter x Hip length/m = (1000 – 17.5) x 1.489 = 982.5 x 1.489 = 1.463 1.000 √2

Hip Rafter – Major Span Plumb Cut 1.489 1.103 0.466 1.000 √2 Plumb Cut

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Lay out of Broken Hip Roof Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Rafter Spacing 300mm 1.489 1.103 0.466 Determine Required Lengths Common Rafter Major Span = 1084 Common Rafter Minor Span = 725 Rise Main Roof = 458 Rise Minor Roof = 306 Hip Length Major Span = 1.463 Hip Length Minor Span = = Plan Length Crown End Rafter x Hip length/m = (0.675 – 17.5) x 1.489 = 657.5 x 1.489 = 979 1.000 √2

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Lay out of Broken Hip Roof Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Rafter Spacing 300mm 1.489 1.103 0.466 Determine Required Lengths Common Rafter Major Span = 1084 Common Rafter Minor Span = 725 Rise Main Roof = 458 Rise Minor Roof = 306 Hip Length Major Span = 1.463 Hip Length Minor Span = = Plan Length Crown End Rafter x Hip length/m = (0.675 – 17.5) x 1.489 = 657.5 x 1.489 = 979 1.000 √2 Valley is the same as the hip

Hip Rafter – Minor Span Plumb Cut 1.489 1.103 0.466 1.000 √2 Plumb Cut As Major & Minor Span are the same pitch the plumb cuts must be the same

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Lay out of Broken Hip Roof Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Rafter Spacing 300mm Determine Centreline Length Common Rafter Major Span = 1084 Common Rafter Minor Span = 725 Rise Main Roof = 458 Rise Minor Roof = 306 Hip Length Major Span = 1.463 Hip Length Minor Span = 979 1st Creeper Major Plan Length = ½ Span – Spacing + Correction = 1000 – 300 + (1.414 x -17.5 + 17.5) = 693 x Rafter Length / m = 693 x 1.103 = 764 1.489 1.103 0.466 1.000 √2 Note these measurements are directional as it goes back towards the Top Plate it must be a negative

Creepers– Major Span Plumb Cut 1.489 1.103 0.466 1.000 √2 Plumb Cut Creepers are the same pitch as the Common Rafters. They must have the same Plumb Cut

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Lay out of Broken Hip Roof Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Rafter Spacing 300mm Determine Centreline Length Common Rafter Major Span = 1084 Common Rafter Minor Span = 725 Rise Main Roof = 458 Rise Minor Roof = 306 Hip Length Major Span = 1.463 Hip Length Minor Span = 979 1st Creeper Major = 764 1st Creeper Minor = 406 Plan Length = ½ Span – Spacing + Correction = 675 – 300 + (1.414 x -17.5 + 17.5) = 368 x Rafter Length / m = 368 x 1.103 = 406 1.489 1.103 0.466 1.000 √2

Creepers– Minor Span Plumb Cut 1.489 1.103 0.466 1.000 √2 Plumb Cut Creepers are the same pitch as the Common Rafters. They must have the same Plumb Cut

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Lay out of Broken Hip Roof Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Rafter Spacing 300mm Determine Required Lengths Common Rafter Major Span = 1084 Common Rafter Minor Span = 725 Rise Main Roof = 458 Rise Minor Roof = 306 Hip Length Major Span = 1.463 Hip Length Minor Span = 979 1st Creeper Major = 764 1st Creeper Minor = 406 1st Valley Creeper = 698 Plan Length = ½ Span + Valley Correction – ½ Ridge = 675 - (1.414 x -17.5 + 17.5) – 17.5 = 633 x Rafter Length / m = 633 x 1.103 = 698 1.489 1.103 0.466 1.000 √2

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Edge Bevel for Valley Creepers Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 What Triangle forms the Bevel

Crippled or Valley Creepers Plumb Cut 1.489 1.103 0.466 1.000 √2 Plumb Cut Creepers are the same pitch as the Common Rafters. They must have the same Plumb Cut

Lay out of Broken Hip Roof Roof Pitch = 25⁰ To develop other Roofing Members we need to determine the plan length first Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Determine Crippled Centring Rafter

Lay out of Broken Hip Roof Roof Pitch = 25⁰ To develop other Roofing Members we need to determine the plan length first Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Determine Crippled Centring Rafter We recall that all hips & valleys bisect corners. In this building it means that they are at 45⁰.

