there shouldn't be a problem. the following is done with SEO's all the way (walls>roofs and slab>roofs). i used 'subtraction
with upwards extrusion
.
one question: are you performing these operations in the section window? and if so, are you actually rebuilding the model after your SEO's? (try doing it in the 3D window (marquee a 'sectional' area through the building) - it's much easier!)
~/archiben
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