Many years ago...after having a 'Contractor's Corner' representative at a well-known local home improvement chain store respond to my 'Do you have...?' inquiry with: "What's Homasote?"...I went to a local lumber mill that has a 100-year history in our city. They, of course, were well versed in Homasote. However, there were several caveats to procuring it from them.
First, and most importantly, they do not typically stock it. The reason is quite simple. Because it is essentially a 'paper' (cellulose) product, it MUST be stored in a climate-controlled environment. The call for Homasote is so low, so random, they cannot afford to store a quantity of it in their only relatively small climate-controlled facility. Which leads to the next most significant problem...
Unless you are ordering a significant quantity of full sheets of Homasote, they cannot meet the minimal quantity requisite from either the manufacturer or the freight shipper. At that time, anyway, a full stack of Homasote sheets was in a factory-wrapped package, requiring enclosed trailering, which often was not a full-load proposition for a shipper. Rates were/are accordingly, applied to the per-sheet price, of course.
Then, too, all of the above might result in long lead times to receive an order. They apparently had developed some information about other regional mills and stores that purveyed Homasote--and similar construction materials having like caveats. If it was acceptable to you, the buyer, for your minimal quantity of full sheets and timing not being critical, they would inquire of that list of regional suppliers to see if there might be a source within 'reasonable' driving distance...and get back to you...in a few days...hopefully. Safe transport therefrom would usually be up to the buyer.
And, no returns of full sheets...period.
IOW, to the construction material retailer pro-in-the-know, I got the feeling that, although Homasote is a unique, sometimes useful material (we're NOT talking about being market-limited to model railroad builders/enthusiasts here!) in the trade, it's a bit of a PITA for them to deal in.
Back then, I gave up the idea of using it. Too much trouble for the expense. And, besides, I was in 'the dark side' of the HObby. Noise reduction was actually quite trivial a problem in the scheme of things...IMHO, of course.
Fast forward a bunch of years ...
Well, more recently we have a couple of Menard's outlets locally. They do, indeed, stock/sell Homasote (Thank you, Mr. John Menard, a model railroad hobbyist!). Typically sold in half-sheets. And their stores are adequately climate controlled for proper storage. Not a national solution for the hobbyist, but a growing regional one.
FWIW and from my own experience.
