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Standard Smart OH Cowl

Standard OH Cowl

All Standard Cowls feature an easy to use toggled fixing band which is suitable for installation on Chimney Tops which terminate with a standard Flue Liner. No fixings are required as the toggles snap the wide band tightly around the circumference of the terminal and hold the Cowl firmly in place.

Standard Smart OH CowlDesigned to Increase Updraught and Prevents Rain Ingress

Smart H Cowl Stainless Steel Finish

Stainless Steel Finish Smart OH Cowl

Smart H Cowl Cream Finish

Cream Finish Smart OH Cowl

Smart H Cowl Black Finish

Black Finish Smart OH Cowl

Smart H Cowl Terracotta Finish

Terracotta Finish Smart OH Cowl

Standard Smart OH Cowl is suitable for most conventional clay chimney pots with an 8 inch (200mm) internal and 9 inch (230mm) external diameter. H Cowl is designed to prevent foreign bodies entering chimneys, to increase updraught and to prevents rain ingress. Designed for situations where the chimney is too short (conservatories) or where the chimney doesn't clear the ridgeline of the house, OH Cowl is the best Chimney Cowl you can choose for downdrought problems.

This Standard model is designed to be fitted with Integral Toggles over the Flue Liner. Smart OH Cowl is available in 4 finishes which are illustrated above.

How OH Cowl Works

OH Cowl Section

In normal or still air conditions, the hot gases and smoke pass up the chimney and exit out of the top of both of the vertical tubes.

OH Cowl Section

If wind drives downwards in turbulent conditions, the air moving down the tubes increases in velocity because it is restricted as it is forced through a narrow gap as it passes over and around each end of the horizontal tubular section projecting half way into the vertical tubes. The increase in velocity, basically a venturi effect, induces suction as it passes the horizontal tube and the hot gases and smoke exit out of the vertical tubes. Any upward gusts of air will also act in a similar manner, so this design of "OH" cowl becomes very effective in windy conditions where the chimney is subject to "downdraught".


  • »Promote positive updraught;
  • »Fits most conventional chimney pots;
  • »Made from Corrosion proof Stainless Steel;
  • »Durable Construction;
  • »Quick and simple to install;
  • »Prevents rain ingress.

Our Price: €150.00

Sale Price: €144.95

Free Delivery for UK & Ireland

Buy Smart OH-Cowl

DownDraught Explained

DownDraught Explained Part 1
DownDraught Explained Part 2
DownDraught Explained Part 3
DownDraught Explained Part 4
DownDraught Explained Part 5
DownDraught Explained Part 6
DownDraught Explained Part 7
DownDraught Explained Part 8
DownDraught Explained Part 9
DownDraught Explained Part 10
DownDraught Explained Part 11
DownDraught Explained Part 12
DownDraught Explained Part 13
DownDraught Explained Part 14
DownDraught Explained Part 15
DownDraught Explained Part 16
DownDraught Explained Part 17
DownDraught Explained Part 18

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