Steep Slope Roofing

The slope of a roof is often referred to as the pitch. The slope, or pitch, of the roof is deter­mined by the ver­ti­cal rise in inches for every hor­i­zon­tal twelve inch (12″) length (called the “run”). A roof with x rise/12 run slope means that for every 12 inches hor­i­zon­tally (run), it rises x inches.

Gen­er­ally, roof­ing types and roof­ing prod­ucts are typ­i­cally divided up into two pri­mary cat­e­gories, steep slope roof­ing and low slope roof­ing.  Some­times steep slope roof­ing is also referred to as “res­i­den­tial roof­ing” due to the fact that most sin­gle fam­ily homes in the U.S. are con­structed with some sort of pitch or slope to the roof.  Just as steep slope roof­ing is often referred to as res­i­den­tial roof­ing, the term low slope roof­ing is often­times syn­ony­mous with “com­mer­cial roof­ing”.  Again, this is due to the fact that, pre­dom­i­nantly, com­mer­cial build­ings have “flat” roof designs.

If we were to clas­sify roof­ing slopes more specif­i­cally, the list below con­tains the com­mon roof slopes and the terms which clas­sify them.  How­ever, in gen­eral terms, low slope roofs (com­mer­cial roofs) are those below 2/12 or 3/12 while steep slope roof­ing would con­sists of roof pitches above either 2/12 or 3/12 and higher.

 

      Flat Roof: 2:12

      Low Slope: 2:12–4:12

      Con­ven­tional Slope Roof: 4:12–9:12

      Higher Slopes:  9:12 — 20:12

      Steep Slope: 21:12 and higher

 
Roof slope is a very impor­tant aspect and it is con­sid­ered the pri­mary fac­tor in roof design. The slope of a roof has an effect on the inte­rior vol­ume of a build­ing, the drainage, the style, and the mate­r­ial used for cov­er­ing. For exam­ple, if you notice water col­lect­ing on the roof the prob­lem is prob­a­bly related to the slope. The style is affected too because the fram­ing of the roof changes the slope.  Steep slope roof­ing prod­ucts are gen­er­ally more visu­ally appeal­ing because they are crit­i­cal aes­thetic com­po­nents for res­i­den­tial con­struc­tion where the roof can con­sist of 40% of the exte­rior visual appear­ance of a home.  Steep slope roof­ing also gen­er­ally lasts longer than low slope roof­ing because the sys­tems shed water much more effi­ciently and gen­er­ally are sub­ject to less direct U/V activity.

Lawrence Media Group

Google+