Sealing drafty exterior doors
If you can see daylight around a closed door or feel a draft, the weatherstripping or door sweep is worn. Replacing them keeps out dust, bugs and hot air, and makes the door close more solidly. Sometimes the door also needs adjusting so it meets the seal evenly.
Rosemead summers are hot, and Santa Ana winds bring dust. Exterior doors in ranch homes, often the front door plus a back or garage door, are major sources of drafts. Worn weatherstripping is one of the cheapest fixes for a more comfortable house.
Why it matters in Rosemead
Rosemead summers are hot, and gaps around doors let cool air out and hot air in. In winter, the same gaps let in drafts and dust. Worn weatherstripping also lets in insects and noise from busy streets. Replacing it is one of the most effective routine repairs for comfort.
Signs of a leaky door
- Daylight visible around the edges or under the door
- A draft you can feel with your hand on a windy day
- Dust or leaves collecting just inside the door
- Ants or other bugs coming in at the threshold
- The door rattles in its frame when closed
Parts of the seal
Jamb weatherstripping runs along the sides and top of the frame. Most modern doors use a foam or rubber strip pressed into a slot.
Door sweep attaches to the bottom of the door and brushes the threshold.
Threshold is the strip on the floor under the door. Some are adjustable in height.
Types of weatherstripping
- Kerf-in seals: slide into a groove in the door frame, common on modern doors
- Foam tape: adhesive foam strips, easy but short-lived
- V-strip: a folded plastic or metal strip that springs open
- Compression bulb: rubber or vinyl bulbs on a wood or metal carrier
- Door sweep: attaches to the bottom of the door
- Threshold seal: a rubber insert in the threshold
Door sweeps and thresholds
The bottom of the door is often the worst gap. A door sweep screwed to the inside bottom face seals against the threshold. Adjustable thresholds have screws that raise the top. Replacing a worn threshold insert can close a gap.
Our steps:
- Remove old weatherstripping and clean the frame
- Measure each side and the top
- Cut and install new weatherstripping
- Adjust the strike so the door closes against the seals
- Install or adjust the sweep and threshold
- Test with the paper test
Door alignment
If the door sags, weatherstripping cannot seal. Tighten hinge screws and add a long screw into the framing at the top hinge. If the latch does not catch, adjust the strike. Doors that rub usually need the hinges adjusted first.
Garage doors
Garage doors have a bottom seal and side seals. Replacing the bottom seal keeps out dust, leaves and pests. For a garage used as a workshop or gym, weatherstripping also helps comfort.
See garage shelving and storage.
Doors between the house and an attached garage deserve a good seal to keep fumes and dust out. They also often need a self-closing hinge, depending on the setup.
Summer comfort
Weatherstripping works with shades, fans and other measures. See our summer heat checklist.
French doors and double doors
Double doors need seals where the two doors meet. An astragal, a vertical strip on one door, covers the gap. Flush bolts at the top and bottom of the inactive door hold it closed.
Weatherstripping between the doors and at the bottom of each door keeps drafts out. These doors are often the leakiest openings in a home.
Sliding glass doors
Sliding doors have pile weatherstripping, fuzzy strips in the frame. It flattens over time. Replacing it, along with worn rollers, makes sliders seal and slide better. Sliders that do not close fully let in dust and insects.
Pet doors and mail slots
Pet doors and mail slots also leak air. Mail slots can be fitted with an interior flap or brush seal.
How long it lasts
Foam tape lasts about a year or two. Vinyl and rubber seals last several years. Silicone bulb seals last longest. Check seals every fall and spring.
Choosing a sweep
Door sweeps come in vinyl, rubber, brush and aluminum-backed styles. Brush sweeps work well on uneven thresholds. Automatic door bottoms drop a seal when the door closes and lift when opened, which works where a sweep would drag on carpet or tile.
Paint and seals
Painting over weatherstripping hardens it and ruins the seal. When painting doors and frames, remove or mask the weatherstripping first, and let paint dry fully before closing the door against it.
A well-sealed door should close with a light push and latch without slamming. If you have to lean on it, the new seal is too thick and should be trimmed or swapped for a thinner profile.
How we seal a drafty door
We check each exterior door, adjust hinges and strikes, replace jamb weatherstripping, install a new sweep and adjust the threshold. We finish by testing the door closes and latches easily. See doors and cabinets.
When you want it done for you, our door and cabinet repair page lists the jobs we take and what to send for a quote. More on the houses themselves: repair notes for postwar Rosemead homes.
Need a hand with this?
Call or text (310) 628-9399, Mon–Sat 8:30 AM–7 PM. A photo is usually enough for a free estimate.
Call or text for a free estimate