I use alot of long, slender beams with thin webs so solid elements are not possible or practical to get 3-4 elements through the thickness. I usually create surface models based off the solid geometry and body delete the solids. My question is though when using mid-plane surfaces you get material thickness overlaps once the FEA figures in shell thickness. Does this create overly ridged areas of the model? Simple case would be say we had an I-beam, the web to flanges would have material overlap.