Slate Roofing 
All Colorado Exteriors, Inc. Is a fully Licensed  and Insured Roofing Company. We provide flat roofing and will roof house. ​We offer roof  certifications for new home owners. We are here to provide your the Home Owner with honest, truthful , budget constrained sevice that you would expect from the Best roofing contractor we can be. BACK TO ROOFING
All Colorado Exteriors, Inc. honorably serves the follow cities:

​​Slate tiles​ in: Arvada | Golden | Wheat ridge | Highlands Ranch | Commerc City | Centennial | Littleton | Evergreen | Vail |
​ Parker |

Aurora | Brighton | Boulder | Castle Rock | Ken Caryl | Green Valley Ranch | DTC | Morrison | Park County | Greeley | Silverthorne |

Bailey | Aspen | Broomfield | Lafayette | Kiowa | Elizabeth ​​​​
The intrinsic beauty of slate will enhance schools, churches, universities, homes, commercial and government buildings.
Some of slate’s greatest advantages include:
Slate is natural stone -- it is more durable than any man-made material
It is fireproof -- completely non-combustible
It is waterproof because of its high density. It will not absorb water.
The investment in slate is permanent and therefore enhances building value
Lowers net energy costs because of its insulating capability and reflectiveness (due to Vermont slate's high mica content)
Requires little or no maintenance
Resists climatic/seasonal change
Impervious to fungus and mold
The natural color and texture of slate creates a unique and beautiful roof.
It is likely to enhance the appearance of any home or building. Greenstone slate is available in a variety of . . .
Surface textures
Roof textures

Slate grading is based on thickness . . .

Regardless of the grade, all of Greenstone's roofing slate has a life expectancy of at least 100 years. Slate is "graded" according to the uniformity in thickness that each piece exhibits. As with any natural product, the more particular the physical specification, the more demanding the production requirements. Therefore, a slate's grade has great bearing on the availability and overall cost of the material. Here is a list and description of the four slate grades.
Standard Grade "Selects": These premium slates are a very uniform 1/4" in thickness with little texture. Standard Grade roofing slate weighs from 680 to 780 lbs. per square.
Rough Texture Grade: Since natural slate is hand split from blocks of stone, some pieces may be thicker than 1/4" or have natural characteristics that produce uneven surfaces. These slates are recognized as Rough Texture Grade. Rough Texture Grade is not to be confused with imperfections in the stone that would jeopardize the slates structural integrity and waterproofing capabilities. Each slate is free of weakening imperfections, but exhibits a more enhanced grain and variation in thickness. Rough texture grade slate is manufactured at a thickness between 1/4" and 3/8" and weighs between 800 and 1000 lbs. per square.
Architectural Grade: Slates designated as Architectural Grade are the same as Rough Texture Grade except that the slates are from 3/8" - 1/2" thick. Architectural Grade slate weighs from 1200 to 1600 lbs. per square.
Heavy Grade: Slates designated as Heavy Grade are the same as Rough Texture Grade except that the slates are 1/2" - 3/4" thick. Heavy Grade slate weighs from 1800 to 2200 lbs. per square.
Estate Grade: Slates designated as Estate Grade are the same as Rough Texture except that the slates are at least 3/4" thick. Estate Grade slate weighs from 2500-3000 lbs. per square.
About variable slate widths. . .
In a Random Width roof, the widths of the slate vary. An excellent explanation of Random Width natural Vermont roofing slates in the following quote from The Slate Book by Brian Stearns, Alan Stearns and John Meyer:
“A variety of widths will generally be provided by the quarry. The largest percentage of widths shipped will be approximately 2/3 the length of the slate being used; the smallest percentage will be of the largest widths. However, when specifying Random Width this will vary and percentages cannot be specifically ordered. The use of Random Width slate will generally reduce the material cost of the roof. In appearance, the alternating vertical joints between shingles on a Random Width roof will not always line up with the vertical joints from the courses below. If you want to achieve a symmetrical appearance, you will want to avoid Random Widths. In some cases, the use of Random Widths will make an otherwise standard appearance look more textured or cobbled. Random Widths slate can be used with most of the roof types and with other variables, but creating patterns in a Random Width roof is not common.”
Thanks to slate roofing site for info​​​