Do you ever wonder what’s really inside the doors in your building? Do you know the difference between a hollow core door and a solid core door? We’re going to answer your basic questions, as well as make sure you know how to soundproof the solid core doors in your space.

Doors don’t just let you in and out, they are a weak point for sound because of the air they let in around the perimeter and along the bottom. And we all know how distracting noise can be in the workplace. This is where soundproofing technology comes in. When you fix the weak points in your commercial building- whether it’s school, office or warehouse doors, unwanted noise can be gone for good. The best part is we have all the tools and information for you to soundproof solid core doors by yourself!

What Is a Solid Core Door?

A solid core door is a door with a solid interior, whether that’s wood or some sort of composite material. There are a ton of varieties of solid core doors, with many different constructions and species of wood. A solid core molded door utilizes a stamped door skin that is framed and pressed together around a solid core composite. A wood veneer door will have a wood facing, and then a different solid wood interior (typically a cheaper wood). A solid wood door will be solid wood all the way through of the same wood species – no veneer face. The solid core molded door will typically be the most affordable and the solid wood door the most expensive. All of these options are a good base for a soundproofing project.

All of these doors are much better for soundproofing because they are more dense – typically weighing 40-60 lbs depending on the type of door, the door dimensions (length, width, thickness), and the wood species. There are two key factors to making a door soundproof: (1) dense material and (2) airtight installation. When picking your solid door, the heavier the better from a soundproofing perspective. We’d recommend finding the heaviest door that matches your budget as well as your aesthetic.

Solid Core Door VS Hollow Core Door

All solid core doors are heavier than hollow core doors – making them significantly better for soundproofing. Exactly how much better is measured by an STC rating, or Sound Transmission Class, which is a single number that describes how much airborne sound a barrier is able to stop.

A hollow core door is much cheaper and very common in residential homes. Typically, a hollow core door will have an STC rating in the low 20’s, because it only ways 20-30 pounds. Even if you seal up the gaps, a hollow core door is too light to be soundproof.

A solid core door is going to have a much sturdier construction and an STC rating of 30 or more. It’s also a much better base to start from for soundproofing, as the STC rating can be substantially improved with a soundproof door kit without sound going through the door panel itself.

It's paramount that the difference between the two door types is understood. Here's. quick explainer:

How to Soundproof a Solid Core Door

Let’s take a solid core door and turn it into a high performing soundproof door! Here are the steps needed to make that ump:

1. Measure your door
2. Purchase and Install our Sound Lock Door Seal Kit

A standard door can have as much as one square foot of airspace around the edges. Imagine if you had a 12" x 12" hole in your wall. It wouldn't block very much noise, would it? The Sound Lock Door Seal Kit is the durable and effective solution to turn a solid-core door into a soundproof door, increasing the STC rating up to a 51. By sealing up the perimeter and the gap at the bottom of the door, you will substantially increase how much sound is blocked by a solid core door.

If you need ever better sound blocking than that, check out one of our Sound Lock Soundproof Doors. And then in the rare case where the adjustable seal kit won't fit your door, we also offer a door gasket soundproofing kit with our gasket tape and a soundproof bottom seal all-in-one kit.

How to Measure Your Solid Core Door

Installing a Sound Lock Door Seal Kit is easy enough to DIY, and only requires several tools. Before ordering a kit, measure the size of your door to make sure the kit you get fits appropriately. To measure your door, open the door and measure the distance from the floor to the top of the door frame. Write it down.

Next, measure the width of the door frame across the top frame. Write it down. And finally, double check your measurements to ensure you get the correct sized kit. The bottom seal should only be cut a maximum of 2’’, while the perimeter seals can be cut any amount to match the door jambs.

Interested in learning more? We have a lot of soundproofing resources, like our door soundproofing cost article, as well as all our other help guides. As always, we are more than happy to answer all of your questions and help you get the right tools to make your business or home as peaceful and quiet as it can be!

Door Soundproofing Guide

How to Soundproof a Hollow Core Door