Lay out of Broken Hip Roof Roof Pitch = 25⁰ To develop other Roofing Members we need to determine the plan length first Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Determine Crippled Centring Rafter Hips at 45° 1000-675 = 325 ½ Span Major – ½ Span Minor

Lay out of Broken Hip Roof Roof Pitch = 25⁰ To develop other Roofing Members we need to determine the plan length first Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Determine Crippled Centring Rafter We recall that all hips & valleys bisect corners. In this building it means that they are at 45⁰. Therefore where the Broken Hip intersects the Ridge Minor Span must be 325mm from the Centreline of the Ridge Major Span

Lay out of Broken Hip Roof Roof Pitch = 25⁰ To develop other Roofing Members we need to determine the plan length first Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Determine Crippled Centring Rafter Both Hips at 45° 1000-675 = 325 ½ Span Major – ½ Span Minor

Lay out of Broken Hip Roof Roof Pitch = 25⁰ To develop other Roofing Members we need to determine the plan length first Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Determine Crippled Centring Rafter = (½ Major Span – ½ Minor Span) x 2 Or = Major Span – Minor Span This must be 2x This

Lay out of Broken Hip Roof Roof Pitch = 25⁰ To develop other Roofing Members we need to determine the plan length first Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Determine Crippled Centring Rafter As the valley is at 45⁰ the intersection with the valley must be a further 325mm

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Lay out of Broken Hip Roof Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Rafter Spacing 300mm Determine Required Lengths Common Rafter Major Span = 1084 Common Rafter Minor Span = 725 Rise Main Roof = 458 Rise Minor Roof = 306 Hip Length Major Span = 1.463 Hip Length Minor Span = 979 1st Creeper Major = 764 1st Creeper Minor = 406 1st Valley Creeper = 698 Crippled Centring Rafter = 689 Plan Length = Major Span – Minor Span + Valley Correction – ½ Ridge = 2000 – 1350 + (1.414 x -17.5 + 17.5) – 17.5 = 625 x Rafter Length / m = 625 x 1.103 = 689 1.489 1.103 0.466 1.000 √2

Crippled Centring Rafter Plumb Cut 1.489 1.103 0.466 1.000 √2 Plumb Cut Crippled Centring Rafter is the same pitch as the Common Rafters. It must have the same Plumb Cut

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Edge Bevel for Crippled Centring Rafter Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 What Triangle forms the Bevel

Simple Bevel Development From Previous Plumb Bevel Rafter Level Bevel Rafter Edge Bevel Creeper Edge Bevel Purlin Plumb Bevel Hip Level Bevel Hip Edge Bevel Hip Face Bevel Purlin

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Every Valley Creeper must have an opposing creeper Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Every Valley Creeper must have an opposing creeper Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Every Valley Creeper must have an opposing creeper Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Every Valley Creeper must have an opposing creeper Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 From previous calculations we determined the following

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Every Valley Creeper must have an opposing creeper Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Centreline length is the same as distance from the gathering point

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Every Valley Creeper must have an opposing creeper Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 To determine true length Long Pt Centreline length 325 +/- Long Point Correction -7.5 (-17.5 x 1.414 + 17.5) Deduct ½ Ridge 17.5 Plan Length = 325 + -7.5 - 17.5

