DIY under hood insulation requires the use of various recommended automotive sound-deadening materials to achieve maximum effectiveness.
The best part is that you will be soundproofing your car against engine noise, insulating it from high & low temperatures.
If you notice that your car engine getting loud over the years of usage, the most common culprit is often a worn-out under hood insulation.
This insulation, also known as a hood liner, can become damaged over years of usage.
Even worse, some cars don’t have insulation.
How DIY Under Hood Insulation Works
There are two options when it comes to insulating the hood of your car.
You can either use sound-deadening materials or hood liners.
There’s not much difference between the two products, but you get more than one benefit with sound deadening mats.
The primary purpose of sound deadening mats is to provide acoustic insulation but have a bit of thermal insulation.
On the other hand, hood liners are mainly designed for thermal insulation, and some provide a bit of acoustic insulation.
Factors to Consider When Choosing A DIY Under Hood Insulation Material
Below are some of the most important factors to consider to ensure that you get the best material for insulating the hood of your car.
Mass and Thickness
A good acoustic and thermal insulation material must be thick and have more mass.
The thicker the material, the better it will be in terms of thermal insulation.
On the other hand, the more mass, the better the material will be in acoustic insulation.
Cost and Ease of Use
As the saying goes, you get what you pay for.
This strictly applies in this case and the higher the price, the better the quality you get.
However, some budget materials will get the job done effectively nonetheless.
The product you choose must be easy to install DIY.
Luckily, most of the materials feature a self-adhesive backing that makes the installation process much easy.
It is also important to note that some manufacturers sell their products in rolls and others in sheets.
The one you choose will highly depend on the size you need insulation done.
The Best DIY Under Hood Insulation Materials on the Market
Below are my most recommended materials that you can use to insulate your car. Let’s have a detailed review of each material.
Sound Deadening Mats
These are the best choice if you’re purposely looking to acoustically insulate your car.
This is because they are primarily designed for soundproofing and offer thermal insulation as an extra benefit.
Most of these sound deadening mats have mass-loaded vinyl, which helps add more mass hence attaining their acoustic qualities.
Alternatively, dense foam is used as an alternative to mass-loaded vinyl, and while this does its job perfectly, it cannot be compared to the effectiveness of MLV.
Most of these mats have a layer of aluminum foil which helps in thermal insulation.
Dynamat & Noico
Dynamat is one of the most popular brands out there and one to go brand when looking for anything car soundproofing.
This brand offers several different products for different insulating parts of your car.
It’s made from high-quality foam with an aluminum upper surface and an adhesive backing for easy installation.
The product comes in sheets and not in rolls.
One of my most recommended Dynamat sheets is the Dynamat 10465 Thick Self-Adhesive Sound Deadener.
On the other hand, we have Noico.
It meets all the criteria for acoustic insulation.
The best part is that the product works on any surface and can be used to cover all the useful parts of your car, including the floor, roof, hood, doors, etc.
Noico is user-friendly and relatively easy to install.
The product is covered in a special embossing- a feature that indicates whether the product is installed correctly or not.
Another perfect option is the HushMat.
This mat is made from mass-loaded vinyl and features an aluminum foil front hence providing thermal and acoustic insulation.
According to the manufacturer, the product gives 40% heat loss insulation.
As earlier mentioned, hood liners offer thermal insulation purposes, with acoustical benefits.
Most of the hood liners are made from foam instead of mass-loaded vinyl, but that doesn’t mean they don’t offer acoustic benefits.
Additionally, most of the hood liners are available in sheets and not in rolls, making them easier to install.
They have a self-adhesive backing that will permanently stick to any panel of the car where you install it.
Dynamat Hood Liner
Besides producing sound deadening mats, Dynamat also manufactures Hoodliners.
One of my most recommended hood liners from this company is the Dynamat 11905 Hoodliner Thick Self-Adhesive Sound Deadener.
It’s dense and thick, making it perfect for both noise and thermal insulation.
The product is also easy to apply. However, I would highly recommend you take the correct measurements before cutting it for installation.
Another perfect example is the Fatmat Hoodliner.
However, this product is made from acoustic foam- read my guide on installing acoustic foam.
The upper surface is reinforced with aluminum foil which significantly helps in thermal insulation.
One of my most recommended Hoodliner from this brand is the FatMat Thick Self-Adhesive Automotive Sound Deadening Hood Liner.
The solid adhesive backing ensures that the product sticks permanently, giving maximum benefits.
Final Thoughts on DIY Under Hood Insulation
DIY under hood insulation doesn’t have to be a complicated process.
As you can already see, the above products are easy to install and fairly affordable.
If your main aim is to get rid of the engine noise, sound deadening mats are the perfect option.
For thermal insulation, get hood liners.
Hi, my name is Todd R. Bressler and I am the founder of this soundproofing blog. I’m a DIY enthusiast from Cincinnati, the city that just beat New York for the City That Never Sleeps Award in 2020. (Original) I have been in the DIY soundproofing industry for close to 5 years, running a YouTube channel and a Podcast show every Saturday. I started Crafty Soundproofing to help you learn the basics of “self defending yourself against noise”
Have an idea worth sharing? Please contact me and I’ll be happy to respond ASAP.