Imagine closing your door and stepping into a peaceful sanctuary.
Even in the closest families, minor conflicts arise from shared living spaces.
For example, mutual interference:
Parents like to watch TV, especially with the volume turned up high…
Family members chat in the living room while you sleep in the bedroom…
Your husband watches the Christmas Super Bowl while you work…
With elderly family members and children around, you can’t fully enjoy intimate moments with your partner in the bedroom…
Even though family members are close, at times like these, it can be quite frustrating!
I just want to close the door and have my own world.
Soundproof doors can provide a quiet, independent space
Sources and hazards of indoor noise
Scientific research shows that people who lack personal space and privacy over the long term may develop various psychological issues: lack of concentration, memory decline, anxiety, and irritability.
So don’t always assume you’re getting old—it might just be too noisy around you!
There are many sources of indoor noise.
These include uncontrollable noise sources such as neighborhood living noise, plumbing noise, and road noise, as well as noise generated within one’s own home.
We have discussed the former extensively before.
How important are soundproof windows?
For those fortunate enough to live in a quiet community with considerate neighbors and a conscientious builder, does this mean they can completely avoid the hazards of noise?
That’s naive. Where there are people, there is noise. If you have a large family…
How noise is formed
Sounds inside a room undergo multiple reflections as they propagate. If there are no appropriate sound-absorbing materials in between, these sounds will be continuously reflected, reverberated, and amplified until they become noise.
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90% of the noise interference between family members is transmitted through indoor doors.
If every room’s door has excellent soundproofing, where would the noise find a way through?
What makes a door truly soundproof?
The following factors determine a door’s soundproofing effectiveness: the material of the door panel, the thickness and density of the door panel, and the size of the door gap.
Door panel material affects soundproofing performance
The soundproofing performance of a door panel primarily depends on the filling material inside the door core.
Low-quality door panels simply use cardboard to roughly partition the hollow core, resulting in poor noise reduction.
Generally, the core of molded soundproof doors is filled with a honeycomb-structured paper base (this is a common phenomenon; honeycomb paper doors are not paper doors, so do not assume they have poor soundproofing). The honeycomb structure allows a certain material to achieve the largest area and highest strength, thereby increasing the door panel’s strength.
The sealed air layer formed by this structure helps with soundproofing.
Doors made using this method can achieve a sound insulation effect of 29 decibels, which is considered average.
Interior doors with particleboard cores offer superior sound insulation performance. Particleboard has significantly higher density and quality than paper-based materials. High-quality particleboard doors can achieve sound insulation performance of 32 decibels, which is notably higher than the 22-25 decibel requirements of some national standards.
This structural design appears simple but is actually ingenious:
- Durable, evenly distributing external forces to prevent deformation;
- Weight reduction: the tubular structure makes bridge-hole mechanical panels 60% lighter than solid wood panels of the same thickness, enabling smoother opening and closing;
- Effective prevention of temperature diffusion, achieving excellent insulation performance;
- Excellent fire resistance: it can withstand flames for 15 minutes in tests, making it the best-performing panel material.
Some of Grandsea’s indoor soundproof doors also use bridge-hole mechanical panels as the core, with solid wood edging, achieving sound insulation performance of 34 decibels, which is quite impressive.
By the way, all the doors mentioned above can be referred to as solid wood composite doors, and this is indeed the official terminology, so it is best to clarify with the salesperson or request a cross-section diagram of the soundproof door when purchasing!
As for solid wood doors with relatively higher prices, their sound insulation performance depends on the density, weight, and thickness of the wood. The higher the density, the heavier the weight, and the thicker the door panel, the better the sound insulation performance.
Solid wood doors are divided into two types:
The first type is solid wood doors, made from natural solid wood sourced from forests, with only one type of wood used in the product and no wood veneer applied;
However, such doors are not only expensive but also have the strongest wood properties, making them prone to warping and cracking, and thus unsuitable for use as doors.
The second type of solid wood door uses a core made of cypress or other mixed wood pressed into density board, with a solid wood veneer applied to the surface. It is then manufactured through high-temperature hot pressing and finished with solid wood trim.
There is also a type of soundproof door: a layer of synthetic leather is wrapped around the exterior of a standard wooden door panel, with rock wool filled inside the synthetic leather. The synthetic leather strips are secured with nails, and the gaps around the edges are sealed with foam rubber strips.
The most familiar type is the soundproof fire-resistant door: the wooden frame of the door panel is filled with sound-absorbing materials such as rock wool, and the exterior is covered with asbestos boards, galvanized iron sheets, and fire-resistant fiber boards. The gaps around the edges are sealed tightly with magnetic rubber strips.
Its door thickness is approximately 70mm, with noise reduction up to 45 decibels. However, such high performance is generally unnecessary for indoor use in residential settings, and excessive door thickness can also complicate installation.
High-quality acoustic doors can match the soundproofing performance of solid wood doors, yet their average price is significantly lower.
