How to Install an Exterior Door Like a Pro: A Complete Guide for Homeowners
How to Install an Exterior Door Like a Pro: A Complete Guide for Homeowners
Upgrading your home’s exterior door is more than just a cosmetic improvement—it’s an investment in your home’s energy efficiency, security, and curb appeal. Whether you're replacing a drafty back door, upgrading your front entry for style, or addressing rot in the framing, knowing how to install an exterior door properly is crucial.
At Dragonstone Construction LLC, we believe in empowering homeowners with expert-level knowledge. This guide walks you through everything you need to know about installing an exterior door—whether it's pre-hung or you're building out the entire frame.
Choosing the Right Door: Pre-Hung vs. Slab Door Installation
Before you pick up a hammer, let’s talk about the two main types of exterior door installations:
1. Pre-Hung Exterior Doors
These come with the door already mounted in a frame and are the most common choice for homeowners replacing the entire door unit.
Best for: When the current door frame is rotted, warped, or damaged.
Pros: Easier and faster to install, ensures a square fit, usually includes hinges and weatherstripping.
2. Slab Door Replacement
This is just the door itself with no frame included.
Best for: When the existing frame is in great shape.
Pros: More budget-friendly, allows reuse of existing trim and casing, and offers more flexibility with design.
If your frame is compromised, you’ll need a full-frame replacement, making a pre-hung door your go-to option. If your frame is solid and level, a slab might be all you need.
Tools & Materials Checklist
Whether you're DIY-ing or hiring a pro, here are the essential tools for the job:
Tape measure
Hammer
Level
Drill/driver
Pry bar
Utility knife
Caulk gun
Exterior-grade caulk
Shims
Screws
Insulation foam
New pre-hung or slab door
Flashing tape (for water protection)
How to Install a Pre-Hung Exterior Door
Step 1: Measure Correctly
Measure the height, width, and depth of your existing door frame. Don’t forget the rough opening size, which should be about ½ inch wider and taller than the new door.
Pro tip: Standard exterior doors are 36 inches wide by 80 inches tall, but always measure to be sure.
Step 2: Remove the Old Door and Frame
Remove the hinges and pull the old door off.
Pry out the casing and remove the existing frame.
Check for rot or damage around the sill or threshold—repair if necessary.
Step 3: Prepare the Rough Opening
Use a level to check the sill and sides.
Apply flashing tape to the sill to protect against future leaks.
Dry-fit the new door to check alignment.
Step 4: Install the New Pre-Hung Door
Apply a thick bead of exterior caulk to the underside of the threshold.
Tilt the new door into place, pressing it snugly against the framing.
Shim the hinge side first, checking for plumb and level.
Secure the door with screws through the shims into the studs.
Check the reveal (gap) around the door and adjust shims as needed.
Step 5: Insulate and Seal
Spray low-expansion foam around the frame to insulate.
Don’t overfill—this can warp the door frame.
Once dry, trim the foam and install exterior and interior trim.
Installing a Slab Door (Replacing the Door Only)
If your frame is in great condition, a slab door can be a quicker update:
Remove the old door and hinges.
Use the old door as a template to mark hinge placements and handle bore.
Chisel mortises for the hinges.
Install the hinges and hang the new door.
Check for proper swing and clearance, adjusting as needed.
Install weatherstripping and sweep if necessary.
When Should You Hire a Professional?
There are times when it’s best to leave it to the experts. If your rough opening is out of square, or there’s visible moisture or termite damage, you’ll want to call in someone with deep experience. For exterior door installation services that guarantee a weatherproof seal and proper security, a licensed contractor ensures peace of mind.
A poorly installed door can lead to water intrusion, drafts, and energy loss. If you’re unsure, it’s always worth working with experts who’ve done this countless times.
Added Security & Energy Upgrades
While you're at it, here are a few upgrade ideas to consider:
Smart Locks: Enhance security and control
Energy Star Doors: Improve insulation and lower utility bills
Storm Doors: Add an extra layer of protection
Motion Lighting: Boost security around new entrances
You can also see some of our recent work on our Google Business Profile to check out transformations we’ve completed across Branson and Hollister.
Most Asked Google FAQs About Exterior Door Installation
Q1: How much does it cost to install an exterior door?
Costs can range from $500 to $2,500, depending on labor, door style, materials, and condition of your framing.
Q2: How long does it take to install an exterior door?
A pre-hung door typically takes 2–4 hours for a professional. A slab install may take less time if measurements align.
Q3: Can I install a new door in an old frame?
Yes—if the old frame is level, square, and undamaged. Otherwise, a pre-hung door is safer and easier to install.
Q4: What type of caulk should I use for door installation?
Use exterior-grade silicone or polyurethane caulk for long-lasting weather resistance.
Q5: Does a new door increase home value?
Absolutely. Curb appeal, energy efficiency, and security all improve, making this a top ROI project for homeowners.
Final Thoughts
Installing an exterior door is one of the most high-impact home improvements you can make. Whether you choose a pre-hung unit or retrofit a slab door into an existing frame, proper installation will boost your home's security, comfort, and value for years to come. If you have questions, feel free to contact our team for more insights.
Also check out our latest door install projects near you for inspiration and real-life examples.
🛡️ Disclaimer
At Dragonstone Construction LLC, we believe in arming homeowners with the knowledge they need to care for their homes. This blog is provided for general informational purposes and does not replace a professional on-site assessment. For accurate evaluations, installations, or home upgrades in Branson, Hollister, and surrounding areas, contact our team directly. We’re happy to help.