## ExoticInspirit one year ago Hi I need help with my attic measurements for a real house

1. exoticinspirit

|dw:1438732171291:dw| Given this info, how do I find these lengths so I can know how many shingles to buy

2. exoticinspirit

@ganeshie8 ?

3. mathmate

It depends on how high the attic above it's support. Did you make that measurement?

4. exoticinspirit

3 ft is the height of the attics roof if youre talking about the house , i dont get how that will help

5. exoticinspirit

basically the height of the whole attic (instead of saying attics roof_ because the attic is the roof itself

6. exoticinspirit

@Hero @Michele_Laino

7. mathmate

The height definitely changes the area of shingles. A steeper roof requires more shingles than a near flat roof. Here you have a relatively flat roof, and you would need about 11-14% more than the plan area, so a total of 13*22*1.14=326 sq. ft. Allow extra for the overlaps at the crest, ridges, and return around the bottom. Note that this is an estimate based on the measurements. Actual area depends on how you measure and how you work. Do not expect this to be accurate to the shingle or anywhere near that.

8. exoticinspirit

Yes but I just want the lengths for those two hips for the roof am i just supposed to multiply the height and length

9. exoticinspirit

I tried by multiplying and I got 39 ft a half of that would be 19.5 ft would that be the length of one hip of the roof

10. exoticinspirit

I need this done by toady if youre still available to help @mathmate

11. exoticinspirit

@nincompoop ?

12. exoticinspirit

hey

13. mathmate

Are you covering the whole roof with shingles?

14. mathmate

There is not enough information given to calculate individual pieces if 3' is only the height. But I estimated the total area of the sloping roof for you as long as you're covering the whole roof. However, you have to make adjustments for overlaps and wastage.

15. exoticinspirit

yes with shingles and I really don't have information because the roof is not yet created

16. mathmate

As I said, I have estimated the area of the sloping roof, but you will have to make adjustments for wastage and overlaps. Perhaps it would be safe to add 15 sq. ft for the two ends which have a steeper slope, so that makes about 340 sq. ft. + wastage+overlap.

17. exoticinspirit

yeah i have no experience in this kind of construction work just trying to help out a close friend with their house and they saidd they needed the measurements for the two roof stands/hips given that information

18. exoticinspirit

ok well i really appreciate your help :)!! THANKS

19. mathmate

You're welcome! :)

20. exoticinspirit

also let me add one more thing , so it really shouldn't be done with math right i should choose the right lengths that fit

21. UnkleRhaukus

|dw:1438743318969:dw|

22. UnkleRhaukus

|dw:1438743491221:dw|

23. UnkleRhaukus

wait a minute, is it meant to be a 3D diagram ?

24. UnkleRhaukus

|dw:1438743669340:dw|??

25. UnkleRhaukus

|dw:1438743754692:dw|???

26. exoticinspirit

wow this is awesome @UnkleRhaukus

27. exoticinspirit

im still a bit confused about the hip rafter length though, you get what im saying? Should I decide the length of the rafter as x/12 after i find the area of the house?

28. UnkleRhaukus

|dw:1438744883716:dw|

29. UnkleRhaukus

oh....

30. UnkleRhaukus

is it more like this |dw:1438745084061:dw| ?

31. UnkleRhaukus

|dw:1438745240852:dw|

32. exoticinspirit

actually sorry for the misunderstanding but instead of saying roof rafter it isnt like that but the roof pitch i meant

33. UnkleRhaukus

We need to be exactly sure what the diagram looks like

34. exoticinspirit

im not good with this topic its my first time so i only have a sketch of it not a 3d diagram and i just want the measurements for the two roof legs that make it rise really im stuck on how to figure it out

35. exoticinspirit

|dw:1438745579825:dw|

36. exoticinspirit

lol your profile picture seems like half of a roof pitch

37. UnkleRhaukus

lol

38. UnkleRhaukus

* Can you mark all the 90° angles

39. exoticinspirit

|dw:1438745909503:dw|

40. UnkleRhaukus

are there some more right angles you can mark? i am still having trouble interpreting the diagram

41. exoticinspirit

um maybe 4 more on the flooring of the attic in all corners why

42. UnkleRhaukus

Use pythagorus to find the missing sides of the rightangled triangles

43. exoticinspirit

I thought you just had to do this Find the surface area 2(wl+lh+hw) So 2(22x13)+(13x3)+(3x22)=457 ft^2 and with this i can find the length of the roof pitch OR do I just make up the roof pitch for whichever is safe for the roof. Also I did try the pythagorean theorem if thats what u mean i got 19.5

44. UnkleRhaukus

2(wl+lh+hw) is the surface area of a rectangular prism, so that wont work

45. exoticinspirit

oh.. facepalm- the only formula that would work is the Pythagorean for the triangles then yea?

46. UnkleRhaukus

yes |dw:1438747235730:dw|

47. UnkleRhaukus

. . .$c=\sqrt{a^2+b^2}$

48. exoticinspirit

Ok this is what I got c=51.25 square rooted it is 7.15 so is that it? so if I were to buy this http://www.homedepot.com/p/Owens-Corning-Oakridge-Onyx-Black-Laminate-Shingles-32-8-sq-ft-per-Bundle-HK01/205655927 it covers 32.8sq ft This is right for my measurements even if its only like 2 ft extra but what would the

49. exoticinspirit

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