Difference between dual carriageway and 2 lane single carriageway?

Question

What is the difference between a dual carriageway and a single carriageway with 2 lanes in each direction?
I know the speed limit is 70 on dual carriageways but 60 on singles and want to make sure I know the speed limit of a road I drive on which I think is a dual but may be 2 lanes single.

Answer 1

The difference is what's between the two directions of traffic flow.

If you can't drive into oncoming traffic without crashing through a barrier, driving over a kerb, or any other physical barrier, it's a dual-carriageway. (There can be gaps in the barrier at junctions - that's the only exception). It's also a dual-carriageway if the two carriageways are two separate bits of tarmac, with (say) grass in between (that counts as a physical barrier).

If there are just intermittent islands or bollards in the middle, then it's physically possible to drive into oncoming traffic, so that's a single-carriageway.

Incidentally, I've been told (and I haven't checked, so it could be wrong), that if a dual-carriageway has only one lane in each direction, then the speed limit is only 60 for cars. In other words, although it's a dual-carriageway, it's a single-carriageway as far as speed limits are concerned.

Answer 2

Dual Carriageways

Answer 3

Single Carriageway

Answer 4

There is usually a physical division between the lanes of opposite direction on a dual carriageway,

Answer 5

Simple as it gets a single carriageway has one lane each direction. ( SINGLE)
a duel carriageway has two lanes each direction( DUEL)
The national speed limit does not change if it is duel its 70 if single its 60.
A white line is all that's needed to separate a lane, on any road with traffic moving in any direction ,the only exception is HG V's and coaches, these have to slow down to 40 on duel carriageways without a crash barrier fitted.

Answer 6

if the road you are on has a solid central reservation (seperating you and the traffic travelling in opposite direction) like a metal fence etc then it is a dual carriageway, if it has just trees or bushes then it is a two lane single carriageway.
thats the easiest way to tell.

Answer 7

Almost correct.

A dual carriageway is defined as any road with a PERMANENT division between the two flows of traffic e.g. barriers, Armco, walls, trees, bushes, grass, buildings, water, etc.

If the divide is only a painted line (such as some sections of the A444) or cones fixed into the cats-eye slots, it is only regarded as a temporary division and hence, a single carriageway.

Answer 8

a dual carriageway has a central barrier and a two lane single carriageway does not