A door that lets the air in can spoil the comfort of a whole room, and in winter the problem is even more noticeable. Most of the time the answer is simple and cheap: a well chosen draft excluder and a door that closes properly.
Why does air come in under the doors?
The gap between a door and the floor can let cold air in or let warm air out. This affects comfort, especially in exterior doors that lead to the street, a garage or an area that is not heated.
Before you fit any accessory, check whether the draft really comes from that gap and whether the door needs adjusting.
1. Find out where the air comes in
Look at the space under the door and along the sides of the frame. Check whether the seals are worn, whether the gaps are uneven or whether the door does not latch properly.
Do not use a flame to find the drafts. If you need to check the movement of the air, use a safe method that generates no heat and no risk of fire.
2. Fit a bottom draft excluder
Brush, rubber or flexible material excluders can reduce the draft under the door.
Measure the width of the door and the gap with the floor before you buy the accessory. Check that it does not make the door hard to open or rub excessively.
3. Use a movable door sweep
The guards that are placed against the bottom of the door can be a simple solution for certain interior or exterior doors.
They are useful when they can be removed easily, but they do not replace permanent sealing if the door needs a repair.
4. Check the side seals
If the air comes in through the sides or the top, you may need to fit seals that are compatible with the frame.
Do not cover ventilation openings and do not alter safety or evacuation systems.
5. Check how the door closes
A warped door, loose hinges or a badly fitted frame can leave gaps that are hard to fix with a draft excluder alone.
If you notice structural damage or closing problems, consider a repair before adding accessories.
6. Take the ventilation into account
Not every gap should be sealed. Some interior doors may need a gap underneath so that air can move around a home that was designed with ventilation in mind.
Before you change that space, check the ventilation needs of the home, especially if you have combustion appliances or an extraction system.
7. Compare the cost and the durability
Adhesive accessories are usually cheap, but how long they last depends on the surface, the installation and the use. A sturdier product can work out better in the long run if the door is opened many times a day.
Measure before you buy and follow the manufacturer’s instructions.
Conclusion
To reduce the drafts, identify where the air comes in first and choose an excluder that suits the door. Do not block the ventilation you need and do not compromise the closing or the safety of the door. If the problem is a badly adjusted door, repairing the frame can be the most effective solution.
The same gaps, when they are in the windows, are fixed in a different way: in how to insulate windows against the cold without doing any work we explain how to find and seal the places where the heat escapes, and in what temperature to set the heating to save money we look at how to adjust the thermostat when the room is still cold. If you also notice condensation or mold, take a look at why damp appears in the home and how to prevent it.
