Input on chimney chase

[NVHunter]

Ok, here are some plans I drew up for my chimney and chase for my stove install.

What do you guys think? Look okay? Are there any changes or pointers for me?

Thanks

 

[NVHunter]

So does anyone have input for me?

Do I still put a storm collar on the pipe as it exits the chase cap?

Thanks

 

[begreen]

Looks ok, there must be at least 6" pipe extending above the chase top. Yes, a storm collar goes above the chase top cap.

it's #7 here:

 

[NVHunter]

Thanks, I didn't know that. Do I need to put some sort of fire stop in the chase? I have 3.5" of clearance all the way around the pipe so I have the 2" minimum for clearances, just not sure if a fires stop is required somewhere in the chase too.

 

[fossil]

Why not just have an exposed Stainless Class A chimney...why build the chase at all? Rick

 

[bmblank]

Looks

 

[begreen]

I don't think a firestop is required in this case because it starts above the ceiling, but could be wrong. It's best to ask the inspecting authority.

 

[fossil]

That's a pretty tall, slender structure you've drawn. Unless you're an engineer, you'd be wise to have one check this plan out before you go too far with it. (Yes, I are one)

 

[NVHunter]

Home owners association states chimneys MUST maintain a consistent appearance with the rest of the house.

If I had it my way it would just be the stainless steel chimney all the way up...

HOA is a pain to deal with, but that's another whole story and issue...

 

[NVHunter]

The chase from the point where it exits the roof is 68". The required height of the chimney is 74" to meet the 10-3-2 rule for chimney termination.

Do you think 18" square is too slender for that height of a chase?

 

[fossil]

If it's all to be enclosed in a chase, there's really no need to buy the Class A chimney pipe with stainless steel on the outside. It's all stainless on the inside, but it's much less expensive if the outer skin is galvanized. Same ratings, lower price. If you ain't gonna see it, save some $$$.

 

[fossil]

Do you think 18" square is too slender for that height of a chase?

Personally, I don't like the look. But that's not what I'm addressing from a structural standpoint. It needs to be evaluated by a qualified (local) engineer to determine whether or not some sort of lateral bracing is required. Rick

 

[NVHunter]

Yea that's my plan now. I'm gonna just run the galvanized pipe in the chase.

You don't like the look of a chase?

I'll have to get a hold of a local structural engineer I guess.

 

[begreen]

Consider making the chase rectangular, more like 24" or 30" x 18". That way it will look a bit more like a real chimney chase.

 

[fossil]

What we find to be aesthetically pleasing in terms of structural/building elements is, of course, an individual "preference" thing. If you decide to go with the "skinny" chase, I'd strongly urge an engineer's review of the plans. My personal preference (that's just me) would be something like this:

 

[NVHunter]

Ok, that sounds good. 18" x 24" is a good idea.

My plans after I drew this was to run galvanized exterior chimney pipe to save some money. HOAs are a pain to deal with.

I have to submit these plans to an architectural committee so they can approve or deny my plans.

We'll see what they say.

 

[NVHunter]

Would a wider chase be structurally stronger?

 

[Michael Golden]

Why not just have an exposed Stainless Class A chimney...why build the chase at all? Rick

Personally I think they are ugly!

 

[fossil]

Would a wider chase be structurally stronger?

Yes, against lateral forces (wind loads).

 

[NVHunter]

Yea I don't think chases are attractive either but I don't think my HOA would go for a stainless steel pipe sticking 74" up from the roof. So this is my only hope and option.

I think I'll widen the chase as fossil stated to add some more structural support. 24 or 30" now to choose.

 

[NVHunter]

I reworked my drawing for the chase plan on my house. I think a rectangular chase which is 18" X 30" would look better than the slender square one I originally thought of.

Fossil, do you still think I need to have an engineer look at this even with the widening of the chase. I've done the math and put all of the heights and widths in the below drawing. These numbers are exact, as the program I use allows me to type in the exact measurement while drawing the lines and such.

Thanks again for the help and input.