A grain storage bin includes a cylindrical wall formed by a plurality ofpanels arranged in rows with a bottom edge of a first row bolted to a top edgeof asecond lower row. At each joint the bottom edge of the first upper row isoverlappedwith and outside of the outer surface of top edge of the second lower row andthebottom edge is fastened to the top edge by bolts carrying spacers as to definea firstchannel along the joint for passage of air. A cover strip overlies the channelandextends from an upper edge of the strip at the inner surface of the firstpanel abovethe channel to a lower edge of the strip which is fastened to the top edge soas todefine a second channel so that air can pass between the interior and theexteriorthrough the first and second channels while the particulate material ispreventedfrom escaping through the first channel by the cover strip.
