A common mistake is to attempt to cut laminate flooring to circumnavigate these door jambs, which often ruins the whole look and feel of the entire job.
You must cut your door jambs/frames and install your laminate flooring under it, rather than attempt to circumvent it with overly complex cuts. This is the only way your 
doorway will appear flush and your laminate will look as though a professional has installed it.
Whatever the outcome of your laminate job, the fact you have attempted to do everything properly will make your job better than most DIYist’s.
In this article, we will look at how this can be done, and what tools should be used to ensure your doorways look amazing in each and every room.
What saw you will need to successfully cut your door jambs
Having had a quick look around the articles online I have seen there are a number of different saws and tools that people recommend for this process. I will however be providing my own recommendations based on my experience.
I personally favor an oscillating tool (Amazon link) for making these door jamb cuts. For those that don’t know this tool I will write an article dedicated to it, but for the time being, understand that one of its many cutting functions allows you to make accurate door jamb cuts.
An alternative to an oscillating tool is a pull saw (Amazon link),which I can see has been recommended by many – a pull saw will take a little more getting used to and is not as beginner-friendly – but it will most likely be the cheaper option.
Choosing Your Blade
Oscillating tools (Amazon link) are made to be used with numerous materials (not just wood), so it is important to use a blade that has been made specifically for wood (assuming this is what your door jambs/frames are made of).
You can use either a rounded blade (my favorite) or a straight blade. This choice will only affect how you make your cut and not the final finish.
How to cut door jambs/frames with an oscillating tool
We will now look at the actual process of cutting the door jamb/frame. I have also added a video below (not mine) that I believe demonstrates the process quite well.
Hopefully, I will get around to doing my own video soon, however, until then this should give you a good idea of what you are trying to achieve and how the finished flooring will look.
The video does not make particular mention of expansion gaps – make sure your laminate under your door jamb has a similar expansion gap as the rest of your floor. This will of course be hidden under your door frame.
Clean Your Work Area
You should always start any DIY project with as clean a space as you can. Make sure all unnecessary items are removed and that there are no offcuts or other pieces that may hinder your movement around the door jamb.
Use An Offcut As Your Measure
When cutting your door jambs it is a good idea to use a piece of the actual flooring you wish to install as your measure for the cut. This will give you the exact height that your cut should be made at.
Attach Your Oscillator Saw Blade
Attach the saw blade that you have decided to use to your oscillator tool. We will be looking to rest the blade on top of the off-cut so as to cut the door frame at the perfect height. Minimizing any potential gaps between the frame and the new flooring.
Place The Blade Flat On Your Off-Cut
Rest your blade on your offcut and get a feel of how the cut should be made. You don’t want to lift the blade of the off-cut during the actual cutting process.
Make Your Cut
Carefully make your cut(s). Concentrate on keeping the blade straight and not lift it off your off-cut.
Remove Any Excess Wood
Once your cut has been made using a chisel, crowbar, or another implement to free the wood and clean it up as necessary.
Video
The video below will give you a good idea of how this cut is made. It doesn’t really get going until 2:20 into the video (I have started it at this time for you) – but I think perfectly illustrates what you should be looking to achieve.
