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DIY Under Hood Insulation: Complete Sound-Deadening Guide

Silent Home Hub DIY Under Hood Insulation

It can be a little concerning when it seems like your engine noise is getting louder after a couple of years.

The worst part? Driving in peace becomes impossible.

But the great news is you won’t have to get a new engine.

The culprit may just be faulty hood insulation, or it could mean that your hood insulation is wearing away.

You’re just going to need a few materials to solve your problem and prepare for a Do-It-Yourself project.

Table of Contents

First Step: Check If You Already Have Insulation Installed Under Your Hood

Not all cars are manufactured with insulation under the hood. To see if your car has a hood liner, check under your hood.

If you find any foam or fabric on the inside, then your vehicle has hood insulation.

Hood liner insulation can wear away after long periods of use. It happens to all cars, and checking for it is part of good car maintenance.

If not, then the next section below will explain how to install one with the right materials.

How to Fit Your DIY Under Hood Insulation

Fitting the DIY insulation is relatively straightforward. These products and materials are easy to install with simple-to-follow instructions.

What’s more important and tedious is appropriately prepping the area and the product/material for the best results.

Let’s get started.

Step 1: Prep the Area

If your vehicle has been fitted with one, remove any existing hood insulation. Even if it’s not worn, you still need to remove it before fitting a new one.

It should come off easily; if not, then use a utility knife gently on the corners, then peel the rest off by hand. You want to use fewer tools so as not to damage the paint job.

Next, be sure to clean up any dirt, dust, or debris from the hood. If there is anything stuck, it won’t be easy for the insulation to adhere.

Step 2: Prepare Your Insulation

Keep your product as clean as possible when you are prepping it before sticking.

Try laying down a tarp, then use a utility knife or large scissors to measure and cut the insulation into shape.

Cutting before sticking will allow you to correctly measure your hood and the product to ensure it sticks well.

It will also be easier to custom fit the pieces to any shape of your hood beforehand rather than having to fix anything up after sticking.

You may also use your old hood insulation, if you have one, as a template. Trace the shape of the old insulator to the new one, then simply cut out the shape.

Step 3: Stick It On

Because these products are DIY friendly, adhering them to the car is fairly straightforward. Simply peel the self-adhesive backing from the product and lay it flat onto the car surface.

Be sure to lay it as smoothly as possible; you can start from one side then smooth it over to the other side.

The goal is to get it in one go.

The self-adhesive is usually very strong, making it not only difficult to remove but also taking it down and reapplying the same piece will have it lose its initial stick.

If you must, cut out a new piece, and start again. Make sure the surface is entirely clean, and attach your new piece carefully.

Step 4: Make It Neat

When everything is stuck to place, you can remove any overlaps with a sharp knife.

Make sure to cut away with precision so that the pieces don’t have any gaps between them. You do not want any noise or heat to escape from the inside.

Should you feel the need to, you can apply as many layers as you want by simply repeating this process.

Types of Under Hood Insulation

Before moving forward with your DIY under hood insulation project, it is best to know first the types of hood insulators available to you and their purposes.

The two main options you have for DIY under hood insulation are sound deadening mats and hood liners. These don’t offer too much difference other than the primary insulation that they provide.

  1. Sound deadeners focus on acoustic insulation, canceling out noise better while still possessing a thermal insulation property.
  2. Hood liners are better at thermal insulation, while their acoustic insulation properties depend on which brand you choose to use.

Sound Deadeners for Sound Insulation and Engine Noise Reduction

If you prefer a liner with a greater noise-canceling feature, go for a sound deadener. Sound deadening mats are easy-to-find products built for soundproofing.

Hood sound deadening mats usually use a mass-loaded vinyl or something similar.

This product is also called limp mass, and it is perfect for soundproofing because it is heavy and doesn’t vibrate when sound waves hit it.

Though most sound deadeners use this, other sound deadening products may use dense foam as their base. It is not as effective at sound insulating as mass-loaded vinyl, but it does work quite well too.

Should you choose to use a sound deadening mat, opt for sound-deadening material with a mass-loaded vinyl base.

Sound deadening mats are also a good option because they are usually fitted with an aluminum foil layer. This layer faces the engine side keeping the engine heat away from the hood, giving a thermal insulating feature as well.

1. Dynamat

Dynamat is a well-known and highly recommended brand for DIY under hood insulation. The brand offers plenty of options for insulation on different parts of your car, depending on your need.

The best thing about Dynamat?

Their sound deadening mats are self-adhesive, which means you will not have to spend extra money and effort on additional adhesive materials or installation.

This product is made with high-quality, heavy, high-density foam with an aluminum sheet in the front for that extra thermal insulation.

Placing these under your hood will even quiet noisy lifter ticks in your engine!

2. Noico

Noico sound deadening mats are also perfect for DIY under hood insulation. They are highly recommended and reviewed as working just as well as Dynamat for half the cost.

Noico sound deadening mats also have self-adhesive properties making them reasonably easy to use.

The Noico product is made of thin but dense sound deadening material, and it fits on nearly any surface of your car.

If the sound is coming from under the hood or on the roof, this will deliver reliable soundproofing.

The Noico sound deadener also has an aluminum foil backing on the front to prevent overheating the hood or other parts of your car.

3. Hushmat

Another excellent option for a sound deadener is Hushmat. These mats are made from mass-loaded vinyl, creating a solid soundproofing barrier under your hood.

This product also comes with an aluminum foil backing, like all the other sound deadener products, providing noise and thermal insulation.

This sound deadener is also self-adhesive, making it easy to install and easy to maintain.

Hood Liners for Heat Insulation from Engine Heat

If heat-insulating properties are your concern, then finding a hood liner is better for you.

