Pitch is thus the ratio of the rise in inches to a 12 inch run and is often expressed using a semicolon for example 6 12.
													
																	Standard roof pitch angle uk. 
								
	
		
	
																	Pitches of less than 2 12 are considered flat roofs even though they may be very slightly angled. 
																	As aforementioned there is no standard pitch of a roof. 
																	In the usa the range of standard pitches is anywhere between 4 12 and 9 12. 
																	This means if a roof rises 4 in the length of 12 your roof pitch would be 4 12 or 18 43 degrees. 
															
													
								
	
		
	
																	This measurement is best done on a bare roof because curled up roofing shingles will impair your measurement. 
																	These are utilized in residential applications. 
																	The most commonly used roof pitches fall in a range between 4 12 and 9 12. 
																	Roof pitch varies depending on culture climate style and available materials. 
															
													
								
	
		
	
																	The picture below shows the pitch of a 7 12 roof slope meaning that for 12 of horizontal measurement roof run the vertical measurement roof rise is 7. 
																	Pitches lower than 4 12 have a slight angle and they are defined as low slope roofs. 
																	Roof pitch or slope is a measure of vertical rise to horizontal run expressed in inches per foot. 
																	Outside of the u s a degree angle is typically used. 
															
													
								
	
		
	
																	Thatch is used occasionally on new dwellings and demands a roof pitch of at least 45 and more likely 50 to allow the rain to flow off quickly and prevent ingress. 
																	For instance a 7 12 roof pitch means that the roof rises 7 inches for every 12 horizontal inches. 
																	So if your roof rises 4 inches for every 12 inches of horizontal length then the pitch of your roof is expressed as 4 12. 
																	A ratio is the most common way of expressing roof pitch or roof slope but degrees are also possible. 
															
													
								
	
		
	
																	In the united states a run of 12 inches 1 foot is used and pitch is measured as the rise of the roof over 12 inches. 
																	A a roof with a 6 rise for every 12 run has a 6 per foot or 6 in 12 pitch. 
																	It is often compared to slope but is not exactly the same. 
																	In the uk the typical house has a pitch between 40 50 although 45 should be avoided. 
															
													
								
	
		
	
																	On blue prints architects engineers usually display the pitch of a roof in the format shown on the image where number 4 represents a rise and number 12 represents a length. 
																	Express roof pitch as the ratio of the amount of the vertical rise of a roof or rise over the corresponding horizontal distance or run you write the pitch assuming a run of 12 inches thus the ratio would describe how much a roof rises for each foot of the run. 
																	The way pitch also known as roof slope is measured is rise over run. 
																	Roof pitches exceeding the level of 9 12 or approximately 37 degrees are termed steep slope roofs. 
															
													
								
	
		
	
																	Some of the most common roof pitch types are conventional slope type roofs designed with pitch ranging from 4 12 to 9 12.