September 19, 2022 / by Danny Mavis

Popping out dents, adding sound deadener or speakers, or replacing aging trim are all reasons for removing your car’s door panels. You’re also going to have to remove the factory-installed moisture barrier before you do anything inside the door. And if you thought it was just a sheet of plastic that the manufacturer had forgotten about, then you need to think again.

Water that finds its way into a door cavity can do all kinds of damage, and plastic moisture barriers prevent it from either getting past the door’s inner frame, or from being absorbed by the door panels. They’re an essential part of your car’s weathertightness, and replacing the panel without reinstalling the barrier will leave you with a wet, mildew mess quicker than you can imagine.

If you’ve removed that protective barrier, you need to replace it quickly. Fortunately, there’s a company right here in Australia that specialises in precisely that kind of material for cars and trucks. They understand better than most the importance of keeping door cavities sealed, and you can order a new car door moisture barrier directly from them online.

Kitted Up to Restore Your Door Barriers

Let’s be honest: once you’ve removed a door panel, the decision to replace your car’s moisture barrier with a brand new one shouldn’t be a difficult one to make. In fact, even if your door panels haven’t been removed, you might still have a very compelling reason to order a high-quality waterproof door restore kit to replace your OE installed moisture barrier.

waterproof door restore kit
Source: enginemaster.com.au

It’s unavoidable that years of heating and cooling cycles will eventually take their toll on all of these thin plastic barriers. And although they may still be effectively keeping condensation, moisture, and dust from passing through to your interior, it’s only a matter of time before the elements turn every door moisture barrier yellow from age, and the mastic adhesive holding it in place into a crumbing mass that’s simply waiting to fall off.

Regardless of whether you’re planning on working inside a door cavity or not, it’s wise to consider replacing your door moisture barriers as a precaution. This is especially true for older vehicles because you won’t know that the old barrier and adhesive have stopped holding until you unexpectedly realise how wet your carpet is. Getting a moisture barrier kit now will save you a load of headaches later.

Moisture Barrier Kit Contents

Door restore kits are sold in 2- and 4-door packs and contain everything you need to reseal the inside of your car or truck doors with an aftermarket moisture barrier that’s heavier and thicker than a costly OE replacement. Respectively, each kit contains:

· Either a 2.4m, or 4.8m package of 650mm wide waterproof plastic barrier material; and,

· Either a 7m, or 14m roll of 6mm x 3mm waterproof butyl sealant tape.

Don’t be fooled, however, by the sparseness of the kits. Depending on the size of your car or truck, these kits generously provide you with enough extra car door moisture barrier adhesive and material to do more than most 2 or 4 door vehicles. Ordinarily, a certain amount of the additional plastic can be used to protect other door-mounted components on either side of the barrier, such as:

· Wires and cabling for windows or mirrors that pass through the barrier;

· Rigid mechanical arms and levers for door locks and handles; and,

· The back sides of door speaker baffles.

Door Moisture Barrier Installation

Once you’ve set yourself to the task, you’ll very likely to find that installing the car door moisture barrier replacement is easier than removing the panel. With the panel off and after you’ve finished any work you needed to complete inside the door, rejuvenating the barrier material is a remarkably straightforward process.

door moisture barrier installation
Source: clublexus.com

· Remove the old barrier.

Along with any brittle remnants of mastic adhesive, silicone, or other attempts at repairing a damaged or deteriorated barrier, completely remove the old one from the inner door frame. Now’s also a good time to clean the inner face of the door, and to make sure that drain holes in the bottom of the door cavity are clear of gunky deposits that could lead to water being retained inside the door frame.

· Apply the new adhesive.

Making sure not to avoid any of the door panel mounting holes that need to go outside of the covered area, apply the kit-supplied mastic to the inner door frame along the path of the original door moisture barrier adhesive. Tearing the mastic’s backing when necessary will allow you to easily shape the adhesive over contours and around tightly radiused curves. And if you also want to cover your speaker baffles, you can apply adhesive inside the door cavity around the speaker hole.

· Remove the adhesive backing.

Lightly run a finger around the circumference of the adhesive strip to ensure that it’s tacked down sufficiently, and then peel away its backing around the entire door.

· Overlay the barrier material.

Carefully extend the moisture barrier out across the door wherever the adhesive’s been tacked. For speaker baffle protection, you’ll first want to cut a small sized piece of barrier material and fix it to the adhesive inside the door cavity. Take note of where any cables, wires, or other attachments would need to attach to the door panel, make small slots in the barrier to allow them to be pulled through, and then firmly depress the full barrier into position against the adhesive along the door frame.

· Trim the barrier material.

Cut the unused portion of barrier material away from the section that’s been used on the door, and then trim the outside perimeter of the tacked section to match the fit of the OE barrier. Pull any necessary cables or wires through the barrier, and cover with another small piece of barrier material for maximum moisture protection.

That’s all there is to it. And when you’re finished, you can put your concerns about mouldy door panels and wet carpets behind you once and for all.

The Final Word

At the end of the day, restoring the inside of your car’s doors to better-than-factory condition is easy and affordable. And it’s also a necessity if you want to protect your vehicle from avoidable water damage. Purchasing a high quality door restore kit is going to help you keep your doors, door panels, and carpets in the best possible condition. It’s a replacement that you’ll be glad you made.