Here's a cheap trick that I should have seen long ago.........
The objective is to measure the total roof area as viewed by God - irrespective of storeys, overlap, slope, etc., for the purposes of determining rainwater collection.
Starting with just the roof plan:
1. On a new exclusive layer, draw a 2D polygon round the entire roof, but clear of it.
2. Draw one line from anywhere on the roof across any line on the polygon
3. Put a contour search hatch between the roof and the polygon.
4. L,F4 this layer, and get the area of the unhatched zone by contour search.
The objective is to measure the total roof area as viewed by God - irrespective of storeys, overlap, slope, etc., for the purposes of determining rainwater collection.
Starting with just the roof plan:
1. On a new exclusive layer, draw a 2D polygon round the entire roof, but clear of it.
2. Draw one line from anywhere on the roof across any line on the polygon
3. Put a contour search hatch between the roof and the polygon.
4. L,F4 this layer, and get the area of the unhatched zone by contour search.
Nick Pyner
Dee Why Beach NSW
Dee Why Beach NSW