Although hood liners focus on addressing issues with the heat in your engine and vehicle, they also provide soundproofing features.

Hood liners absorb and retain heat because of how close they are to your engine. That heat is kept in the pads of the hood liner.

Car insulation materials are usually high-quality rubber and polyether urethane, which are also enhanced with aluminum. All of these materials work together to create thermal insulating features.

More than protecting your car paint, hood insulators are also useful during colder temperatures.

Since hood liners retain heat, that means less time for the car engine to warm up.

A hood liner is usually thicker than a mat because a hood liner is made specifically for car insulating.

Hood liner insulation materials are heavy, and because of this, they also make good options for an engine noise problem.

1. Dynamat

Dynamat also offers very high-quality hood liners. Their hood insulation materials are dense but easy to apply.

Since a hood panel is never usually flat, to ensure that the liner sticks well, you need to make sure that you have the car hood panel properly measured out before cutting.

Dynamat hood liner is used often because of its affordability and accessibility. Its 3/4 inch thick foam makes it a good choice for heat and sound insulating.

2. FatMat

FatMat hood liner is very similar to Dynamat in terms of quality. However, a FatMat hood liner has better acoustic insulator features. It is made with an acoustic foam material that gives it better soundproofing qualities.

This hood liner also has a peel-off self-adhesive for an easy stick installation process.

Its thick foam base and aluminum foil backing make it an excellent insulator for heat, and it is recommended for colder temperatures.

3. Uxcell

Uxcell hood liners provide car insulation for both noise and heat. This hood liner is made with fiberglass cloth, which makes it efficient for hood insulating.

This product can be used for EVERY part of the car.

However, it is particularly useful for under the hood in the engine compartment. This liner is fully waterproof, and with its aluminum backing, it has excellent heat retention properties.

This hood liner is also thin for easy use while still being thick enough to keep your hood and any surface of the vehicle well insulated.

Combining Both Sound Deadener and Hood Liner

It’s possible to use a sound deadener mat and hood liner at the same time. Although separately they offer noise and heat insulating qualities, why not use both together for maximum efficiency?

Combining the insulators is easy and DIY-friendly since most of the products are self-adhesive. You can simply stick one to the other.

  1. First, cut the material with a utility knife or large scissors – both the sound deadening mat and the hood liner into the proper shape.
  2. Then, remove the protective film or the disposable release liner from the sound deadener.
  3. Install the sound deadener on your hood; this will now be your base. After this, install your hood liner on top of the deadening mat.

Placing the hood liner on top will allow you to benefit from the soundproofing material of the products simultaneously, giving double the car sound insulation while still maintaining heat insulation properties.

How to Choose Material for Your DIY Hood Insulation

These qualities are starting points for finding the perfect product/material for your needs, making it easier to separate them by these qualifications to choose which one will work for your specific requirements.

1. Thickness

A thicker mat will work better for insulating, whether for heat or sound, instead of a thinner mat. It will also last longer because it can withstand wear and tear better.

2. Easy to Install

Go for a user-friendly product. Most DIY hood insulating products are easy to use. They will have a self-adhesive backing and are a workable size that is easily cut for custom fitting.

3. Cost

Find a quality product that does not break your budget. Although price usually affects quality, there are many options available that are still a fair price range.

4. Mass

Similar to thickness, a heavier mat or liner is a better insulator. However, a dense mat is not necessarily thick, so you will need to look at the product specifications and choose one for yourself.

5. Amount You Need

Some DIY insulators are sold as sheets while others in rolls. The choice you make will depend on how much you need and for what you will need them.

Do You Need Insulation Under Your Car Hood?

Usually, hood liners or insulation pads are installed for either thermal insulation or sound insulation. More often than not, most products will offer both.

Although it may not seem obvious, they are actually crucial for maintaining good performance in your vehicle.

Most of the noise your car makes comes from engine vibrations.

Several engine parts in your car will move and vibrate when you start your vehicle. All of these can make different sound and noise issues you might want to address.

Beyond causing irritating engine noise, the engine’s vibrations can be worse if they transfer into your car’s body.

The vibrations will create an even louder noise even while you are sitting inside your car.

Hood insulation also offers thermal insulation, which is incredibly important for your car for a number of different reasons.

Although it may not be the most important reason, the first thing is it prevents the hood from overheating and causing heat damage to your car paint.

Damaged paint can seem like a minor issue, but over time it does save some money.

Secondly, and a far more crucial reason to get hood insulation for thermal insulation, is if your car were to catch fire from engine heat.

In the event of an engine fire, the thermal insulation will buy you some more time to get out of your car safely.

Besides car engine noise, hood liners and insulation are more useful than you would first think. DIY hood insulation is easily fitted into your hood, inexpensive, and can be maintained well.

You can also take a look at this video to help you visualize what hood insulation could look like for your vehicle:

Final Thoughts

DIY Hood Insulation is simple, straightforward, and reasonably inexpensive. Where you might find difficulty is choosing among the products and the best material for your car.

However, it will be a good practice to ensure that your vehicle continues to function well so you can use it comfortably!


Changelog:

July 12, 2021 – removed 3 external links, removed 4 affiliate links, embedded 1 YouTube video

June 24, 2021 added changelog, fixed and updated article formatting and content

About the Author

andrea_adams

Andrea has always been bombarded by the hustle and bustle outside her home. Living in the city doesn’t get any quieter. The never ending noise from construction, traffic, and dogs barking on the streets day in and day out drove Andrea to a breaking point.

For 3 years, Andrea committed herself to studying DIY hacks, performing soundproofing experiments, and installing noise-free solutions. Now, she lives a quiet life free of the stress from noisy environments.

She hopes to share this knowledge so that others don’t have to endure the noise reigning in their ears and live a peaceful, stress-free life.