If you have specific aesthetic requirements for acoustic doors, we recommend contacting us directly. Grandsea offers personalized customization services to ensure your interior doors combine both beauty and quality.
Regardless of the door type you choose, we can provide relevant data on sound insulation performance.
The patterns on the door are not just decoration
With the rise of minimalist style, people are increasingly averse to intricate lines.
When choosing doors, they prefer ones with no patterns at all, such as white lacquered doors. Some even want the door panels to be invisible.
However, the patterns on doors are not merely decorative.
Soundproof doors not only require sound insulation but also a certain degree of sound absorption.
Observation reveals that most door panels feature simple or intricate patterns on both sides. Some may assume these are purely decorative, but this is not entirely accurate.
If the door panel is perfectly smooth, indoor sound waves would be fully reflected back, creating noisy echoes.
The necessary designs and lines on the door serve to absorb sound and prevent repeated reflections.
Door Panel Thickness and Density
Generally speaking, the thicker the door panel, the higher the density, and the heavier the weight, the better the soundproofing effect.
However, one should not excessively increase the door’s weight in pursuit of soundproofing, as this would overburden the hinges and hinge plates, making it difficult to open and close the door smoothly and affecting its functionality.
Therefore, the best acoustic doors should minimize weight while achieving the required soundproofing effect.
Generally, the thickness of indoor doors ranges from 40mm to 50mm, with a thickness greater than 45mm being optimal.
If the door gap is too large, even the best door is useless
Another extremely important factor affecting soundproofing is the door gap.
Even if the door is made of the best materials, if the gap is too large, it is all in vain, as noise will seep in through the gap.
The issue of door gaps depends not only on the installer’s skill but is more determined by the door’s construction.
There are two types of doors in the world: those with large gaps and those with small gaps.
Doors with large gaps are flat-edge doors: that is, the edges of the door are flat.
Traditional doors are all flat-edge doors. Due to the need for locks to open, there must be a 3-millimeter gap between the door and the door frame, resulting in poor sound insulation.
Doors with narrow gaps are T-shaped doors: this new type of noise-reducing door has T-shaped edges.
The protruding part presses against the door frame and is equipped with a sealing gasket, not only enhancing the door panel’s sturdiness but more importantly improving soundproofing and insulation.
Therefore, if you want a soundproof door, under the same conditions, choosing a T-shaped door is superior to a flat-edge door.
The soundproof door’s secret weapon
Impact-resistant strips
Impact-resistant strips can also be called soundproofing strips, typically made from foam rubber strips or rubber strips.
First, measure the gap between the door and the door frame, then purchase soundproofing strips according to the dimensions.
Some indoor door suppliers, to save costs, only install soundproofing strips on the top and bottom of the door.
If you want better soundproofing, you can ask the supplier to install soundproofing strips on all four sides before placing your order;
for entrance doors, you can even install soundproofing strips on both the inner and outer door frames for immediate results (though this may cause the door to open and close less smoothly).
Silent Door Locks
Sometimes when you return home late, your family is already asleep, and the sound of closing the door wakes them up—this is undoubtedly the most frustrating thing for those who return home late.
Fortunately, there is now a product called a silent door lock, which isn’t completely silent but is significantly quieter than ordinary door locks!
Popular indoor door silent locks on the market include magnetic locks and electronic locks.
Magnetic locks are more commonly used for wooden doors, while electronic locks are more suitable for metal doors.
Some Grandsea solid wood composite doors are equipped with magnetic silent locks, and I’ve personally tested them—the sound when opening and closing the door is extremely quiet and won’t wake someone who’s asleep.
Finally, a brief summary:
◙ Sound insulation performance: Doors filled with soundproofing cotton ≥ solid wood > doors filled with particleboard > doors filled with honeycomb-structured paperboard > doors filled with hollow paperboard.
How to identify the internal materials of these doors?
First, ask: directly ask the salesperson what materials are used to fill the door.
Then request the quality inspection report and review the data parameters.
Second, observe: check the door thickness; thicker doors provide better sound insulation;
check the door flatness; the flatter the door edges, the better the fit with the door frame, regardless of the structure. Any warped door will have poor sound insulation and allow air leakage.
Third, listen: tap one side of the door gently to assess its sound transmission properties. Generally, doors with good sound transmission have poor sound insulation.
◙ Choose doors with decorative patterns on the panels, as they have sound-absorbing properties and better sound insulation!
◙ Pay attention to the size of the door gaps during installation; larger gaps result in poorer sound insulation. Choose doors with T-shaped joints for a tight fit and better sound insulation!
◙ Install door bumpers around the edges of the door to significantly reduce noise!
◙ Doors with silent door locks produce minimal noise when opening and closing, avoiding disturbing family members!
We hope this article is helpful. Ready for a quieter home? Explore Grandsea’s certified soundproof doors—backed by performance data and customizable for your space. As a leading manufacturer of windows and doors in China, Grandsea can quickly provide high-quality products and customized services.
