Hip & Valley

Hip Valley Roof This is to be used in conjunction with the following plan which can be found here

Is the Roof a True Hip & Valley Roof Spans are equal

Is the Roof a True Hip & Valley Roof Rise will be the same and ridges will meet in the centre

Is the Roof a True Hip & Valley Roof If Spans are not equal ridges will not meet

Is the Roof a True Hip & Valley Roof If Spans are not equal ridges will not meet This part of the roof is still going up

Is the Roof a True Hip & Valley Roof If Spans are not equal ridges will not meet This part of the roof is still going up This part of the roof is going down

Is the Roof a True Hip & Valley Roof To Solve this we have to construct a Broken Hip which is the next roof

Determine The Spans

Every Ridge must have a Span

Determine The Spans Span is tied to the Basis of the Common Rafter Calculation

Determine The Spans Span is tied to the Basis of the Common Rafter Calculation Same Rafters

Determine The Spans Span is tied to the Basis of the Common Rafter Calculation Same Rafters Must be same Span

Hip & Valley Roof STEP 1 -As always Determine the 1 metre triangles -Please review Gable & Hip roofs if you do not know how to do this Rise per 1m of Rafter Plan length Rafter Length per 1m of Rafter Plan length Hip Length per 1m of Rafter Plan length

Hip & Valley Roof STEP 1 -As always Determine the 1 metre triangles -Please review Gable & Hip roofs if you do not know how to do this 1.000√ Pitch 32°

Hip & Valley Roof STEP 1 -As always Determine the 1 metre triangles -Please review Gable & Hip roofs if you do not know how to do this ° Rafter = Plan Length x Rafter per m

Determine Common Rafter Rafter = Plan Length x Rafter per m = (5400 – 9.5) x = Rafter 90 x 450 c to c Ridge 140 x 19 Valley 140 x °

Determine Valley Rafter Valley is determined in the exact same manner as the Hip Rafter Valley Rafter = ½ Span x Hip / m = 2700 x = 4452 The hip is usually measured as per the Hip Rafter. Calculation is only for estimating 5400 Rafter 90 x 450 c to c Ridge 140 x 19 Valley 140 x ° 1.179

Determine Valley Rafter for Estimating Valley is determined in the exact same manner as the Hip Rafter Valley Rafter = (½ Span + O/H )x Hip / m = ( ) x = (Plumb Cut) = 5682 = 5700 Note if Hip is required to be joined you should allow at least 300mm 5400 Rafter 90 x 450 c to c Ridge 140 x 19 Valley 140 x 45 Overhang ° 1.179

Plumb Cut Valley Using Steel Square 5400 Rafter 90 x 450 c to c Ridge 140 x 19 Valley 140 x 45 Overhang ° ÷3

Plumb Cut Valley Pitch Mathematically 5400 Rafter 90 x 450 c to c Ridge 140 x 19 Valley 140 x 45 Overhang ° Tan Pitch° = Rise ÷ Plan Length = ÷ √2 = Inv Tan (0.442) = 23.8° or 23.8° (Note Inv is not mathematical inverse Function but the Calculators Trig inverse

Valley True Length Valley Plan Length = ½ Span – ½ Ridge Thickness = 2700 – 17.5 = ½ Span – ½ Ridge Thickness ½ Span = 2700 Ridge 140 x 35

Valley True Length Valley Plan Length = ½ Span – ½ Ridge Thickness = 2700 – 17.5 = True Length = Plan Length x Hip/m = x = 4423 ½ Span – ½ Ridge Thickness ½ Span = 2700 Ridge 140 x 35

Valley Creepers Plan Length = ½ Span – (½ Valley x √2 + ½ Rafter) – ½ Ridge = 2700 – (22.5 x √ ) = 2618 ½ Span = 2700 Ridge 140 x 35 Rafter 90 x 35 Valley 140 x 45

Valley Creepers – 1 st Creeper Plan Length = ½ Span – (½ Valley x √2 + ½ Rafter) – ½ Ridge = 2700 – (22.5 x √ ) = 2618 True Length = Plan Length x Rafter /m = 2618 x = 3087 ½ Span = 2700 Ridge 140 x 35 Rafter 90 x 35 Valley 140 x 45

Valley Creepers – 1 st Creeper Plan Length = ½ Span – (½ Valley x √2 + ½ Rafter) – ½ Ridge = 2700 – (22.5 x √ ) = 2618 True Length = Plan Length x Rafter /m = 2618 x = 3087 Creeper Shortening = Spacing x Rafter Length / m = 450 x = 531 This will be the same as the Hip ½ Span = 2700 Ridge 140 x 35 Rafter 90 x 450 c to c Valley 140 x 45

Valley Creepers – 1 st Creeper Plan Length = ½ Span – (½ Valley x √2 + ½ Rafter) – ½ Ridge = 2700 – (22.5 x √ ) = 2618 True Length = Plan Length x Rafter /m = 2618 x = 3087 Creeper Shortening = Spacing x Rafter Length / m = 531 ½ Span = 2700 Ridge 140 x 35 Rafter 90 x 450 c to c Valley 140 x 45

Valley Creepers – All Creepers Plan Length = ½ Span – (½ Valley x √2 + ½ Rafter) – ½ Ridge = 2700 – (22.5 x √ ) = 2618 True Length = Plan Length x Rafter /m = 2618 x = 3087 Creeper Shortening = Spacing x Rafter Length / m = 531

Valley Creepers Plumb Cut As it is the same pitch as the Rafter it is the same Steel Square

Valley Creeper – Edge Bevel ½ Span Rafter Centreline Length Same as Hip Creeper Ridge