Stuart,
How much real estate are you devoting to the location of your roundhouse on your switching layout? I just got the engine servicing facility planned out on my layout and I only have room for a single stall enginehouse, so I would like to ask how much room you have for your structure? Roundhouses are cool, but tend to take up space. I had a Heljan (now made for Walthers) 3-stall roundhouse that took up a large part of one corner of one of my modules.
So, after asking about space, I would ask what era you're depicting, modern or transition? That will determine style/type. If you have the space, I would go with jmp833's suggestion of using the Walther's modern roundhouse. Lots of big windows that would show off your fleet as they "rest' in their stalls. If you don't have space, I would suggest a small enginehouse. There are numerous manufacturers who make one or two stall enginehouses that would be perfect for a small industrial switching layout. Are you up for a little kitbashing? There's an article in a back issue of Model Railroader (that I'm still looking for) on how to build a 2 stall brick diesel house using City Classics' warehouse walls, DPM brick walls and strip styrene. I'll be more than happy to photocopy the article and mail it to you if you're interested.
I toyed with the same issue with my facility before I decided that the roundhouse, while cool, would not fit my layout... both in terms of size and setting. I wanted this layout to give the feeling of being on a small branchline in a rural area, so the big, brick, 3-stall roundhouse was done away with (in fact, I dontated it to the model railroad club at the U of Minn.) and I am now planning to use a small, wooden, one-stall enginehouse. Not only does it help aid in the sense of being a lightly used branchline, but I can now fit the enginehouse, sanding facilities, fuel dock, coal bunker, water tower, and ash pit (I model the modern era, but want the feel of history and antiquity by having the old steam-era stuff) in the space that would have been taken up by the roundhouse.
Although, let me ask you this as well... have you considered the option of no roundhouse and just having the uncovered tracks radiating out from the table? I don't know if they still have the table, but when I used to go through LaCrosse (WI) on the Empire Builder, I used to glance over at the CP (or was it the BNSF) shops and saw where the roundhouse used to be, with the tracks still radiating out from a central point, some had locomotives or plows parked on them. Just a thought.
Anyway, I hope it helps you figure out what you want to do. Let us know what you decide.
