Clay chimney 'cap' advice

[glenlloyd]

Here's a photo of my existing chimney and you can see that it has a clay half-round cap covering the outlet. This matches the one on the old furnace chimney, the 'tunnel' runs north / south on both.

I'd like to preserve this after the liner install but I'm not sure the new SS cap will fit inside it or whether I even need the SS raincap with this. I will have to remove it to install the new top cover when the liner gets put in but since it's not mortared in place that's not a problem. IIRC this clay cap is 18" long and I don't really remember how far it sits over the real opening but I've never had any water infiltration problems with it in the old firebox. My intention years ago when I first installed it was to also install a woven wire screen .5x.5 to keep birds / bats from getting in but I've never had a problem with either one. I will probably bump this up when installing the top plate for the liner, I had hoped to increase height of the clay cap about 2" above the concrete.

These types of caps were prevalent in the early 20th c although most of the ones I've seen in books are taller than this one. This is 15" ID, 7.5" radius height.

Looking for comments

thx

Steve A

 

[glenlloyd]

really....no one's going to give me any grief on this?

steve

 

[pen]

I really think this is going to be one of those things where you are going to have to make a decision as you are doing it as to whether or not what you want to have happen will work.

Sorry I can't give more advice. As long as no water can get between the SS liner and the tile chimney, then you would be fine (also assuming that your chimney meets all other safety measures).

pen

 

[zzr7ky]

Hi -

I don't think it's that big an issue. A new SS Cap Asm. from the chimney liner company is probably required to meet the chimney system spec ification that it was certified with. However the local officials are not likely to go to this degree of inspection. I added a cap to keep rain out. I also like keeping birds out. If I wanted to keep the look as similar as possible I would probably look at trimming the stainless cap with a cut-off wheel so it would fit inside the clay arch. You may still need to gaurd it in the Spring time to keep nesting birds away ; )

ATB,
<ike

 

[BrotherBart]

If you just want to keep critters out and use the arch, get ya some 3/4" metal mesh. Cut half round pieces to fit each side and attach it to the sides with beads of silicone caulk. You will have to lift that sucker off of there to clean the chimney.

Personally I would put the thing in the garage and use a proper chimney cap.

 

[My Oslo heats my home]

I can relate to both the homeowner and the forum members on this one. My only solution would be this; since we are now able to sweep a chimney (liner) from the bottom up, and assuming this can be done on this future install, I would try to make the finish look as close to what the homeowner wants with the replacing of the half round clay cap (after the liner is installed) and using BB's advice on the stainless mesh cut on the half round and placed on either side. This could satisfy all parties.