You need doors to warm the place up.
Brent
"All of the world's problems are the result of the difference between how we think and how the world works."
I recall my first visit to Florida and being surprized at how many "open-air" structures there were.
Here's a view of an Atlantic Coast Line, Lakeland, Florida, roundhouse sans doors:
Atlantic Coast Line, 1947 by Fred Clark, Jr., on Flickr
In fact, there isn't much in the way of walls, either.
Good Luck, Ed
I'm with Jim, if your modeling a north country railroad, you want doors, even if your time period is summer time, as I do, you need to show that doors are there.
Mike.
My You Tube
It dosen't seem to be very common, but it's not unheard of. Here are several examples: https://commons.wikimedia.org/wiki/Category:Roundhouses_in_the_United_States#/media/File:Bob_Julian_Roundhouse_NC_Transportation_Museum.jpg
https://commons.wikimedia.org/wiki/Category:Roundhouses_in_the_United_States#/media/File:Locomotive_715_on_Turntable,_Roundhouse,_Texas_and_Pacific_Railway_Company_(16289058891).jpg
https://commons.wikimedia.org/wiki/Category:Roundhouses_in_the_United_States#/media/File:Locomotive_715_on_Turntable,_Tender_Wheels,_Texas_and_Pacific_Railway_Company_(12775960815).jpg
I hope this helps. Happy building!
Doorless ones might not be good in northern areas! The DM&IR roundhouse in Proctor, MN has roll-up doors.
Modeling BNSF and Milwaukee Road in SW Wisconsin
I have seen many photos of both actual and modeled roundhouses. Many of them have doors and quite a few of them are without doors. I am scratchbuilding a 5 stall roundhouse and am wondering how realistic it would be to not have doors. Is a doorless roundhous more prototypical in certain geographical areas? What variables were taken into account in the decision to have/not have doors in the construction of a protypical roundhouse? All input will be greatly appreciated.
Thanks
wdcrvr