Home › Doors & Windows › Swollen Wooden Door

DOOR ALIGNMENT & MOVEMENT

Swollen Wooden Door

A wooden door swells when it absorbs moisture. The lasting fix is to remove the moisture source, let the timber stabilise and then make the smallest adjustment needed.

↔
!

Check the door type before altering it

Fire doors, security doors, glazed doors and external doors may need specialist adjustment. Do not remove excessive timber or disable closers, seals or locking hardware.

MOST LIKELY CAUSES

Start with hinges, gaps and the first contact point

High humidity Timber absorbs moisture from damp air.
Water ingress Leaks or failed exterior coatings wet the door.
Unsealed edges Bare top, bottom or cut edges absorb moisture quickly.
Poor ventilation Moisture remains trapped around the door.
◫ Symptom variations Match the movement, rubbing and closing pattern. ⌄
  • Door sticks after rain
  • Bottom edge feels rough
  • Paint is cracked or peeling
  • Door returns to normal in dry weather
  • Timber looks darker near one edge
✓ Quick checks Simple checks before trimming or moving hardware. ⌄
  1. Identify where the swelling is concentrated.
  2. Look for leaks, failed seals and damaged paint.
  3. Check the top and bottom edges for bare timber.
  4. Measure indoor humidity.
  5. Allow the door to dry before trimming.
Important: Mark the exact cause before making adjustments. Random trimming can create bigger gaps without fixing the real fault.
1 Step 1 — Stop the moisture source Make the smallest safe correction and recheck the door. ⌄

Repair leaks, improve ventilation and protect exposed timber.

2 Step 2 — Let the door stabilise Make the smallest safe correction and recheck the door. ⌄

Avoid trimming while the timber is still wet and expanded.

3 Step 3 — Ease and reseal only if needed Make the smallest safe correction and recheck the door. ⌄

Remove the minimum amount and seal every exposed surface.

⌁ Why the problem happens How hinges, frames, timber and gravity affect the door. ⌄

Timber expands across the grain as moisture content rises. Trimming a wet door too early can leave an excessive gap once it dries.

⌘ Advanced checks Further diagnosis for persistent alignment faults. ⌄
  1. Use a moisture meter if available.
  2. Inspect frame moisture.
  3. Check exterior weather seals.
  4. Review drainage and threshold details.
  5. Check all six door faces are sealed.
◇ Tools and information needed Useful items for accurate checks. ⌄
  • Moisture meter or hygrometer
  • Screwdriver
  • Fine sandpaper or plane
  • Primer or wood sealer
  • Paintbrush
▣ Parts or improvements that may help Common items linked to this problem. ⌄
  • Exterior-grade sealer
  • Primer and paint
  • Weather seals
  • Threshold seal
  • Replacement timber where rot is present
! When to call a professional Conditions that should end basic DIY diagnosis. ⌄
  • The timber is rotten or soft.
  • An external door has major water ingress.
  • The door is a fire door.
  • The frame is also swollen or damaged.
  • The door needs major reshaping or replacement.
? Frequently asked questions Common door alignment questions. ⌄

Should I plane a swollen door immediately?

Usually no. First dry it and fix the moisture source.

Why must the bottom edge be sealed?

Unsealed end grain absorbs moisture very quickly.

Will the door shrink again?

Often yes, once moisture levels return to normal.