DIY: Weatherstrip Your Doors (Step-by-Step Guide for a Warmer, More Efficient Home)

As temperatures start to drop in Maryland and across the DMV, many homeowners begin thinking about heating bills, drafty rooms, and simple ways to keep their homes warm without spending a fortune. While insulation in your attic and walls plays a huge role, one of the most overlooked sources of heat loss is surprisingly simple: your doors.

Even a small gap under an exterior door can let in a constant stream of cold air—and that means higher energy bills, chilly rooms, and extra strain on your HVAC system. The good news? Fixing it is fast, easy, inexpensive, and completely DIY-friendly.

One of the quickest upgrades you can make is installing or replacing a door sweep—a weatherstripping strip that seals the bottom of your door and blocks cold drafts, moisture, pests, and even noise.

Below is an expanded guide to help you not only install a sweep, but also understand the different types, what to look for, and how to make sure yours lasts all season long.

Why Weatherstripping Your Doors Matters

A properly sealed exterior door can:

• Prevent cold air from entering and warm air from escaping
• Reduce your energy bill (often by 10–15%)
• Improve your home’s comfort—especially near frequently used doorways
• Keep out dust, insects, and even small rodents
• Minimize noise from outside
• Reduce wear on your heating system

For older homes in Central Maryland—Mount Airy, Frederick, New Market, Monrovia, Ijamsville, Hagerstown, and surrounding areas—weatherstripping is especially important because shifting foundations and seasonal humidity can create gaps under doors over time.

Types of Door Sweeps: Choose the Right Fit

Before you get started, it helps to know your options. Door sweeps generally come in three varieties:

1. Standard Metal or Aluminum Sweep

• Most common option
• Features a strip of rubber or vinyl attached to a metal frame
• Very durable and easy to install
• Great for exterior doors

2. Adhesive Door Sweeps

• Peel-and-stick design
• Quick installation, no tools needed
• Good for interior doors or temporary fixes
• Not ideal for heavy weather exposure

3. Brush-Style Sweeps

• Flexible bristles instead of a rubber flap
• Excellent for uneven floors, garage entry doors, or workshop spaces
• Allows smooth movement while still blocking drafts

Choose the style that best fits your door and your home’s needs.

Step-by-Step: How to Install a Door Sweep

1. Clean the Bottom of the Door Thoroughly

Start by cleaning the underside of your door with warm water and mild soap.
This removes dust, dirt, salt, and debris—ensuring your sweep attaches cleanly and sits flush.

✔ Allow the door to dry completely.
✔ If you’re replacing an old sweep, remove it and scrub off any residue or old screw holes.

Tip:
If you live in an older home where the door may be slightly uneven, open and close it a few times and note where the gap is largest. This will help when adjusting the sweep.

2. Measure and Cut the Sweep to Fit

Not all sweeps come pre-cut, and that’s a good thing—you’ll get a custom fit.

• Hold the sweep against the bottom of your door.
• Mark where it needs to be trimmed.
• Use a hacksaw (for metal sweeps) or scissors/utility knife (for rubber types) to cut it down.

Don’t worry if the sweep looks too long out of the package—that’s normal.
You can easily trim it for a perfect fit.

3. Install the Sweep Securely

Once everything is aligned:

• Hold the sweep flush against the bottom of the door.
• Ensure the rubber flap or bristles lightly touch the threshold but don’t drag excessively.
• Screw it into place using the pre-drilled holes, or peel-and-stick if using an adhesive model.

Pro Tip:
Open and close the door a few times to ensure smooth movement. Adjust the height if necessary.

Extra Tips for a Perfect Seal

✔ Check for Side Gaps Too

Weatherstripping the sides of the door (called “door jamb weatherstripping”) can dramatically improve energy efficiency.

✔ Use a Draft Test

At night, turn off the lights inside and shine a flashlight along the door edges from outside.
If you see light coming through… drafts are coming through too.

✔ Don’t Forget Sliding Glass Doors

These often lose the most heat. Adding a sweep or replacing worn rollers can help reduce drafts.

✔ Consider Threshold Upgrades

If your threshold is worn or warped, replacing it can make your new sweep even more effective.

How Often Should You Replace a Door Sweep?

Typically every 2–5 years, depending on:

• Weather exposure
• Door usage
• Material quality
• Humidity changes

If the sweep looks cracked, flattened, or no longer makes full contact with the floor, it’s time for a replacement.

DIY Weatherstripping = Real Savings

Installing a door sweep may seem simple, but the benefits add up quickly:

• Warmer home
• Lower energy bills
• Less strain on your heating system
• A more comfortable winter season

And best of all?
This project usually costs $10–$25 and takes 15 minutes.

If you’re preparing your Maryland home for fall and winter, this is one of the easiest upgrades you can make.

Need Help Getting Your Home Ready for Winter?

If you live in Central Maryland—Mount Airy, New Market, Frederick, Monrovia, Urbana, or the surrounding areas—and want more tips on maintaining or improving your home’s value, Maryland Real Estate Professionals is here to help.

From DIY guides to local market trends, home value insights, and expert real estate advice, we’re committed to helping homeowners stay informed and prepared.