Greetings Pals and Gals.
As the topic Says road widths and sizes. I need the measurements, that bieng for anything that would be on a road/(back)street/highway and or freeway. Im in the prosses of doing plans and so forth, and thus I need those legths. Im a little bit of a perfectionist and bieng my 1st layout im REALLY trying not to give into my perfection obsession but the measurements of things is something I really cant look past. 
Thanks!
T
A huge range of factors come into play here, including the era. Was the road designed/ built in the days of horse and cart/ trams/ cars? Was the road an important or prestigous road - those are often wider?
For current day:
Residential streets huge range - from 5m wide for two moving lanes up. Allow about 2.1-2.5m for kerb side parking.
City streets - 3.5m wide lanes are typical.
Freeways - typically 3.75m per lane.
My advice is to have a look at your prototype location in real life or on Google Earth
good idea
Measure the real roads you want to model. Convert to inches. Devide by 87 for HO (or 160 for N) This will give you the scale width for your roads. Now when you transfer these dimensions to your layout, you will see that they look WAY too wide. A lot of people just do what looks good.
2.25"-2.5" looks pretty good for a 2 lane HO scale road.
Here is some info that might help!
N scale 1 inch = 13.3 ft.
HO scale 1 inch = 7.2 ft.
S scale 1 inch = 5.3 ft.
O scale 1 inch = 4 ft.
Highway lane - 12-14 feet (U.S. highway standards require a minimum 12-foot-wide lane for highway speeds). In HO that’s about 1.66-1.93 inches per lane or about 3.31-3.86 inches for a two-lane highway.
City street - normally 10-12 feet (remember a modern truck can be 8.5 feet wide plus mirrors and some modern fire equipment and transit buses are wider). In HO that’s 1.34-1.66 inches per lane or about 2.76-3.31 inches for an HO version. Main street lanes will normally be 12 feet wide, side streets may be only 10 feet wide, not counting any provision for parking.
Residential streets - in my neighborhood, they are 27 feet curb-to-curb. This is fairly common to reduce speeding as it’s too narrow for opposing traffic lanes if vehicles are parked on both sides. Figure two eight-foot-wide parking lanes and an 11-foot-wide center traffic lane. In HO, such a street would be 3.72 inches wide.
Parallel Parking Lane - 8 feet wide. 1.1 inches in HO.
Nose-in Parking Lane - Depends on angle, but figure 16 feet, or about 2.2 inches in HO.
Shoulder - anywhere from none to eight feet. Real divided highways will usually have an 8-foot shoulder on the outside, a 4-foot shoulder on the inside and a 60-foot median. That would be more than 18 inches wide in HO.
5 to 5.5 inches will give you a good city street with two lanes of traffic and parallel parking on both sides.
Good rule of thumb for a road is to take two medium-to-heavy HO trucks, put them next to each other so their rearview mirrors don’t touch, and measure the distance between the outside mirrors. With the Athearn Ford C, that works out to be 2.75 inches, which is just under 10 scale feet per lane. Please note this won’t work with some of the Boley trucks as a few of the commercial bodies are oversized for HO scale. You’re also going to need much wider lanes if you’re still using Hot Wheels or other non-scale vehicles. Even the Matchbox International CXT everyone thinks is