Van Build 4.1: Sound Insulation - So Easy, I Almost Forgot to Post About It!

This is a quick but important post on installing sound insulation. It is the easiest thing you’ll do and it is one of the first things you’ll want to do on the interior of your van. In this post, I’ll go over handy techniques for laying down your insulation and the tools you’ll need.

We decided to:

• use Kilmat,

• install it over the entire floor and wheel wells, and

• covered 30-ish % of the walls, ceiling, and doors

If you want the “why” behind that decision, please read Van Build 4.0: Sound and Thermal Insulation - a Joint Discussion, where I go over all those details.

NOTE: This is a great step to get the kids involved. Depending on your child’s age and strength, they might just be able to help peel the Kilmat sheets OR might even be able to roll. I would just double-check after they were done and re-roll where they didn’t do it strong enough.

Leila did the peeling, I did the sticking to ensure against air bubbles & Dante rolled (I double-checked)

Without further ado, here's the post and a quick disclaimer that there are some affiliate links- I may receive a small commission (at no cost to you) if you purchase through the links provided. (Learn more here) Thanks for supporting On An Imperfect Journey!

Tools

• Rubber roller

• Kilmat (2.5 36 sq. ft. boxes for the 170 extended high-roof - follow the link, it’s still cheaper than buying the exact amount of the 18 sq. ft. box)

• Work gloves - I really like these because they’d help when I’d manually smooth out the Kilmat in corners

• Utility Knife - this one is great - super compact & stores additional razor blades!

Installation for Ceiling, Walls, and Doors (read on for Installation on the Floor & Wheel Wells)

I promise that this will be the easiest thing you ever do in the whole build! Again, please read Van Build 4.0: Sound and Thermal Insulation - a Joint Discussion, where I go over all those details to understand why we placed additional Kilmat over the factory-installed sound deadener.

Tip: wear the gloves during the entire install. The sound deadener has a tar-like substance that is really hard to get off your hands. Also, wear pants you don’t care too much about when doing the floor install.

1. Cutting the Kilmat to size

With the utility knife, cut the Kilmat to size for each panel of the vehicle. You can use the sound deadener already in the van as guidance for what constitutes 25-30% coverage.

Laying down our first piece

Don’t waste sound deadener in those areas you know you will be cutting into (windows, and roof-top vent and A/C cut-outs.

The blue square is where one vent is now installed - no point in wasting Kilmat there

2. Flatten the Kilmat into position

Peel the Kilmat and stick it into position. I would suggest applying it from one side and slowly smoothing it into place to avoid air bubbles.

Use the roller to flatten the Kilmat. It starts with a bumpy surface and once the bumps have been smoothed out, you know you’ve properly rolled and installed it.

I suggest using the larger roller. Since you’re installing the Kilmat on a flat surface, it will go quicker with the large roller.

3. Repeat for every panel, making sure to cover 25-30% of the surface.

You can see the whole ceiling done here.

Note: you will want to remove the coverings on the sliding door, rear cargo doors, and even the front cabin doors and install them there, too.

Note on the sloped ceiling above the front cabin: It is a bit of a hassle to remove the paneling and interior shell in that area. So, since you need to install thermal insulation as well, I would wait until you have your thermal insulation to install sound and thermal insulation at the same time. Also, once you’ve installed everything, if you’re planning on putting an overhead shelf there too, you don’t need to reinstall the black arched frame covering that area.

Installation for the Floor & Wheel Wells

1. Remove the subfloor

Unscrew and remove the entire subfloor. Store in a safe place if you plan on reusing the factor subfloor. Keep track of which hardware goes where to reinstall later.

Since we are installing an entire floor/seat-bed combo that allows us to slide the seat-bed on a track embedded into the floor, we don’t need our subfloor anymore because the installed floor system comes with a subfloor. Still, just showing the different hardware in the different parts:

Note: for this reason, we will not have any posts on insulating the floor. However, I have heard that the insulation doesn’t really help on the floor and what you really need is radiant heating!

2. Clean the Floor

Clean/sweep the entire surface to make sure you’re not rolling over debris, which can cause air bubbles to occur.

3. Roll the Kilmat into place

The floor is a bit trickier because there are so many grooves and bends. I suggest starting from one end of the van and moving your way down to the other end.

If you’re doing what we did and installing it over the entire floor (as a way to protect the floor from moisture), you will want to prevent any gaps. You will notice that there is a thin piece along one side of the Kilmat that doesn’t have a sticky surface. To make sure to prevent gaps, you’ll want that part to overlap with the piece you’ve just put down.

That means start sticking from one corner, moving across until you finish, and repeating all the way through the van. You’ll want to stick the side of the Kilmat piece that doesn’t have the sticky surface first at the corner, then slowly press down across, making sure you press it into the grooves. We did this by slowly rubbing it up and down into place, moving slowly across until the whole piece was laid down.

Then, on the raised parts of the floor, I would use the wide rubber roller to flatten the Kilmat.

In the grooves, I actually found that flattening it with my thumb, especially into the corners of the grooves worked best. You can use the smaller roller but you need to be careful near the edges of the grooves because the sharp corners of the roller can cut into the Kilmat.

4. Laying Kilmat on the Wheel Well

The wheel well obviously doesn’t lend itself to just laying down the Kilmat and rolling into place. You will need to cut pieces to lay over all the curved edges. Just keep rolling them into place, making sure not to allow any air bubbles and ensuring that the pieces of Kilmat join together or slightly overlap.

Here's a video of Dante and I rolling out the Kilmat where you get a good look at the wheel wells! Music choice thanks to Marino.

And you’re done! Next up, I’ll share our plans for our roof-top attic storage/solar mount! Subscribe to get alerts for new posts!