Coping Vs Miter Crown Molding; Which is better for inside corners? 

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When installing crown molding, you’ll have to turn a corner at some point. The long, straight crown molding pieces are relatively easy to install. However, inside corners are a bit challenging to install as they involve creating tight joints. More importantly, you’ll need to choose between coped and mitered joints. 

The coping Vs Miter crown molding debate has been going on among trim carpenters for years. Many crown molding installers prefer to miter inside corners claiming that it’s faster and provides a cleaner look. On the other hand, some claim that coping is better than mitering as it forms a tighter joint. Moreover, coped joints don’t open up when you’re nailing the trim. 

So, which one is actually better than the other; Coping or mitering? Well, that’s exactly what I’ll be looking at in this post to help you choose the best option for your next crown molding project!  

Coping crown molding

Coping is the traditional way of joining inside corners in crown molding installation projects. It involves cutting one piece of crown molding following the shape of the curved trim. This allows it to fit perfectly against the complex detail of another crown molding piece within an inside corner. For that, it’s considered a mark of craftsmanship and is usually preferred for work with periodic or historic moldings. 

To create a coped joint, one piece of crown molding is cut square and butted into the wall corner. While the mating crown molding piece is cut to match the profile of the 1st piece using a jig saw or coping saw. This allows the end of the mating piece to fit perfectly into the end of the 1st molding piece. 

Benefits of Coped molding joints 

One major drawback of mitered joints is usually realized when you nail the crown molding to the wall. Specifically, the mitered joints tend to open up if one of the 2 crown molding pieces doesn’t remain vertical. For instance, if there is some thick drywall mud at the bottom of the wall, the molding lies back, causing the mitered joint to open at the top. 

On the other hand, coped joints are less affected by imperfect walls. Instead, they open up less compared to mitered joints when the crown molding material shrinks during dry weather. Even better, coped joints handle out-of-square inside corners better than miter joints, which require a 90-degree inside corner for a perfect fit. In addition, your coped cut doesn’t have to be perfect to make your inside corners look perfect as the 2 pieces will fit together without a visible gap. 

These benefits make coped joints ideal for use in various areas such as; 

• Walls that aren’t square

As already mentioned, coped joints accommodate walls that don’t meet at exactly 90 degrees better than mitered joints. Alternatively, adjust your miter cuts by 1 -2 degrees off of 45 degrees to fit out-of-square walls. 

• Humid areas 

Coped joints are recommended when installing wood crown moldings in areas that experience radical seasonal changes in humidity level. This is because large seasonal fluctuations increase the chances of corner joints opening up. Interestingly, these gaps are likely to show when you’ve joined your inside corners with coped cuts. 

• Projects that need a polished look 

If you want to duplicate the original craftsmanship in your traditional home, coping inside corners provides better results than mitered joints. Besides, coping is a more historically accurate joinery method than mitered joints. 

• Inside corners of crown molding 

Since crown moldings are installed higher on the wall, they’re much more visible than other types of trims like baseboards. Therefore, it’s good to use coping for your crown molding inside corners to form perfectly shaped joints as they’ll be more visible to your guests. 

Drawbacks of coping crown molding 

On the downside, coping cannot be used for connecting cuts or outside corners, as it’s only intended for inside corners. More notably, these joints require more skills and patience than mitered joints. On the same note, coping requires a special technique to make precise cuts as it involves using a hand saw, making it more time-consuming. However, once you master the art of coping, your cuts can be as fast as mitering, but that type of speed will take a lot of practice. 

Mitering Crown Molding 

Mitered cuts/ joints in crown molding refer to when 2 pieces of trim are cut at 45 degrees so that they can meet on an outside corner. Mitering can also be used to make cuts for inside corners. However, they’re generally more difficult to cut than coping inside corners, especially if your walls don’t meet at a perfect 90-degree angle. 

In most cases, the inside corners of walls aren’t perfectly square due to the drywall buildup that naturally occurs in these parts during construction. For that reason, many professional carpenters prefer to cope inside corners instead of mitering. However, mitering is generally the faster and easier technique for cutting crown molding corners, making it ideal for beginners. Also, it’s commonly used in other woodworking projects like picture frames where perfect 90-deg angles are needed. Another benefit of mitering crown molding is that it provides a more professional finish since there are no cut edges visible. 

