All Sign Designs shall be shown in the plans. All signs that do not have a standard panel design in the MUTCD Standard Highway Signs (SHS) manual shall have a panel layout with an NCDOT sign panel report shown in the plans. The sign designs and panel reports shall be prepared using the latest version of GuideSign software or Openroads Designer and the latest
NCDOT Panel Reports. For signs with a standard panel design in the MUTCD SHS, the size, color (if applicable), and mounting type shall be shown on the plans. Panel designs that are not provided in the MUTCD SHS, shall be designed by the engineer and approved by NCDOT.
Type A, B, D and Overlay sign designs shall contain the sign number, sign size, type of sign, quantity, total area of the sign, type of border, background color, copy color, symbol size and location, material thickness, spacing factors, number of Z-bars, the applicable notes for fabricating the sign and the letter spacings. Letter spacings shall be measured to the start of the next letter. Provide a detail to assist with installation.
Sign Colors
If not specifically addressed in the MUTCD SHS, signs shall be designed according to the following criteria. If a SHS design exists, that standard shall take precedent over the following criteria.
The MUTCD specifies sign color based on sign purpose in Section 2A. Unless identified in the MUTCD SHS, the color of each sign shall be specified on Sign Design sheets of the plan set.
RED - stop, yield, or a prohibition. Examples include WRONG WAY, DO NOT ENTER, and NO PARKING.
GREEN - indicates movements permitted, or directional guidance. Examples include directional signs or permissive parking regulations.
YELLOW - general warning such as MERGE, or LANE ENDS.
BLUE - general services, logos leading to motorist services such as lodging, food, or gas, and hospitals with 24 hour emergency care.
BLACK on White - regulatory signs. Examples include ONE WAY, KEEP RIGHT, and SPEED LIMIT.
ORANGE - construction and maintenance work zones. They warn drivers of unusual conditions and of people and machines working on or near the roadway.
BROWN - recreational and cultural facilities signs.
Fluorescent Yellow-Green - warning signs, such as SCHOOL CROSSING, PEDESTRIAN, and BICYCLE.
Fluorescent Yellow - warning signs, such as RAIL CROSSING.
Additional Resources
MUTCD Table 2A-5 (Link)
MUTCD Standard Highway Signs (SHS) (Link)
Sign Sizes
Sign heights and widths shall be in increments of 6". Follow the MUTCD SHS and NCDOT signing typicals as close as possible and increase the line spacing or outer edge spacing to maintain a 6" increment. See MUTCD Section 2E.15 for guidance on interline and edge spacing for guide signs on expressways and freeways.
Unless otherwise approved by the SDU:
- Interline spacing of upper-case letters should be approximately three-fourths the average of upper-case letter heights in adjacent lines of letters.
- The spacing to the top and bottom borders should be equal to or greater than the letter height of the largest adjacent line of letters.
- The lateral spacing to the vertical borders should be equal to or greater than the height of the largest letter.
Additional Resources – Freeway and Expressway Guide Signing
MUTCD Section 2E.15 Interline and Edge Spacing. (Link)
Link to MUTCD SHS Design Guidelines
Letter Series
Letter series for the standard alphabet are B, C, D, E, Emod and F. Lettering for names of places, streets, and highways on guide signs shall be mixed case (upper and lower) and use the D or Emod series depending on the letter height. Letter heights up to and including 8" shall use the D series. Letter heights at 10.67" and above shall use the Emod series.
All other lettering on guide signs shall be all capital letters and use the E series. Legends on regulatory and warnings signs shall be all uppercase letters and can utilize any letter series except Emod.
Interline spacing for messages using mixed case letters with underhanging letters (g, j, p, q, and y) shall be increased according to the following chart:
| Letter | 6" | 8" | 10.67" | 13.33" | 16" | 20" |
| g | 3.00 | 4.00 | 4.00 | 5.00 | 6.00 | 7.50 |
| j | 2.90 | 3.86 | 3.86 | 4.83 | 5.80 | 7.25 |
| p | 2.40 | 3.20 | 3.20 | 4.00 | 4.80 | 6.00 |
| q | 2.40 | 3.20 | 3.20 | 4.00 | 4.80 | 6.00 |
| y | 2.20 | 2.93 | 2.93 | 3.67 | 4.40 | 5.51 |
For messages with hyphens, the spaces on either side shall be half the height of the uppercase letters.
Example: Winston - Salem 16"/12" Emod letters – spaces before and after the hyphen and the hyphen will be 8" each.
