Also, sometimes it looks like the wall join each other, but it is the actual reference lines that must touch to close the polygon.
Turn on the reference lines (on screen display option) and make sure all the wall trim.
It probably is just the renovation settings though.
As mentioned a zone can only work on walls that have the same renovation setting as the zone.
So if you have a mix of existing and new walls, even though they form a closed polygon, when you look at just the existing or new walls, there may be gaps (again it is the reference lines that must touch).
Barry.
One of the forum moderators.
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