How much should following distance increase in wet weather under the Northern Ireland Highway Code?

In wet weather, stopping distances can be at least double those on a dry road, so your following gap should increase accordingly.

Less tyre grip and reduced visibility mean you need more time to react as well as more distance to stop.

For “How much should following distance increase in wet weather under the Northern Ireland Highway Code?”, the wider Northern Ireland context is this: Northern Ireland winter driving is especially sensitive to changing road-surface temperature, rain, ice, flooding and exposed routes. Official advice is to drive for the conditions actually in front of you, not for the posted speed limit or the fact that a road was treated earlier. TrafficWatchNI and current weather warnings are the right live sources when conditions are deteriorating.

For this exact question — “How much should following distance increase in wet weather under the Northern Ireland Highway Code?” — the practical point is: Use the dry-weather gap only as a starting point and increase it further in heavy rain, spray or poor tyre/road conditions. The answer should be applied to the actual signs, conditions, licence wording or parking rules in force at the time, because temporary restrictions and individual DVA decisions can change the ordinary position.

This Northern Ireland-specific page on “How much should following distance increase in wet weather under the Northern Ireland Highway Code?” was checked against the attached official sources before publication, with nidirect/DVA and the Northern Ireland Highway Code used ahead of generic UK motoring articles. If the rule, road layout or personal licence condition changes, those primary sources are the ones to re-check.