If you're looking for "shingle roofs – how to" information, you've come to the right place. The trend towards thicker shingles makes the job of cutting them somewhat more difficult. Here's three tools that will do the job …
Shingle Roofs: How to Cut the Shingles – Tool # 1 Utility Knife
Go with a model that allows you to change blades fast without tools. Also, get one with a fixed blade, as retractable blade mechanisms get gummed up with roofing tar. And you want one that fits naturally in your hand, while introducing the blade to the work at an efficient angle. The best utility knife I've found for roofing is a Stanley Model 10-399.
Straight blades cut well on the back of the shingles and hook blades cut well on the front. So you really should have two knives in your tool belt. Keep one ready to go with a straight blade and one ready to go with a hook blade. That saves a lot of time switching back and forth between blades.
Also keep some of both blades in each knife. That way if you misplace one of your knives (which is easy to do) you will be able to get by with one knife.
Shingle Roofs: How to Cut the Shingles – Tool # 2 Tin Snips
Tin snips work surprisingly well for cutting shingle. They are quicker and easier to use than a knife when cutting around pipes and vents. They also work great for cutting shingle valleys.
The only problem is … the gritty shingles are hard on the cutting edges. As such, I can not bring myself to you use brand-new snips on shingle. But when they become too dull for metal, I replace them and recycle the old ones for shingles.
Although many "dinners" use dedicated snips for right and left cuts. I've found that Wiss M3R Straight Cut (Yellow Handle) Tin Snips work fine for most of my metal work … and for shingles.
Shingle Roofs: How to Cut the Shingles – Tool # 3 Shear
This is a tool you do not use all the time, but makes short work out of cutting shingle. It looks like a guillotine-type paper cutter, except it's heavy duty. It can be used easily cut any shingle to just about any angle.
But it really shines on straight cuts. Say you're fitting shingle along a side wall … The shingle shear easily cuts them square and to the exact length you need.
I also use it to salvage shingle scraps at valleys and hips which have the square cut on the wrong end. The shear quickly squares up the proper end for you, putting a "factory finish" on it. It's much faster than a knife and does a better job.
There are two or three models on the market, but my preference is the "Shingle Shear" made by Howard Tools.