How to Seal Exterior Barn Doors

The popular sliding barn door is often used to separate interior rooms—both as a functional element and as a display of farmhouse style. But if you’re using a sliding barn door as an exterior door, there are a few extra steps you’ll need to take in order to make sure your sliding barn door is fully sealed and secure.

Connect a Top Shield/Rain Guard
Add a Seal to the Door Edge
Install Top and Bottom Brushes
Install Latches

It’s always important to make sure any exterior sliding door is sealed and secured appropriately—both for safety reasons and to effectively seal out exterior elements, like wind, rain, and extreme temperatures. Effectively sealing exterior doors also offers protection against unwanted pests, and can make sure energy use costs stay as low as possible.

The situation can get a little more complicated when using a modern barn door for exterior purposes. Exterior barn doors can be difficult to tightly and effectively seal—after all, they were originally designed for use on the exterior of barns that were drafty; where a small amount of wind getting in through or around the door did not cause major issues.

But with today’s expansion of barn doors to include other structures, like garages and even homes, the demand to effectively seal out the elements has increased. Most exterior doors are required by local building codes to employ some sort of weather stripping—a way of sealing the exterior barn style door against outdoor elements. Though, weatherstripping isn’t typically included in a barn door kit.

Before you start your weatherstripping project, make sure you’re clear on what local building codes require so you can plan accordingly. And if you’re using a wood barn door, you may have a head start since a wood barn door is naturally more insulative.

How to Seal Exterior Barn Doors

Let’s take a closer look at the specific steps you should take to make sure your exterior barn doors are fully sealed against outdoor elements.

1. Add a Seal to the Door Edge

First, observe the gap when your barn door is closed. Is it tight and uniform?

If you can see more than a quarter inch, at either the upper or lower edge of your door, it’s a good idea to attach a wood shim to close it. Make sure to use a material that is rot resistant—cedar and treated lumber are both solid choices that will last for the long haul. After that, you need to install a rubber gasket.

This is easier than it sounds, and gaskets designed for garage doors are surprisingly great for this. They’re available at most hardware stores and lumberyards. No matter what you use, though, it’s important to make that the gasket squeezes downward when the wood barn door is opening and closing.

2. Install Top and Bottom Brushes

When it comes to sealing the upper and lower edges of your sliding barn door, things can get a little tricky. The top and bottom of an exterior sliding barn door are the best opportunities for cold drafts to pop through, and the greatest challenge to your interior comfort. You need to effectively prevent drafts, but any seal you use also has to allow for easy barn door opening and closing. Sometimes, a simple brush seal added to the top and bottom of your barn door may be all you need. But if you need a stronger seal, you can install a backing strip along the floor.

Another option for a bottom seal is an inverted U channel. It will keep the door from being blown back and forth when it’s partially open, and it also helps trap air. When you combine a U channel with a brush, the result is an excellent, airtight seal that helps you regulate your interior temperature.

You can find brush seals in several different sizes, so you’ll need to figure out how long the bristles need to be for your particular door. This is fairly easy to do, too. While the sliding barn door is closed, measure the space between your door’s bottom edge and the floor. Then buy twice the length as the width of the door slab to make sure you can affix the brushes to both the upper and lower edges of your door. You may even want to get a little extra to account for any cutting mistakes. Then, take the brush’s metal flange and attach it to the lower edge of the sliding barn door; you should be able to screw it in. Do the same thing for the top of the sliding barn door. Once you’re finished, the barn door should still easily open and close without sticking.

Another pro tip: if you’re not too worried about the way it will look, or you’re on a budget, you even can use strips of carpet instead. Just cut the carpeting about two inches wider than the widest part of the gap. Then, use a solid wood backing strip to affix the carpet strips to the exterior door.

3. Connect a Top Shield/Rain Guard

One of the most important reasons for sealing your exterior sliding barn door is to keep it safe from moisture, and to prevent moisture from accessing the interior of your home or other building. The first step in sealing your barn style door is to install an inverted gutter or aluminum flashing to keep moisture off the barn door track. When this water freezes, it can make opening your exterior door more difficult, if not downright impossible in extreme weather conditions. You’ll want to make sure to use silicone calk to seal the space between the flashing and the exterior structure so that moisture can’t get in, potentially causing the wood to rot.

4. Install Latches

Latches are one of the most important parts of a door. A good latch will help your sliding barn door pull tight against your seals, but it may not be included in a typical barn door hardware set.

A toggle latch on each side of the door panel is a good, functional option, and if you can install them on the interior of your structure, that will keep them from being exposed to the elements. This is especially important if you live in a climate where they could potentially freeze if they’re installed on the outside of the structure. Once the latches are in place, they should squeeze the seals you’ve installed to create an airtight seal when the barn door is closed. If you purchased an adjustable latch, be sure to set it to its widest opening it, and then tighten to seal the door once latched.

If, at this point, you can still feel the wind through your sliding exterior barn door, don’t worry. There’s more you can do to shore up any openings where air can get through. If there is even a tiny space between the edges of your sliding barn door and the side of the building, keep tightening the latch. You may even choose to add a second latch, which will help you get an even better seal.

If you still feel a draft coming in through one of the exterior barn door corners, you can use leftover brush material or carpeting to fill the space. You also can fill small gaps along non-moving surfaces with foam insulation or silicone caulk. Keep working on the problem until you reduce the drafts as much as much as possible.

How to Secure an Exterior Sliding Barn Door

In addition to keeping drafty air and rain from getting in through your exterior sliding barn door, you’ll also want to make sure the door itself can safely and securely be locked. Exterior sliding barn doors do not typically feature locks as part of the barn door hardware, and the very nature of barn door construction makes them difficult to lock—but it’s not impossible.

For starters, you can outfit it with a hook and eye lock. This is a simple lock that gets the job done, but isn’t as secure as other options. Hook and eye locks are easy door hardware to install—they don’t require any specialized tools, and can be placed at just about any angle. They also are widely available from just about any home improvement or hardware store. A key point to remember when installing a hook and eye barn door lock, though, is you must make sure there’s absolutely no gap between the barn door and the building. Otherwise, it’s too easy for someone to unlatch the lock.

You also can install a single-cylinder rim lock that can be used from the inside or outside, which is a more secure option. These barn door locks often require more effort, and sometimes even specialized tools to install, so it may be worth it to hire a professional. This type of lock is generally the most secure for a sliding barn door—it can be locked with a key from the outside, and you can lock and unlock it simply by turning the lock with your fingers from the interior. Some people also opt for a simple latch-style lock, but keep in mind that this type of lock is generally used for an interior barn door. You can find latch-style locks in multiple sizes and colors, and they generally are a fairly simple hardware kit to install.

If you only need to secure your exterior barn door from the outside, another simple option is to use a hasp and padlock combination, which is a very easy hardware kit to install and is an affordable option.

Exterior Barn Doors Can Be Both Secure and Beautiful

Sealing your exterior sliding barn door from frozen, drafty winds, inclement weather, and potential pests is crucial to maintaining the comfort an energy efficiency of your interior space.

If this is your first time installing and weather-proofing an exterior sliding barn door, our experienced and knowledgeable team at BarnDoorHardware.com can help—from barn door pulls to custom barn doors, locks, latches, door tracks, the right barn door hardware kit and more, we can help you choose what you need to create a profound farmhouse style statement while keeping your interior space cozy and protected against the elements.

We can’t wait to hear your barn door ideas, so give us a call today.