[Talk-GB] Implicit speed limits: What to tag in built-up areas?

[Tobias Zwick]

Does the "there are no repeater signs" rule only apply for the default
30 mph limit (and the 20 mph zones)? Or in other words, if there is an
explicit different limit posted, let's say 40 mph, does it have to be
repeated at each intersection and feed roads?

Tobias

On 01/05/2018 16:35, Philip Barnes wrote:
> 
> 
> On 1 May 2018 10:41:28 BST, Tobias Zwick <osm at westnordost.de> wrote:
> 
>> This is where I need your help. How should the dialog be changed (in
>> GB)
>> to not create any misunderstandings here?
>>
> Difficult without having seen the speed limit signs as you have entered the zone. 
> 
> My usual approach is to survey the change points, split the ways at those points. Often the limit change is painted on the road so can be seen on imagery. 
> 
> 20 limits are likely to exist in the centre and close to schools, so those areas need survey to check. If in doubt leave the limit unmapped.
> 
> The radial roads are the usual start point for mapping speed limits, these are where the transitions usually occur and are where the 40 zones are found. In cities it is rare to find a direct 30 to NSL change.
> 
> If a road is has no speed limit sign it will inherit the speed limit from its feed road, which if that has been mapped makes it easy.
> 
> In the case of short limits where a road passes through a small village you need to be able to split the way at the zone transitions otherwise you will end up tagging the entire way.
> 
> Phil (trigpoint) 
>