Mik, you have touched on one of my favorite topics - how to construct raised level large scale layouts. While your question was directed towards indoor applications, the variety of replies re. outdoor pikes is always great to see and I'll bet are helpful to a lot of folks.
I have been planning a raised level indoor pike for a few years now and am getting closer to construction. The complicating factor for me is that my wife and I use our 28'x28' basement extensively. We have a library & entertainment center in one side (the stairs to the main floor act as a divider) that houses a 52" HDTV home theater with all the requisite electronics and speakers, and several sections of 6 ft high bookshelves. We have our home office on the other side with desks and file cabinets, the laundry area in the back behind the entertainment area, and the HVAC and HWH along with our storage area is behind the office area. In short - there really isn't any separate place for trains.
So I devised a plan to install a shelf around the entire perimeter of the basement at a height of 54" high from the floor (which is reasonably level). The shelf will vary from 18" deep at the narrowest to 36" deep at the widest point (where my main town will be) with most of it being in the 24" to 28" range. The railroad will be double tracked for the entire perimeter and the rear track will be raised higher than the front track, except where the crossover between the two is located.
My plan is to use wall-mounted heavy duty shelf brackets such as the 22" model from Knape and Vogt, (or a similar model made by Stanley) which they claim will hold 1,000 lbs. per pair when mounted per their instructions (which I have not yet seen). My plan is to lag the brackets into the 2x4 studs (24" O.C.) that I will use to frame the inside of the exterior basement walls (which are poured concrete) in which I'll run the electric, cable and telephone lines, and attach pre-finished wood or composite panelling. I have not settled on exactly what I will use for shelving; 3/4"plywood was my initial choice because I did not want it too thick that it raised the surface of the RR too much higher and affect my easy access (for construction and maintenance) and viewing. If I used an open frame type of construction (using 1x4s), it would make grade construction easier but could become too high. I'll use a lot of foam for scenery construction and even with all of the trains and buildings I plan to use (already have them), I don't see where I'll even get close to the weight rating of the shelf brackets.
The chosen height and depth of shelving allows me to use the space underneath for all of the activities mentioned above. When seated at my desk, a 54" high shelf will not interfere, and even provides a place to mount a task light over the desk. The file cabinets all fit under the 54" height; the large widescreen TV fits under the shelf and still permits viewing at eye level when seated in our recliners or on the sofa. The 6 ft library shelves will have to be replaced by units that will fit under the 54" height but that is no problem - they are old and were cheap anyway. The problem areas are the electrical service panel (load center), the utility sink in the back (we stand at that sink so 54" will not work there), the rear exterior door (to an areaway) which will require a lift out bridge section, and the furnace / hot water heater. At 54" high, access to the load center (located in one corner) will be restricted unless I curve the shelf away from it, which I need to do anyway to handle the 6.5 and 8 ft diameter curves. In front of the furnace & HWH I figure I can build some kind of roll-away sections that can be removed should something more than changing a filter be required at the furnace.
Al
