I found this comment from Vinny on a forum at this link: https://pinkfishmedia.net/forum/threads/record-and-cd-storage.282913/
“Back in the days of cosy "record shops" (pre-90's, or thereabouts), most seemed (in my area at least) to use Arjay racks for everything - singles, LPs and cassettes - materials were chosen to provide maximum storage with minimal space given to the materials used to build the racks - so way, way more LPs per sq. m. of wall space than anything current. The company were shop-fitters but catered for the home hi-fi nut down to very small units. They had permanent ad's in all the music press, even after they changed ownership/name. They are long since gone, very, very sadly, but I have bought units via Ebay, plus purchases while they were in business, and have Arjay racking for something like 2,500 LP,s.”
“Back in the days of cosy "record shops" (pre-90's, or thereabouts), most seemed (in my area at least) to use Arjay racks for everything - singles, LPs and cassettes - materials were chosen to provide maximum storage with minimal space given to the materials used to build the racks - so way, way more LPs per sq. m. of wall space than anything current. The company were shop-fitters but catered for the home hi-fi nut down to very small units. They had permanent ad's in all the music press, even after they changed ownership/name. They are long since gone, very, very sadly, but I have bought units via Ebay, plus purchases while they were in business, and have Arjay racking for something like 2,500 LP,s.”