How to Install Double Exterior Doors
Installing a pair of grand double doors can feel like wrestling a bear, but how to Install Double Exterior Doors isn’t rocket science when you follow a proven roadmap. The payoff? Instant curb appeal, improved energy efficiency, and that satisfying thunk every time the new doors latch. In this guide, we’ll walk through each stage—measuring, prepping, framing, hanging, and sealing—using plain language, pro tips, and code-compliant best practices. Stick with us and you’ll open those shiny new doors in no time, saving a chunk of contractor fees along the way.
Pro Tip: Snap photos of every stage. They’re handy for warranties and show-off moments on social.
Tools & Materials Checklist
Before you pry a single hinge, gather everything on this list—nothing stalls momentum faster than realizing you’re a shim short with a door dangling in the wind.
Safety Gear You Need
- ANSI-rated safety glasses
- Cut-resistant gloves
- Hearing protection
- Dust mask (demo debris is no joke)
Essential Tools
Be sure to have a 25-foot tape measure for accurate rough-opening measurements, a 6-foot level to check plumb on tall jambs, and a framing square to verify true right angles. A cordless drill/driver is essential for pilot holes and securing structural screws, while a reciprocating saw helps quickly remove old jambs. Use wood and composite shims to fine-tune the reveal gaps, and a low-expanding foam gun to block drafts without bowing the frame.
Door Components
- Pre-hung double door unit
- Composite or metal sill pan
- #8 × 3″ exterior-grade screws
- Silicone and polyurethane caulk tubes
- Self-adhesive flashing tape
- Premium weatherstripping kit
Preparation Stage
Proper prep makes the difference between a weekend victory lap and a never-ending punch list. Take your time here.
Accurate Measuring
- Measure width between studs at the top, middle, and bottom—use the smallest number.
- Measure height from subfloor to header on both sides—again, note the smaller.
- Subtract ½” from width and ¼” from height; that’s your ideal rough opening for the pre-hung unit.
Removing Old Doors
- Pop hinge pins and lift each slab off.
- Score old caulk lines so the trim comes away clean.
- Use the reciprocating saw to slice nails between jamb and framing; leverage jamb pieces out carefully.
Inspecting Framing
Before installing the door, carefully inspect the framing for any signs of rot, water stains, or damage that could weaken the structure. Check the openings to make sure they are square and true, as out-of-square frames will cause installation problems later. If you find any uneven studs or high spots, sister new studs or plane them down to ensure a flat, consistent surface for the door frame.
Installing the Door Frame
Now the fun begins—dry-fit first, fasten second.
Setting a Sloped Sill Pan
A sill pan is essential to direct any water away from the interior of the building and prevent leaks. Apply a generous bed of silicone sealant under the sill pan and create a back dam lip to hold water away from the subfloor. For added protection, overlap flashing tape over the subfloor and onto the sill pan, giving extra peace of mind against water intrusion.
Aligning & Shimming
Place the door frame loosely into the opening and use shims near each hinge location to begin the alignment process. Check that the frame is plumb (vertically straight), level (horizontally even), and square (corners at 90 degrees) before making any final adjustments. Continue adjusting the shims until the door reveals—the gaps around the door—are consistent and even on all sides.
Fastening the Frame
Start securing the frame by driving 3-inch structural screws through the hinge jamb where the shims are placed, making sure not to over-tighten and cause the frame to bow. The screw heads should be just flush with the surface, providing firm attachment without distorting the frame. Before continuing with the rest of the fasteners, double-check the door’s swing and alignment to ensure everything moves smoothly.
Hanging the Double Doors
With the frame rock-solid, the slabs slide into place like butter (well, almost).
Adjusting Hinges
Start by hanging the passive door first, ensuring it swings freely and the latch aligns perfectly with the strike plate. If the door doesn’t sit just right, add or remove thin shims behind the hinges to achieve a consistent ⅛-inch gap, known as the reveal, between the door and the frame. This fine-tuning prevents rubbing and ensures the door closes smoothly and evenly.
Checking Clearance
With both doors closed, inspect the seam where they meet to confirm there’s no light filtering through, indicating a tight fit. If the door sweeps are dragging on the floor, carefully trim them to maintain clearance without sacrificing protection against drafts. Using a nickel as a quick gauge helps ensure there’s an ideal small gap, allowing the doors to operate without sticking.
Final Fastening
To secure the doors firmly and prevent future sagging, drive two 3-inch screws through the top hinge leaf into the surrounding framing. These screws are hidden behind the hinge and provide strong reinforcement that supports the door’s weight over time. This final step ensures the doors remain stable and functional for years to come.
Sealing & Insulating
Even the prettiest install leaks energy if you shrug off this step.
Low-Expanding Foam
Apply a thin bead of low-expanding foam between the jamb and the framing to fill gaps without causing pressure damage. Let the foam fully cure before trimming it flush to the surface for a clean, professional finish. Avoid using high-expansion foam, which can warp or deform the frame and compromise the installation.
Weatherstripping
Use the factory-installed weatherstripping or upgrade to a high-quality, high-compression silicone seal for better protection. This upgrade is especially valuable during heavy rain or monsoon seasons when strong seals prevent water and drafts from entering your home. Investing in superior weatherstripping pays off by maintaining comfort and preventing moisture-related damage.
Exterior Flashing
Install self-adhesive flashing over the flange first, then cover it with house wrap, always overlapping layers in a shingle-style from bottom to top. This method directs water away from the structure, preventing leaks and moisture buildup behind the siding. Finish by applying a neat bead of color-matched polyurethane caulk around the perimeter to seal edges and enhance durability.
Finishing Touches
Installing Hardware
Mount handle sets precisely at 36 inches from the finished floor for optimal ergonomics and standard compliance. Make sure the deadbolt throw extends fully and smoothly without any resistance, which may require adjusting the strike plate or adding shims. Proper alignment ensures security and ease of use, so test the mechanism thoroughly before finalizing installation.
Painting or Staining
If the wood is bare, always apply a primer first to ensure better adhesion and a more even finish. Follow with two coats of your chosen finish, making sure to cover all six sides, including edges and ends, for full protection. For exterior projects, select a UV-resistant paint or stain, especially when using dark colors, to prevent fading and damage from sun exposure.
Maintenance Tips
- Lube hinges every spring with silicone spray.
- Check finish yearly; touch up peeling paint ASAP.
- Tighten hardware screws before holiday traffic.
Safety & Code Compliance
The 2021 IRC requires exterior doors to meet minimum U-factor ratings and emergency egress clearance (section R311). Pull a permit where applicable; inspectors love seeing manufacturer installation sheets on site.
FAQs
Do I need a permit for installing double exterior doors?
Usually, yes—most municipalities treat exterior openings as structural. Call your local building office first.
Can I reuse my old brick-moulding?
You can, but new casing often covers gaps better and holds paint longer.
What’s the best material for harsh climates?
Fiberglass beats wood for moisture, yet mimics grain beautifully. Steel excels where security trumps dents.
How to Install Double Exterior Doors when the wall is load-bearing?
You’ll need a properly sized header; consult an engineer or pull dimensions from your jurisdiction’s span tables.
Why does my new door leak air at the sill?
Check that the adjustable threshold screws are set snug against the sweeps—minor turns make major differences.
Can I automate my double doors later?
Absolutely. Choose a smart lock with a multipoint kit; retrofit takes under an hour.
