Curse of most ready to wear jackets, and all too often visible on MTM and even bespoke garments, collar gap is something that we have all seen, and too often owned, so to speak. It spoils the entire effect of an otherwise good jacket. What causes it, and how can it be prevented?
Leave aside the way that your jacket collar rises when you lift up your arms – that happens because you are essentially lifting the entire jacket, so logically the collar moves up with the rest of it. What we are talking about here is the way that the jacket collar separates from the shirt collar, unprovoked, when you stand a certain way.
The collar is connected to the whole suit – the shoulders, front and back panels. If they are constructed correctly, the front panels and lapels being constructed correctly, collar gap should not be an issue. If the collar is fairly unstructured, this problem can be avoided, even in RTW jackets, but you can expect it from structured RTW jackets because the way that the front and back are constructed must relate to your shape – for example, if you have backward pointing shoulders, you will need a tailor who can ensure that your coat does not stick up at the back.
Very difficult to avoid in RTW, collar gap can still be an issue with MTM jackets, but if your measurements are correct and the maker is competent, it should not occur. Buyer beware.