Smoke Pencil Draught Detector


FREE delivery on all UK orders over £50!

The Smoke Pencil is a clever little device which emits a plume of glycerin vapour which resembles smoke. It enables you to pinpoint hard-to-detect draughts and air leaks. It can be used for domestic and commercial applications as an effective draught detector.

31 in stock

SKU: SPF001 Category:


Cold air has a knack of sneaking in through the tiniest of gaps, which can be hard to locate. The Smoke Pencil is an ingenious draught detector for pinpointing air leaks and tracking down hard-to-find gaps. When the trigger is pressed, a plume of smoke-like substance is released. This is actually generated from a harmless glycerine-like fluid, giving off a slightly sweet smell. When the trigger is released, the “smoke” stops, making it highly controllable. It’s useful for detecting draughts around the house, but we’ve also sold them to hospitals, mechanics, for detecting leaks in boat hulls, and even to a drama group who wanted an Aladdin’s lamp prop! It comes with an 80ml bottle of fluid (enough for several hours’ worth of draught investigating)

How to use the Smoke Pencil

Insert 6AA batteries into the Smoke Pencil through the bottom battery door
Lay the unit on its side and remove the “fill” plug. nsert the fluid bottle’s long spout far into the tank. Then squeeze in the fluid.
Flip up the lock mechanism on the trigger. Press trigger gently until the LED light glows, indicating the power to the smoke generator is on. Hold for 6 – 9 seconds, after which a plume of smoke will start to be emitted.
Find draughts and air leaks!
Switch it all off when you’ve finished.
A small amount of water will accumulate in the “empty” tank. This can be squeezed out using the fluid bottle and reused. It’s recommended that the fluid tank is emptied after use so it doesn’t leak glycerine stuff out while it’s stored. It’s harmless but a bit sticky.
Here’s a video to show the Smoke Pencil One in action.

Where to use the Smoke Pencil Draught Detector

The Draught Proof Advisory Association lists the range of locations where you should look for draughts. These include:

  • Through letterbox openings
  • Around windows
  • Around or under doors
  • Through keyholes
  • Through holes drilled for pipe work
  • Through electrical fittings in walls and ceilings
  • through plug socket gaps
  • through uninsulated walls
  • through gaps between floorboards
  • through chimneys
  • around loft hatches
  • at ceiling to wall joints
  • through gaps behind beams

a diagram of a house with the locations of all possible air leak locations from which draughts can occur