Additional Resources
MUTCD Section 2D.05 Lettering Style (Link)
MUTCD Section 2E.14 Size and Style of Letters and Signs (Link)
Letter Height
Letter heights shall be large enough to provide necessary legibility distance, with a specific ratio of 1 inch of letter height for every 30 feet of legibility distance. For a general letter height discussion, refer to MUTCD Section 2A.13. For letter heights on guide signs on conventional roads, refer to MUTCD Section 2D.06. For letter heights on guide signs on
expressways, refer to MUTCD Tables 2E-2 and Table 2E-3. For letter heights on guide signs on
freeways, refer to MUTCD Tables 2E-4 and Table 2E-5.
Additional Resources - Conventional Road Guide Signing
MUTCD Section 2D.06 Size of Lettering (Link)
Additional Resources – Freeway and Expressway Guide Signing
MUTCD Section 2E.14 Size and Style of Letters and Signs (Link)
MUTCD Table 2E-2 Minimum Letter Heights and Numeral Sizes for Expressway Guide Signs According to Interchange Classification (Link)
MUTCD Table 2E-3 Minimum Letter Heights and Numeral Sizes for Expressway Guide Signs According to Type (Link)
MUTCD Table 2E-4 Minimum Letter Heights and Numeral Sizes for Freeway Guide Signs According to Interchange Classification (Link)
MUTCD Table 2E-5 Minimum Letter Heights and Numeral Sizes for Freeway Guide Signs According to Type (Link)
Corner Radius and Border Dimensions
Corner radii are generally determined by the shortest dimension of a sign size. Refer to design guidelines in SHS (Link).
Sign border thickness and inset are determined by the letter height of the major copy. Light backgrounds (white, orange and yellow) require the border to be inset.
Shield Sizes
Shield height is determined by letter size on guide signs and type of road on route marker assemblies. Width is determined by route number (1-, 2- or 3-digit, with the exception of NC). NC shields are diamond shaped. The following table shows the shield size and the cardinal direction text size with the corresponding sign location and major copy letter heights.
| Location | Major Copy Letter Height | US and Interstate | | NC | Cardinal Direction |
| | | 1- and 2-Digit | 3-Digit | All | |
| Ground Mounted | Milemarker | 12"x12" | 15"x12" | 12"x12" | 6.6"/6"B |
| Ground Mounted | 8" | 24" X 24" | 30" X 24" | 24" X 24" | 8"/6"E |
| Ground Mounted | 10.67" or 13.33" | 24" X 24" | 30" X 24" | 24" X 24" | 10"/8"E |
| Ground Mounted | 16" | 36" X 36" | 45" X 36" | 36" X 36" | 15"/12" E |
| Ground Mounted | 20" | 48" X 48" | 60" X 48" | 48" X 48" | 18"/15" E |
Overhead (40mph or less) | 10.67" or 13.33" | 24" X 24" | 30" X 24" | 36" X 36" | 10"/8"E |
Overhead (45mph or more) | 13.33" | 36" X 36" | 45" X 36" | 36" X 36" | 12"/10"E |
| Overhead | 16" | 36" X 36" | 45" X 36" | 36" X 36" | 15"/12" E |
| Overhead | 20" | 48" X 48" | 60" X 48" | 48" X 48" | 18"/15" E |
The following table shows the shield size, auxiliary plaque size and arrow size for Type F Route Marker Assemblies.
| Location | US and Interstate | | NC | Auxiliary Plaques | Arrows/JCT |
| | 1- and 2-Digit | 3-Digit | All | | |
-Y- Line
| 24" X 24" | 30" X 24" | 24" X 24" | 24" X 12" | 21" X 15" |
Freeway or Expressway
| 36" X 36" | 45" X 36" | 36" X 36" | 36" X 18" | 30" X 21" |
Retroreflective Sign Sheeting
In North Carolina all non-black elements of roadway signs are required to be retroreflective. NCDOT has three grades of retroreflective sheeting for various intents and purposes. The signing plans shall state the required NCDOT Grade of Retroreflective Sheeting for each sign.
For signs with panel designs, the sheeting grade for the legend, arrows, shields, background and thickness shall be stated in the notes section of that panel design. See Table 901-1 and 901-2
(Link) for appropriate aluminum thickness. For Type E and F signs the sheeting grade shall be stated in the General Notes on the title sheet. For Type E signs requiring Yellow-Green fluorescent sheeting, the note shall appear on the Regulatory and Warning Sign Design sheets.
Additional Resource
TEPPL Policy S-68: Standard Practice for Retroreflective Sign Sheeting (Link)
Sign Design Order
Signs with custom panel designs should be shown four to a sheet, in numerical/alphabetical order. On Type E Sign, Type F Sign and Milemarker sheets - the numbers should increase top to bottom and then from left to right. Milemarker sheets should be ordered from lowest mile posting to highest, from top to bottom and then from left to right.
Additional Resources
NCDOT GuideSign Updates (Link)
MUTCD Standard Highway Signs (SHS) (Link)
