Velux windows on low pitch roof
- Thread starter SJRSJR
- Start date
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do you remember doing trigonometry at school, particularly the bit about SOHCAHTOA?
^woody^ said:
i think he must have been
sin= opposite over hypotenuse
cosine= adjacent over hypotenuse
tangent = opposite over adjacent.
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lol. That is some memory feat to remember.
I just about recall A Red Indian Thought He May Eat Toffees In Class - but can't remember if it was from maths or english lessons
3,4,5 seems to cover it all nowadays though
I just about recall A Red Indian Thought He May Eat Toffees In Class - but can't remember if it was from maths or english lessons
3,4,5 seems to cover it all nowadays though
You can get a rough idea of the pitch is to use a spirit level, put the spirit level on the roof and pack it out one end of the level until the bubble is in the middle then you may get a sliding bevel underneath the level then transfer onto the protracter
the roof is a big triangle. split the triangle in half at the ridge.
measure the upright distance (x)
measure the horizontal distance
x divided by y.
if the roof is less than 45 degrees you will end up with a number less than 1.
inverse or negative tangent (-tan) this number and it will give you your pitch in degrees.
measure the upright distance (x)
measure the horizontal distance
x divided by y.
if the roof is less than 45 degrees you will end up with a number less than 1.
inverse or negative tangent (-tan) this number and it will give you your pitch in degrees.
Maybe for some, but I seem to have a reason to use sohcahtoa at least once a week.^woody^ said:
That's only useful for confirming right-angles - no use when you're working out a fall, gradient, or many other problems...3,4,5 seems to cover it all nowadays though
Softus said:That's only useful for confirming right-angles - no use when you're working out a fall, gradient, or many other problems...3,4,5 seems to cover it all nowadays though
agree.
pythagarus's theory is useful for squaring up buildings, in other words finding out what the diagonal measurement is, armed only with the lengths of the two 'other' sides.
3 sq= 9
4sq = 16
16+9 = 25. sq root of 25 = 5
as Softus says, only useful with right angle triangles.
edited. sorry Softus.
are you aware your username is an anagram of tofu ss. sieg heil.
are you aware your username is an anagram of tofu ss. sieg heil.
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