Chimney Cap

[GrantMcscott]

Hi

I have had a brick work put up for a chimney for my woodburner which I am going to put in a twin wall flue liner.  The issue I have is how do I cap the top and put a chimney pot on it.

 

The issue I have is the whole at the top is 600mm x 400mm and I will be fitting a pot with 150mm diameter so there is nothing for the pot to site on.

 

Will I need to cast a cap on the ground and raise it up and cement it on?  or is there another way to do it?

 

Thanks

[Gone West]

I guess you could use something like this if you use a S/S flue.

 

https://www.riversidesheetmetal.net/chimney-caps/5.html

 

 

[joe90]

I lined a chimney recently and used a plate similar to @Gone West posted above, chimney pot and flue cap (to stop rain) but make sure it’s got a wire cage to stop birdies nesting in your chimney, (ask me how I know ?) , oh and make sure it’s stainless steel, others will rust out in months.

[Gordo]

Why not just fit a Flexi liner with Spyder spacer things and vermiculite backfill to void. Would be a lot cheaper and should last a long time if you use the best quality/grade stainless. Or if you want to use twin wall then use a larger diameter pot to suit. How on earth are you going to provide brackets and support bracket to support the twin wall?

[GrantMcscott]

On 11/12/2021 at 16:48, joe90 said:

I lined a chimney recently and used a plate similar to @Gone West posted above, chimney pot and flue cap (to stop rain) but make sure it’s got a wire cage to stop birdies nesting in your chimney, (ask me how I know ?) , oh and make sure it’s stainless steel, others will rust out in months.

How did you fix the cowl to the liner and plate?

Edited December 12, 2021 by GrantMcscott

[joe90]

35 minutes ago, GrantMcscott said:

How did you fix the cowl to the liner and plate?

The liner is clamped to the plate to support its weight and is left long enough to let the cap slip inside it, the cap is clamped to the pot with three “legs” and a long jubilee clip around the pot.

[GrantMcscott]

15 hours ago, joe90 said:

The liner is clamped to the plate to support its weight and is left long enough to let the cap slip inside it, the cap is clamped to the pot with three “legs” and a long jubilee clip around the pot.

you have a chimney pot on the metal plate?  If so how is the pot secured to the metal?

[joe90]

1 hour ago, GrantMcscott said:

you have a chimney pot on the metal plate?  If so how is the pot secured to the metal?

The plate should be cut to sit on the brickwork but not cover it completely, leave enough brickwork around the edge to take the flaunching (cement/Mortor))to secure the pot.

[GrantMcscott]

10 minutes ago, joe90 said:

The plate should be cut to sit on the brickwork but not cover it completely, leave enough brickwork around the edge to take the flaunching (cement/Mortor))to secure the pot.

Ah ok I thought the top was just metal you are using the metal to support the mortar

[joe90]

1 hour ago, GrantMcscott said:

Ah ok I thought the top was just metal you are using the metal to support the mortar

Yes we used a pot and the flaunching holds the pot and metal plate in place.