The Spruce picked BELLEZE barn door as the Best Soundproof Barn Door of 2020 because of its solid pine core.
Quote from The Spruce:
"Thanks to its solid pine core, this is one of the more soundproof options available. It’s also one of the heaviest, so it might not be the most convenient pick for a high-traffic area of your home. It’s stained a deep brown color, and is also available in an unfinished version that can be painted or stained to your preference. The door measures 36 x 84 inches.
The door comes unassembled and hardware is not included, so you will need to purchase some separately before the door can be installed. Installing a barn door is a quick and easy DIY project, as they don’t require any major framing, only special hardware."
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