Types of train barns

I'm going to attempt making a three track engine house out of foam core and brick paper. Gatorboard might be good too although more expensive than foamcore.

Are you planning 3 individual entrances or one large entrance. 

Three entrances. I'm devising a mechanical way to open and close those doors from a knob on the fascia board. I've described this project on my structure thread, but here's the design: The overall length is 41-3/8" (big enough to fit a Pennsy S1). 

The door mechanism will either use a flexible brake cable or two-cable Pull-Pull rudder controls. I'm leaning towards the pull-pull system since it's always in tension. All the links will be typical model RC quik-clips or ball and socket connectors. All mechanism will be under the layout. This could be done with an RC servo, but I thought it would end up costings more. It could be controlled remotely at the control panel, but I'm not sure this advantage is strong enough.

I'm collecting materials for this and should be in production sometimes during this year. I've got lots and lots of work to do and a pile of waiting projects, but this one is important to me. I put together an initial paper design study. It quickly showed the need to be BIGGER.

If I wanted an engine house, I would contact Alan Graziano (a Forum member). He has done outstanding work in this regard and modified one of his station shed designs to produce a Sante Fe engine house for Popsrr.

Trainman2001 - Thank you very much for those images.  Your "moving doors" plan sounds great.  I am not in that league.  This will be my first scratch structure. When you said it needs to be bigger are you talking about the dimensions on the front or longer ... both?

You're welcome. Actually both dimensions. Longer to accommodate the engines' length and to include the bumpers within the structure, and wider for more realistic spacing and then I added the machine shop. I have open space on the near side of that site so the machine shop made a good addition. Unfortunately, and you can see in the cut-away, the 3.5" track spacing of my yard leaves very little "workspace" between the tracks. When you use Ross #4 switches in the ladder formation, you get perfectly aligned tracks at 3.5" separation which looks great in the yard. What that really means is no commercially available engine houses can be used without completely rebuilding them.

Yes, I see what you mean.  I am using Lionel fastback 036 switches which requires about 6 inches. 

Here's another look taken from RRTrack's 3d viewer. Most of the buildings in this image are simply placeholders, but the engine house is correctly sized.

Looks great!