<-Back

Yurt Details:

Calculator
Diamater: 18Ft
Wall Height: 5Ft
Center Height: 7.81ft
Wheel Diamater: 4ft
Roof Angle: 25°
Rafters: 40

Wall Material: Sunbrella 10oz Duck Canvas
Roof Material: Sunbrella 10oz Duck Canvas
Floor Material: TBD – Thinking drop cloth

General:
total circumference c = 56.53ft
floor area Afloor = 245.5ft2
total volume Vtotal = 142.163
Wall / Khana:
spacing of roof poles & khana w = 1.41ft,
length of khana lath lkhana = 6.96ft,
spacing between holes wkhana-holes = 1ft,
total 7 holes (extra 0.39ft left),	with αkhana = 90° angle
total of apprx. nlaths = 95 khana laths required,
gives nkhana-sections = 2 khana-sections,	when lkhana section = 25ft
Roof Poles / Uni:
Roof pole length lpole = 7.76ft / 236.47cm, (add additional length for entering the crown-wheel / toono 3-4cm and the other end with cord 2-3cm, total e.g. 6cm)
angle between each pole αpoles = 9°,
space between poles at the roof/crown wheel wwheel = 3.72 in / 9.42cm

Roof Canvas

In order to calculate the angle α_cutoff I simply calculate both circumferences, based on d_roof and d, and then substract the later from the first, this is the length which is left and needs to be cut away:
α_cutoff = (d_roof * π – d * π) * 360 / (d_roof * π)
w_cutoff = sin(α_cutoff/2) * l_roof * 2

Therefore

lroof = 9.93ft /302.67cm,

droof = 19.86ft / 605.34cm,

αcutoff = 33.72 °,

wcutoff = 5.76ft / 175.54cm,

A_roof = 74.61ft² e.g. square canvas of 17.65 x 17.65 ft, apprx. 20.37ft² left over.

Lanewise

Use multiple lanes (common way to get canvas) as indicated to compose the shape:
n_{roof lanes} = d_roof / w_lane (and round up)
l_{tot lanes} = d_roof * n_{roof lanes}

You can calculate more exact (approximate the circle without tilt cutoff α_cutoff):

w_lane 5ft, w_roofextra 1ft,

5 lanes of 21.85ft x 5 ft

Total length as one lane: ~110ft

Wall Canvas
This is rather simple, it’s rectangular, and c (circumference) times h of the lattice wall / khana. With your numbers, the wall canvas is 56.53 ft X 5ft.

Best you choose w_lane the same as h, then you can use one lane for the entire wall canvas; otherwise you require to sew lot’s of vertical lanes together to achieve h, with your w_lane you do 1 lane for the entire wall canvas.

You may substract the door width (discussed later in more detail), but I recommend you plan with extra length, it’s easier to cut than add more canvas later. I used 10m long sections, attached short cords in order to bind it to the main rope, you can also bind to the roof-poles.

Total Canvas

Total canvas of apprx. 166ft or  55.3 yds