A common question that I get form our customers is why are steep roofs more expensive to install? There are a lot of factors that go into answering this question and the goal today is to bring understanding to why! Before we answer this question let’s take some time to explain roof pitches and the benefits/negative aspects to each.
First, it is important to know that the slope of a roof is measured by the term pitch. Let’s use 7/12 pitch as an example. In this example 7 represents the roof’s vertical rise and 12 shows the horizontal run of the roof. So, for every seven feet of vertical rise there is 12 feet of horizontal run. Pitch is the universal unit of measurement for all things roofing! Most roofers will consider a “steep” shingle roof to be any roof with a pitch of 7/12 or greater. Now that we have this understanding, let’s talk about the pluses and minuses of roofs with different pitches!
Steep Slope Shingle Roofs
● The benefits of a steep shingle roof are that it will last longer in comparison to a low slope! Why is this the case? An asphalt shingle roof system is a water shedding system and not a water proofing one. So, with a steep roof the water will shed off of the roof quicker. This will cause less wear and tear on the roof and, with all other factors
consistent, will last longer than a low slope shingle roof.
● The negative aspects of a steep shingle roof are related to the install. A steep roof will take longer to install than one who has a lesser pitch. A steep roof is more difficult to walk on. Installers must be careful during the install process and take proper measures to prevent from being injured during the install. For roofs that are 12/12 pitch or greater most architectural shingles require a different install procedure. With this steep of a pitch, the nailing zone becomes much smaller. The reason the nailing zone becomes smaller is to prevent shingles from delaminating.
The nailing zone becomes smaller because the common bond area must be hit in order to prevent the singles from delaminating. An architectural shingle is a laminated shingle. This means that there are two parts to the shingle. The area where the two parts of an architectural shingle intersect is called the common bond area. The common bond is the area that the nails must go into in order to prevent delamination.With these circumstances a steep shingle roof becomes more expensive to install than a low slope shingle roof!
Low Slope Shingle Roofs
● The benefits of a low slope shingle roof are that it will not take as long to install. Because of the “walkability” of the roof, installers are able to move quicker. Due to the speed of install that can be accomplished a low slope shingle roof will be less expensive to install!
● The negative aspect of a low slope shingle roof is that they are more prone to issues. Water will take longer to shed off of the roof. This will increase the amount of wear and tear on the shingles and decrease the functional life of them. Any install imperfections can be magnified with a low slope because of how slowly the water moves off of the roof
With this information my hope is you will have a better understanding of why a steep shingle roof is going to be more expensive to install. Even though your steep roof is going to be more expensive, it will be a better functioning roof as well as a longer lasting one!