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Lay out of Broken Hip Roof Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Rafter Spacing 300mm Determine Required Lengths Common Rafter Major Span = 1084 Common Rafter Minor Span = 725 Rise Main Roof = 458 Rise Minor Roof = 306 Hip Length Major Span = 1.463 Hip Length Minor Span = 979 1st Creeper Major = 764 1st Creeper Minor = 406 1st Valley Creeper = 698 Crippled Centring Rafter = 689 Crippled Creeper Matching = 331 Plan Length = ½ Span Major – ½ Span Minor + Valley Correction – ½ Ridge = 1000 – 675 + (1.414 x -17.5 + 17.5) – 17.5 = 300 x Rafter Length / m = 300 x 1.103 = 331 1.489 1.103 0.466 1.000 √2

Crippled Matching Rafter Plumb Cut 1.489 1.103 0.466 1.000 √2 Plumb Cut Crippled Matching Rafter is the same pitch as the Common Rafters. It must have the same Plumb Cut

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Lay out of Broken Hip Roof Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Rafter Spacing 300mm Determine Required Lengths Common Rafter Major Span = 1084 Common Rafter Minor Span = 725 Rise Main Roof = 458 Rise Minor Roof = 306 Hip Length Major Span = 1.463 Hip Length Minor Span = 979 1st Creeper Major = 764 1st Creeper Minor = 406 1st Valley Creeper = 698 Crippled Centring Rafter = 689 Crippled Creeper Matching = 331 Creeper Shortening = 331 Rafter Spacing x Rafter Length / m = 300 x 1.103 = 331 1.489 1.103 0.466 1.000 √2

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Lay out of Broken Hip Roof Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Rafter Spacing 300mm As both spans are the same pitch they are SIMILAR so Creeper Shortening is the same for both spans Determine Required Lengths Common Rafter Major Span = 1084 Common Rafter Minor Span = 725 Rise Main Roof = 458 Rise Minor Roof = 306 Hip Length Major Span = 1.463 Hip Length Minor Span = 979 1st Creeper Major = 764 1st Creeper Minor = 406 1st Valley Creeper = 698 Crippled Centring Rafter = 689 Crippled Creeper Matching = 331 Creeper Shortening = 331

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Lay out of Broken Hip Roof Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Rafter Spacing 300mm So the roofing members we have previously looked at are determined the same way Determine Required Lengths Common Rafter Major Span = 1084 Common Rafter Minor Span = 725 Rise Main Roof = 458 Rise Minor Roof = 306 Hip Length Major Span = 1.463 Hip Length Minor Span = 979 1st Creeper Major = 764 1st Creeper Minor = 406 1st Valley Creeper = 698 Crippled Centring Rafter = 689 Crippled Creeper Matching = 331 Creeper Shortening = 331

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Edge Bevel for Crippled Centring Rafter Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Edge Bevel for Crippled Centring Rafter is the CREEPER EDGE BEVEL The same is for Valley Creepers Crippled Creepers

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 Edge Bevel for Crippled Centring Rafter is the CREEPER EDGE BEVEL The same is for Valley Creepers Crippled Creepers It follows that all the The purlin bevels are The same as the hip end

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Determine Centreline Length Broken Hip Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Broken Hip Run 325 x 1.414 = 460 Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 1.489 1.103 0.466 1.000 √2 Determine Plan Centreline Length = 325

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Broken Hip Run 325 x 1.414 = 460 Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 1.489 1.103 0.466 1.000 √2 Determine Plan Centreline Length = 325 Centreline True Length = Plan Length x Hip Rafter / m = 325 x 1.489 = 484

Broken Hip Edge Correction At Base

Broken Hip Edge Correction At Base

Valley at Base of Broken Hip

Valley at Base of Broken Hip

Broken Hip Edge Correction at Top

Broken Hip Edge Correction at Top

Lay out of Broken Hip Roof Roof Pitch = 25⁰ Plumb cut is the same as the hip Edge Bevels are the same as the hip Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35 1.489 1.103 0.466 1.000 √2

Lay out of Broken Hip Roof Roof Pitch = 25⁰ With the more complex roof a roof is. It is important to plan & determine as much of the roof offsite that you can Rafter 90 x 35 @ 450 c to c Hip Rafters 140 x 35 Ridge 140 x 35