Do I need to replace this metal flashing

[troy-pit]

I am going to install class a chimney pipe up through this "chimney". The top is a square metal flashing that does not seem too thick and seems like it would not be able to support too much weight. It is about 64" by 36". Can I run the class a chimney pipe up through this metal flashing. Do I need to replace this flashing. If I do need to replace it where would I go to replace it. What is going to support the weight of the chimney pipe. Does the stove support the weight of the class a pipe. I am very confused at this point.

 

[skinanbones]

With the amount of rust that is there i would replace it. When we have to seal the top of chimney chases like that, we have a HVAC shop make it up in one piece to cover the whole top. Also while your replacing it you can shim the centre so that water will not pool.
As for what supports the weight of the chimney, it all depends on what kind of install your doing and what brand of chimney that your using. More than likely there will be a support at a lower level that takes the weight of the chimney

 

[begreen]

What is this a chimney for? It does not look like high-temp pipe coming out of the top.

 

[troy-pit]

There is nothing coming out of the top. It is just a hole about 14 inches in diameter with a metal ring rising up around the hole of only about 1/2 inch. It is a chimney for a new blaze king alcove installation I am working on. As for what will support the weight of the chimney pipe it is going straight up the alcove to this top metal piece. The roof of the alcove would be the only thing this chimney goes through before it reaches this piece of mental flashing. The alcove roof would be only sheet rock although I could make it with support to support the weight of the chimney. Can the class A just sit on top of the stove and have the stove support the weight of the chimney pipe.
Attached is a picture of the interior of the project so far

 

[begreen]

The alcove roof should be framed so that a ceiling support box can be installed. That is what will support the weight of the chimney. The flashing up top should be replaced if it's rusting through but don't expect it to support the chimney. The stove should then be connected to the ceiling support box with double-wall stove pipe. A telescoping stove pipe will make connection much easier.

 

[skinanbones]

Like what begreen said you need to frame a ceiling, probally easiest at the current header. That then gives you a spot to put the ceiling support box for the chimney, it also allows you to fully insulate the alcove. Than you can run double wall pipe from the stove to the chimney, and just have a short run of chimney from the ceiling to the top of chase.

 

[begreen]

Check the stove alcove clearance requirements carefully. Note the minimum ceiling height requirement too. Often this is 84".

 

[bholler]

Also check the requirements for additional support of the chimney most need additional brackets spaced out along the height of the chimney. Most require one per 8' But that does vary. Basically you need to first confirm all clearances for the stove then pick you chimney and follow all the directions and use the correct parts for that system. And yes replace that rusty chase cover preferably wit ha stainless one.

 

[begreen]

Additionally, if this is a 2 story chase there should be a firebreak at the one story level.

 

[troy-pit]

Well the alcove clearance on top of the blaze king scirocco is 37 inches above the stove so I can put the top of the alcove to cover that easily. I guess I should put one of these (broken link removed to http://www.stoves-pipes.com/ICC-EXCEL-CEILING-SUPPORT-SQUARE-10-X-10-6-I-D-p/icxm6ess.htm) and frame it in with the alcove to provide support for the pipe as well as facilitating going through the roof of the alcove.

This is a 10" x 10" support box. I also see that they make a 12" x 12" one. Not sure why I would get one over the other. Also can I just frame this box with 2 x 4's to support it and the pipe.

Also see that they make a round support box. here: (broken link removed to http://www.stoves-pipes.com/ICC-EXCEL-CEILING-SUPPORT-ROUND-6ERDS-6-I-D-p/icxm6erds.htm)

Seems to look nicer but not sure if the framing would be more difficult with the round one.

Also did not know I would need more supports going up the chimney?

 

[begreen]

Yes, the BK has lower alcove ceiling requirements. Theres no harm in exceeding minimums if possible. Yes, you box frame the opening for the support box then screw the support into the surrounding framing. 2x4s are fine. We have a round support box. It's no bigger deal for installation. Yes, you will need to support the chimney with wall braces per mfg. requirements.