HO scale (1:87) is the most common choice for model railroad track plans in North America, and it is popular in many other countries as well. Its popularity means a huge choice of locomotives, rolling stock, track, and ready-made plans. This guide helps you sort HO plans by the space you have and the experience you bring.
Why HO is popular for track plans
HO sits in a useful middle ground. Models are large enough to detail and handle comfortably, yet small enough to build an interesting layout in a spare room, a basement corner, or on a single sheet of plywood. Track, turnouts, and accessories are available from many manufacturers, so plan libraries and software are well stocked with HO parts.
Note that British modelers often use OO gauge track with similar plans. Many free plan sites accept both, but check the details of your own equipment.
HO plans by space
Small and table-top plans
Small HO layouts, sometimes under six or seven feet long, are common for sectional-track starter sets and for compact plans designed around a particular track system. Plan listings in databases often show footprints such as roughly 6.5 by 3.5 feet, using sectional track from a single manufacturer. They are good for learning, but tight curves are common, so long locomotives and passenger cars may not run well.
The 4x8 sheet
The 4x8 foot sheet of plywood is the classic starter footprint, partly because plywood comes in that size. Plans for it are everywhere, with oval-plus-siding designs, figure eights, and designs with branch lines or reverse loops. The trade-offs:
- Radius is limited, so choose shorter locomotives and cars.
- The middle of a 4-foot-wide table is hard to reach, so keep turnouts near edges and plan access for the middle.
- It is hard to hide staging or add scenery depth in so small a space.
Door-sized and shelf plans
Hollow-core doors and narrow shelves offer another way to get started. A shelf layout can run along a wall and use a narrow switching plan with a few industries. These designs often yield more realistic operation than an oval of the same size.
Room-size plans
Bigger rooms allow around-the-wall plans, peninsulas, a lower and upper level, and staging. At this size you need to think about aisle width, door access, and lighting as well as track. For a general review of these footprints, see our guide to model train layouts.
HO plans by skill level
Beginner. Choose a simple loop with one or two sidings and flat track. Start with sectional track or a simple flex-track plan. The goal is reliable running and finishing something.
Intermediate. Add a passing siding, a small yard or industrial area, and a few grades. You may start to use flex track for broader curves and larger turnouts.
Advanced. Plan multiple decks, hidden staging, helixes, or detailed prototype-based track. At this level you will spend more time on the drawing, so read our guide on designing a model railroad track plan.
Common HO plan types
- Simple oval: easy to build and run; not much to do beyond watching trains.
- Figure eight: fits a crossing into a small space and avoids a tight return loop.
- Loop with sidings: adds some switching and train meets.
- Branch line or terminal: a stub-ended plan with a station or small yard, often with continuous running replaced by shunting.
- Switching (shunting) layout: a compact plan of industries, designed for puzzles rather than watching trains pass.
- Mixed double and single track: found in plans for larger tables, offering more variety.
HO planning numbers
These are general guides; always check your manufacturer’s information.
- Scale: 1:87, with track gauge of about 16.5 mm.
- Minimum radius: a common point of difference. Starter sets often use fairly tight curves, but longer locomotives and passenger cars generally run and look better on broader curves. Use the manufacturer’s recommended minimum for your longest equipment.
- Turnouts: No. 4 turnouts are shorter and can suit yards and tight spots; No. 6 or larger usually works better on main lines.
- Grades: the NMRA guide notes that grades over roughly 2% significantly affect locomotive performance.
- Reach: keep turnouts and important track within comfortable reach.
Track systems
Many HO plans are drawn around a specific track system, such as sectional snap-together track or flex track with separate turnouts. Plan listings note the system, and it matters: a plan drawn with one brand may not translate perfectly to another because the curve radii and turnout geometry differ. Check the track listed before you buy. Flex track allows more graceful curves and fits plans to your room, while sectional track is quicker to set up.
Where to get HO plans
Many HO plans are free. The SCARM database, for example, can be filtered by scale and size, and lists details such as dimensions, type of line, era, and track brand. FreeTrackPlans.com has several hundred plans for HO and OO. For a fuller list of sources, see our guide to free model railroad track plans.
Choosing between plans
When you narrow down candidates, ask:
- Does it fit my space, including aisles and doors?
- Do the curves suit the equipment I own or want?
- Can I reach everything?
- Does it offer the kind of running I want: watching, switching, or both?
- Can I finish it in a reasonable time?
Once you have a plan, think about how it will look. Our guide to realistic model train layouts explains how scenery, curves, and compression make a plan look like a real railroad.