If your layout features roads you’ll want accurate widths for them, why go to all the trouble of making wonderful looking track and scenery only to ruin it with naff roads?
Would you believe there are 247,100 miles of road in the UK. I didn’t. But that’s the figure from Department of Transport for 2019. This breaks down to:
2,300 miles of motorway
29,500 miles of ‘A’ roads, and
215,200 miles of minor roads.
(I’m not sure where the other 100 miles went, if anyone from the DoT is reading this perhaps they could clarify this?).
Along all these miles and miles of tarmac. widths vary considerably.
It wasn’t until 1991* that a standard for the paved width, the area of road that vehicles drive on, was set and even then that was for only new roads – they couldn’t really relay every road.
This was set to 3.5m or just under 12 feet,doubled for two lanes.
Of course, some flexibility is allowed on roads; with roads being narrowed or widened particularly where turning circles are needed.
And for motorways, it’s dependant on the number of lanes. A six-lane motorway will be roughly 22m wide or 72ft – 12ft per lane.
For older roads, pre 1993, there wasn’t a standard and they all vary.
A rule of thumb I work to is to model my roads to Roman road – as many British roads were built on these. And Roman roads were around 2.4 m or 7.87 f feet on straight sections and 4.9m / 16ft on turns although some were much wider. Trunk roads, those running between towns, meanwhile were approximately 7 m or 23 ft.
For country lanes, pretty much anything goes with the further outside of towns the narrower and frequently to narrow for cars to pass when in deep countryside.
The Department of Transport has specified that 4.1 metres is the minimum width for a car to pass a car so this is, or close to it, is what I use for country lanes where cars can pass and half this for single track roads.
UK Road Widths In N Scale
These above sizes equate to the following for UK N gauge (1:148) or 2mm to the foot.
| Modern A & minor roads | 24mm / Lane |
| Motorways | 24mm x No. of lanes |
| Older minor roads (based on Roman road widths) | 15mm |
| Older trunk roads (based on Roman road widths) | 46mm |
| Country roads | 26mm |
UK Road Widths In OO Gauge
| Modern A & minor roads | 48mm / Lane |
| Motorways | 48mm x No. of lanes |
| Older minor roads (based on Roman road widths) | 30mm |
| Older trunk roads (based on Roman road widths) | 92mm |
| Country roads | 52mm |
Pavement Widths In N Scale and OO Gauge
Of course, most roads have pavements and these two have defined dimensions. The Department of Transport Manual For Streets, states a specification of 2meters for footways.
This translates to widths of:
| N Scale Pavements | 13mm |
| OO Gauge Pavements | 26mm |
Interestingly, kerbs also have defined dimensions.
So there you have it. Of course, as anyone who has every travelled on a road in Great Britain knows, the sizes change as does the surface so sticking to these dimensions will give you a good start don’t be too worried if you need to vary them slightly on your layout. As long as you’re close to these, your roads will look right compared to the track, buildings and scenery.
References:
Department of Tranport Road statistics, 2019
New Roads and Street Works Act 1991
> A final, personal, note: I spend a huge amount of time testing, photographing, writing and researching techniques for these articles and pay for all the running costs of MRE out of my own pocket. If you found this article useful you can support me by making a donation on my fund-raising page. Thanks and happy modelling, Andy.
Andy is a lifelong modeler, writer, and founder of modelrailwayengineer.com. He has been building model railways, dioramas, and miniatures for over 20 years. His passion for model making and railways began when he was a child, building his first layout at the age of seven.
Andy’s particular passion is making scenery and structures in 4mm scale, which he sells commercially. He is particularly interested in modelling the railways of South West England during the late Victorian/early Edwardian era, although he also enjoys making sci-fi and fantasy figures and dioramas. His website has won several awards, and he is a member of MERG (Model Railway Electronics Group) and the 009 Society.
When not making models, Andy lives in Surrey with his wife and teenage son. Other interests include history, science fiction, photography, and programming. Read more about Andy.