In this blog post, we will talk about, “How to soundproof a flat roof?” and discuss the common types of flat roofs. We will also discuss 5 common causes of noisy flat roofs and 7 ways to soundproof a flat roof.
How to Soundproof a Flat Roof?
Luckily there are numerous ways to soundproof a flat roof and cancel the annoying sounds coming from above. You can soundproof a flat roof in the following ways;
- Add Soundproof Drywall Ceiling
- Add Double Drywall Ceiling
- Install Floating Ceiling Joists
- Use Green Glue Sound Damping Compound
- Soundproof the Floor Above
- Use Mass-Loaded Vinyl
- Add Decoupled Flat Roof
Flat Roof and its Types
There usually are two types of flat roofs; Drywall flat roof and suspended flat roof. The two types have different structural properties and require different insulation techniques.
Drywall Flat Roof
A drywall flat roof or ceiling is naturally-built to soundproof the home from above. Made from gypsum, it is different from other common ceilings made of fiberboard, plywood, and hardboard.
The biggest difference lies in its sound-insulation properties and ease of installation. They aren’t just naturally soundproof but are also inexpensive and easy-to-install.
Suspended Flat Roof or Drop Ceiling
A suspended flat roof or drop ceiling is an aesthetically-pleasing alternative to a drywall flat roof. Hanging elegantly from the main ceiling, they are designed to inject a sense of sophistication.
In simple words, it is an aesthetic addon to the original ceiling and can also be removed at will. These ceilings have built-in decoupling, yet have poor insulation properties.
The light fixtures, ductwork, and other mechanical and electrical connections make them poor in restricting sounds.
5 Common Noise in a Flat Roof
The five common noises in a flat roof are roof banging, raindrop noise, heat-relating cracking, creaking, and snapping. All these sounds are fairly common with flat roofs.
- Heavy Rainfall Noise
- Thermal Cracking Noise
- Popping and Snapping Sound
- Creaking Sounds
- Banging Sounds
Heavy Rainfall Noise
Heavy rainfall noise can cause a nuisance especially in the middle of dark, stormy nights. Raindrops falling on the roof’s surface can disrupt peace and make it hard to sleep.
Luckily, you can mute this disturbing noise to a great extent with the use of the right materials and insulation techniques on the ceiling. Additionally, you can also erect a shade cloth on the roof to dissipate the raindrops.
Thermal cracking is heard when the roof shifts its position. A rise in temperature causes the roof material to expand under heat. To cancel thermal cracking, many builders often use expansion joints. Vents, and reflective white paint.
Popping and Snapping Sounds
Popping and snapping sounds are heard in homes and buildings where a flat roof is installed over the existing roof. These sounds are produced when the old roof cracks under the weight of the new flat roof.
Hearing popping and snapping sounds from above is scary, to say the least. There’s nothing much that can be done about these sounds other than ripping off the old roof.
Creaking sounds are common in both peaked and flat roofs. Similar to cold-related or thermal cracking, creaking occurs due to a temperature change. The most cost-effective way to cancel these sounds is to add expansion joints to your roof.
Banging sounds are heard when your roof is not properly installed. You may hear these sounds at different times during the day. Inspecting and fixing the loose parts of the roof will resolve this noise problem.
7 Best Ideas to Soundproof a Flat Roof
Soundproofing a flat roof is relatively easy as its design permits using multiple soundproofing techniques at once. Let’s explore 7 best ideas to soundproof a flat roof;
Add Soundproof Drywall Ceiling
A single drywall layer is usually inadequate to block sounds. Its lightweight permits the passage of sound waves through the studs ultimately to air cavities in the ceiling.
That’s why it is better to opt for soundproof drywall that is relatively thick and naturally-built to insulate homes. However, a soundproof drywall ceiling is 4 times more expensive than ordinary drywall.
On the contrary, you can also insulate the existing single-layer drywall with adequate soundproofing or sound-absorbent material such as mineral woof, fiberglass, and Rockwool.
Add Double Drywall
A double drywall ceiling is a widely preferred solution to soundproof the ceiling against both airborne noise and impact noise. Its thicker setup with an insulating material in between makes them the best in absorbing sounds.
Install Floating Ceiling Joists
Floating ceiling joists is a common soundproofing technique that functions through sound decoupling. Used commonly with drywall ceiling, they effectively block impact noises.
Floating ceiling joists are installed by adding new joists 2 inches below the original ones. The middle space is then filled with insulation material to block both airborne and impact noises.