To make a mitered cut, you either need a hand miter box & saw or a power miter saw. Interestingly, the best miter saws for crown molding are equipped with fine-tooth blades, allowing you to quickly cut your corn molding pieces for mitered joints at perfect angles. 

Benefits of Mitered joints 

• Speed 

Most homeowners finish making mitered joints of an entire room at the same time it would take them to learn how to cope crown molding. This makes mitering the fastest technique of cutting joints for inside corners when installing crown molding, baseboards, and other trims. 

• Ideal for beginners 

Making mitered cuts is a relatively simple task even for beginners provided you’ve got a crown molding miter saw. You only need to lock it to the 45 deg angle, press your crown molding against the fence, and saw down to cut a precise open angle. In comparison, coping is a bit difficult for beginners and requires a lot of practice & skills. 

• Suitable for non-wood crown molding 

Non-wood trims like MDF and polyurethane molding aren’t susceptible to shrinkage. Unlike wood, polyurethane and MDF don’t expand or contract under normal conditions. Therefore, there is no need to cope the joints since they will not shrink to leave visible joints after installation. 

Drawbacks of mitering crown molding inside corners 

As you’ve seen, mitering trim has its benefits such as increasing the speed of your project. However, it has its set of drawbacks too. For instance, you cannot use a miter saw to make custom angles as they can only cut 45 and 90-degree angles. 

Another drawback of mitering inside corners is that the joints tend to open up, especially if your wall corners don’t meet at a perfect 90-degree angle. So, if you’re planning to make miter cuts for your crown molding inside corners, make sure you adjust the angle to reduce any visible gap! 

What is the main difference between a coped joint and a miter cut? 

In this context, a miter cut refers to cutting two pieces of crown molding at an angle of 45 degrees where they meet at an inside corner of a ceiling or wall. Both cuts are made at a 45-degree angle to allow a seamless transition when installed. 

On the other hand, a coped joint is when one piece of crown molding is installed against the wall without any angled cuts at the inside part of the inside corner. The next piece is then cut with a coping saw to slide over the installed piece to form a tight joint. 

Important factors to consider when comparing coping Vs Miter crown molding 

When deciding between coping and mitering for your inside corners, there are various factors you need to consider. According to professional carpenters, these factors might make one technique preferable to the other. 

• Most inside corners are not a perfect square 

Very few rooms have corners that meet at a perfect 90-degree angle. This makes it a bit difficult to perfectly fit 2 pieces of angled trim at inside corners. If that’s the case with the project you’re working on, consider using coped corners. Coping ensures that both pieces of trim overlap slightly to form a tight joint, leaving no gaps. Alternatively, you can just miter the inside corners and hide the gaps with paint and caulk. 

• Crown molding material 

The type of crown molding is another factor that will play an important role in determining the best technique to use for cutting inside corners. If the trim is made from fragile material, avoid cutting it with a tool that might cause it to fall apart or get chipped. For instance, if you’re installing white lacquered molding, a sharp, high-speed miter saw is preferred instead of coping. Similarly, if the profile of the trim has near-negative angles that are difficult to cope, miter the inside corners instead. 

• Humidity Level 

Wood crown moldings expand and shrink when installed in a humid climate, depending on the weather. For that reason, most installers prefer coping inside corners when installing trim in areas with dry winters and humid summers. That is because coping creates tight joints that will not swell or shrink when exposed to various weather conditions. 

What is better; Coping or Mitering crown molding? 

While many carpenters prefer coped joints for inside corners, the miter is generally the faster and easier method for beginners. But as you’ve seen above, both methods have their share of benefits and drawbacks. For instance, mitered joints can leave unwanted gaps between the 2 pieces of crown molding. This makes coping the better technique for inside corners, especially when you’re installing trim in out-of-square walls. 

So, if you have a lot of crown molding to install, I’d recommend you take the time to learn how to cope with trim, even if you’re a beginner. One thing you need to note though is that you can only use the coping method for inside corners, but not for outside corners!