While both replies are technically correct, Ganhaar provided the most useful answer here. Each member length is half the full circumference (2*Pi*Radius/2) of the dome's full sphere, so Member_Length=Pi*Radius, where Radius is the same as this half-dome height. Throw Pi on the other side of this equation and you get Dome_Height=Member_Length/Pi, where Pi is a smidge over 3, so rounding down length/3 is a good enough height approximation. If you're calculating for accurate standing head clearance at center, then divide the total half-circumference member length (add total joint increases to each length, about 12.06m total here) by Pi directly on any decent calculator, and subtract the outer radius of the conduit(s) at center intersection (about 30mm here) to account for dome thickness (1...see more »While both replies are technically correct, Ganhaar provided the most useful answer here. Each member length is half the full circumference (2*Pi*Radius/2) of the dome's full sphere, so Member_Length=Pi*Radius, where Radius is the same as this half-dome height. Throw Pi on the other side of this equation and you get Dome_Height=Member_Length/Pi, where Pi is a smidge over 3, so rounding down length/3 is a good enough height approximation. If you're calculating for accurate standing head clearance at center, then divide the total half-circumference member length (add total joint increases to each length, about 12.06m total here) by Pi directly on any decent calculator, and subtract the outer radius of the conduit(s) at center intersection (about 30mm here) to account for dome thickness (12.06m/Pi - 0.03m ~= 3.809m or 12.496ft). More precise parts measurements will obviously give you a more accurate height estimate. If you only care about accuracy within ~5% due to bendy parts and slippy joints, then you can see here how length/3 is still good enough.

While both replies are technically correct, Ganhaar provided the most useful answer here. Each member length is half the full circumference (2*Pi*Radius/2) of the dome's full sphere, so Member_Length=Pi*Radius, where Radius is the same as this half-dome height. Throw Pi on the other side of this equation and you get Dome_Height=Member_Length/Pi, where Pi is a smidge over 3, so rounding down length/3 is a good enough height approximation. If you're calculating for accurate standing head clearance at center, then divide the total half-circumference member length (add total joint increases to each length, about 12.06m total here) by Pi directly on any decent calculator, and subtract the outer radius of the conduit(s) at center intersection (about 30mm here) to account for dome thickness (1...see more »While both replies are technically correct, Ganhaar provided the most useful answer here. Each member length is half the full circumference (2*Pi*Radius/2) of the dome's full sphere, so Member_Length=Pi*Radius, where Radius is the same as this half-dome height. Throw Pi on the other side of this equation and you get Dome_Height=Member_Length/Pi, where Pi is a smidge over 3, so rounding down length/3 is a good enough height approximation. If you're calculating for accurate standing head clearance at center, then divide the total half-circumference member length (add total joint increases to each length, about 12.06m total here) by Pi directly on any decent calculator, and subtract the outer radius of the conduit(s) at center intersection (about 30mm here) to account for dome thickness (12.06m/Pi - 0.03m ~= 3.809m or 12.496ft). More precise parts measurements will obviously give you a more accurate height estimate. If you only care about accuracy within ~5% due to bendy parts and slippy joints, then you can see here how length/3 is still good enough.

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