Use Green Glue Sound Damping Compound
A double drywall ceiling does effectively curtails impact noises, however, they are ineffective against airborne ones. The best way to fix this is by using a green glue sound damping compound. This idea works exceptionally work for blocking both airborne and impact noises.
Additionally, you can also add a third layer of drywall and insulate it up with green glue sound damping compound to relish ever better insulation.
Soundproofing the Floor Above
Rather than tearing apart your ceiling and rebuilding a new insulated one, you can try soundproofing the floor above. The flooring of one makes the ceiling of the other and this is an ingenious way to reduce sounds at the source.
Acoustic underlayments work the best to soundproof floorings alongside acoustic mats. This is a relatively simpler, economical, and effective way to soundproof your ceiling.
Use Mass Loaded Vinyl
Mass-loaded vinyl is an excellent alternative to the Green Glue Sound damping compound and functions the same way. Composed of barium sulfate and vinyl, it is high density, heavyweight yet still, flexible.
Mass-loaded vinyl is also commonly used as floor underlayment and effectively blocks all airborne sounds. However, it is relatively more expensive than the Green Glue sound damping compound.
Add Decoupled Flat Roof
A decoupled flat roof is a system of insulated double-layer ceilings with a Green Glue sound damping compound. Sound clips and hat channels are used to add decoupling to this system.
To add a decoupled flat roof, you would need to remove the existing ceiling. Afterward, soundproofing clips are used to clasp the channels fairly apart from drywall and joists. This is done because if channels are in contact with the joists, their soundproofing characteristics are impeded.
Generally, it is best to fix these channels at 10 inches apart. The next step is to determine the number of hat channels required by measuring the joists. A hacksaw can be used to divide the pieces before application.
The hat channels are placed with a larger flange pointing downwards and the smaller flange facing the roof. Following this, you need to connect soundproof clips with the hat channels to avoid noise vibrations transfer through fasteners and screws.
This process starts from one end and moves forward towards the other. These hat channels can also be fitted near the light fixtures. After its completion, all you need is to place the double layer of drywall.
Using all four methods of soundproofing, this technique is perhaps the most efficient in soundproofing a flat roof.
In this blog post, we talked about, “How to soundproof a flat roof?” and discussed the common types of flat roofs. We also discuss 5 common causes of noisy flat roofs and 7 ways to soundproof a flat roof.
Frequently Asked Questions (FAQs): How to Soundproof a Flat Roof?
How do you soundproof a flat ceiling?
You need to practice ingenuity to perfectly soundproof a flat ceiling. The best way to go about it is to add acoustic insulation material into the false-ceiling.
A false-ceiling is built underneath the existing ceiling and gives you the space you need to add the insulation material. This is one of the most effective ways to soundproof a flat ceiling as it gets the job done without disrupting the original structure.
Besides this, a false-ceiling is also an aesthetic design element and its inclusion can breathe life into your room.
Can you soundproof an existing ceiling?
Yes, there is a way to soundproof an existing ceiling. To do so, you need to add insulation material between the joists in a ceiling. This is an effective way to soundproof a ceiling by filling the cavities in the joists with insulation material.
To find the location of joists you would need a stud finder device. Once you have located the joists, you need to drill a small hole into the ceiling to access the joist space and insert the insulation material.
Why does my flat roof creak?
If you hear your flat roof creaking, it is probably because your builder left no space for joints & materials to expand or contract. Creaking is fairly common both in peaked and flat roofs.
This creaking is mainly due to the lack of space available to the roof materials to adapt to evolving temperatures. During the hot season, it is natural for the roof materials and joints to expand while in the winters, they contract.
A good builder always leaves provisions for the material to expand or contract as it only happens by a certain estimated degree.
How do you soundproof a roof?
You can soundproof a roof in numerous different ways. Each soundproofing idea and technique has its pros and cons. Sometimes you may even have to use multiple ideas in conjunction to achieve the desired result. Here are a few roof soundproofing ideas;
- Insulating the Attic
- Using Roof Underlayment
- Choosing the Right Roofing Material and Shape
- Insulating the Ceiling
- Insulating the Walls
- Proper Roof Maintenance
How do I stop the rain noise on my roof?
To stop rain noise on your roof, you need to build a silent roof. It is a type of roof that can help you reduce the rain noise significantly. A silent roof is built with materials that shatter the raindrops on its smooth surface and dampens the impact. This ultimately causes a drastic reduction in the rain noise.