That's probably because you've never lived on a street designed as a local residential area that has been turned into a rat run. Unfortunately, anyone who has would be in no doubt about that being an overall worse outcome. It undermines the structure of most official traffic planning, sometimes with horrifying results for safety, along with a variety of other undesirable side effects.

Ultimately, all roads are not equal. They are often designed for different purposes, and when they are repurposed for things they were not intended for, very bad things can and do happen. This is a real problem with modern SatNav systems directing large numbers of vehicles along unsuitable routes because they're trying to shave 10s off a journey time, and I imagine laws will be passed regulating such systems before too long (this being easier and more practical than designating all the roads in question as access only and then actually enforcing that law).

Why is it okay to push even more of these costs on people around the main route, don't you think that people in all areas should take on their share of these costs.

Also struggling to see how a guardrail could be burdensome.

I think you might be assuming the aim is to maximize traffic flow, or similar. That's not necessarily the aim of a European city's traffic planners -- they may prioritize pedestrian or cyclist safety, child safety or play space, reducing noise, improving bus/tram speeds, or maintaining a historic appearance. This might be for a single road, a small area, or a whole district.

Several of these can reduce overall traffic. If parents don't think it's safe for their children to walk to school, they might drive them instead -- increasing traffic at the worst time for other children. Similarly for private vehicles obstructing buses and trams.

Heaven forbid that people get where they're going in less time and with greater safety.

The larger roads, obviously, are designed for higher traffic speeds and volumes. Features you might see (depending on how large the road is) include more and wider lanes, restrictions on stopping, fewer curves, better visibility, fewer junctions, pedestrians directed to footbridges or dedicated crossings, better lighting, no buildings opening directly onto the roads, and suchlike.

For example, see [1] blue roads being slower/lower capacity, and orange and red being larger, higher speed roads.

  Also struggling to see how a guardrail could
  be burdensome.

(IMHO if people don't want a road used as a through road, they should get the road blocked at one end - rather than expecting a legislative solution - and if they don't want the inconvenience of going around, perhaps they should consider that other road users don't either)

[1] http://www.stgeorgenp.org.uk/wp-content/uploads/2015/01/Prop... [2] https://goo.gl/ETDx3h

I would think having gaps in the barrier, say every five or ten meters would be sufficient?

I like your humble opinion :) that seems like quite a fair solution all around.

* pet owners (even cats aside, some dogs often escape the house),

* younger kids who don't have the same safety awareness and often just run off,

* older kids who parents would normally trust to cycle to their friends house.

Barriers also create parking problems:

* how do barriers work when you have houses with driveways?

* and if don't have driveways then how do you park on the street now that you've made it harder to get on and off the pavement?

Barriers legitimise speeding down the road which puts cars parks on the street at greater risk of getting damaged (I've seen this happen far to often along rat runs).

Plus there is also the noise polution problem of living next to a rat run. In fact it's worse than along main roads because you end up with car engines revving as they maneuver around parked cars at speed rather than the constant steady drone of cars going past. You have no idea how annoying this is during the summer when you want windows open and the cars are louder than your own bloody TV!

People who move into a main road do so knowingly and are willing to live with the drawbacks it brings. Though often those kind of houses have longer front gardens so the house is set further back from the road and/or hedges or other noise cancelling greenery (sometimes - not always though). But if you move onto a quieter street you do so because you want a safer and quieter environment. Which is why residents protest against their streets being turned into through-roads

As to guardrails, they create a significant barrier, not only for, say a pedestrian being slammed into them by a car, but also from a neighbourhood community point of view. The problem is not the people walking and cycling, but the people using it as a convenient cut through.

If the city wants to use a road for arterial traffic, they should upgrade it to handle the task.

Filtered streets (placing bollards at one end) are a key tool in rebalancing anti-social behaviour primarily caused by congestion on major routes. It is not changing the function of the road, but enforcing the original designed purpose of the road to be an end destination and not a convenient through route.

It is also significant tax saving. Residential roads are not designed for significant volumes of traffic and can suffer significant damage if they become overused.