The Different Sizes of Jacks Associated with Degrees and Pitches of a Roof
Through the years, no matter how many times roofing jacks are explained by degrees, many still do not either know the difference, or get it backwards. This includes some roofers. Studying this simple explanation should give you an idea of what degree is associated with what kind of jack.
1. 90 Degree Jacks= This type of roofing jack primarily has the shape of a “J” bracket, with another metal piece crossing from the middle of the letter, to the hook-end of the “J”. The metal piece mentioned comes out level if you hold the jack bracket straight up. Roofers primarily use this type of jack on very steep roofs, ranging for 8/12 to 11/12 pitch.[ a 1/12 pitch means the roof levels up 1 inch per foot, so an 8/12 pitch means the roof vertically measures up and angled at eight inches every 12 inches horizontally). Most 90 degree jacks are used with 2×6 boards, so the metal piece the board lies in is at least 6″ long. These type of jacks have a “hook” that wraps over the top of the 2×6, giving the board a safety feature of not flipping up. These jacks also come with holes on the side or top, or both, so you have the option of nailing the board through the jack hole, giving you another safety feature. Today, jacks come primarily in yellow, but there are a variety of colors out there, ranging from grey to blue. this generally applies to most of the jacks mentioned also. 90 degree jacks also have three- or four slits cut into the base,so you can nail the bracket to the roof itself. this keeps the jack attached to the roof, giving the roofer(s) comfort knowing they are not going to fall off. This is also where the 2×6’s overlay each other if the roofer doesn’t have a board long enough for this part of the roof. Less popular are the 2×4 roofing jacks.
2. 60 Degree Jacks= The same basic design, as well as the same features, except the 60 degree jacks angle the 2×6 farther from the roof, which angles your body farther from the roof, giving you a better level for your feet. These are generally the most popular jack to use and easiest to work with. 60 degree jacks keep you from being snug up against the roof itself and keeps you from being exceptionally close to the roof and is applied on roofs with a pitch of 4/12-8/12.
3. 45 Degree Jacks= Also the same basic design as the 90-and 60-degree jacks, but 45 degree jacks have the metal aligned to where you are standing up straight if applied to a very low pitch roof. Rarely used, these type of jacks actually come primarily in the color of red, and are NOT safe on any pitch higher than a 4/12. More often then the other sizes, 45-degree jacks come in sizes to fit a 2×8″ and 2×10″ board. These size boards, (not jacks), are often associated with slate roofs and are also used as a “bottom catch”, installed on the edge of a roof.
4. Adjustable Roofing Jacks= This type of jack is the only one that adjusts, therefore it doesn’t stay permanent, unlike the first three jacks mentioned. This is also not a one-piece metal like the first three mentioned.There are three movable arms for adjustment. Jacks of this nature are often used to adjust to to pitch of the roof, keeping the roofer from buying excess jacks every time he’s put on a different pitch, either from the same roof or a totally different one. The safety features of this jack is generally not as safe as the fixed angles, because there is always the chance that the screw might break, or the nut might screw itself off. There is always a danger factor when dealing with this type of jack, and the only bonus of owning and installing this type of jack is the different pitches you can set this to, to conform with the level ability of the house=i.e. There are usually five different settings on this jack, so if the house is between a 5/12 and a 6/12 pitch, you can set the difference by adjusting the bracket.
All roofers, as well as roofing companies, are different. some require you to use 90 degree jacks on all roofs, and some not. this is to just explain the numbers associated with the degree of jack.
This is a list ONLY used to explain the degree of each bracket by name, not by what law you are supposed to you these for.
Rules are different in all states, so please look at the laws from each state to find out if the rules of thumb are for what type pitch is necessary for what degree. Laws vary.
Be careful
