Soudal is good quality but looks like it's been applied with a spatula, the areas where it's shrunk would lead me to think they've used high modulus acetate cure rather than low mod neutral cure, low mod has a higher elasticity this able to expand and contract to a higher degree before it let's go of one surface, high mod smells of vinegar hence why I asked.
Other than that if he thinks there's nothing wrong with the sealant he needs to change careers
And like Notch suggests it's always a better finish if you can foam up then seal and then cloak over to tidy it up, I've done the same on my own house, much neater I think
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