A letterbox is one of the most overlooked draughts in a home. It is a rectangular hole through the door, usually with a flap that no longer closes quite as it used to. Fixing it is straightforward.
Option 1: an internal brush cover
A plate with a brush, screwed to the inside of the door around the opening. The bristles part when the post is pushed through and close again afterwards. It is the fastest, cheapest fix and works with most existing plates. See the letterbox range.
Option 2: a brush and a flap together
Some covers combine a brush with a sprung flap, so there are two layers of seal. This suits older, windy doors.
Option 3: replace the letterplate
If the flap is bent, the spring has gone or the plate rattles, a new draught-proof plate with a telescopic sleeve replaces the whole fitting. Measure the opening, the screw centres and the thickness of the door before ordering.
Option 4: a catcher or cage
A fabric catcher or a metal cage is not a seal, but it catches the post and reduces the amount of air blowing through the slot. It also protects the post from dogs and stops it landing on a wet mat.
How to fit a brush cover
- Remove any existing inside flap if it is in the way.
- Hold the cover over the opening and check that the aperture is no bigger than your own, so the post can pass.
- Mark the screw holes, make small pilot holes and fix the cover.
- Push a letter through to test the brush.
Do not forget the keyhole
An old mortice keyhole is a small hole that can whistle in the wind. A cover plate or a push-fit cap closes it when the key is out.
Fire doors and listed doors
A fire door has special requirements about what can be fitted to it. If your front door is a fire door, check the manufacturer's advice or ask your landlord before fitting anything that needs drilling.