Looking for Guidance on Buck 74ZC in Prefab box install

[acottrell]

Hi All,

Looking to get a little guidance on the best way to proceed with pulling out my Superior RD 3800A wood fireplace and replacing it with the Buck 74ZC I bought for my prefab box.

I have already bought the stove and it's waiting at the hardware store for pickup and I have already measured to make sure it will fit in the box.

Right now I am at the point of having pulling off the tile/drywall around the sides and top of the existing box but looks like now I will have to most likely pull off my mantel surround from the wall and also get the tile in front of it on the floor up as well. Then I should have full access to the bottom of the existing pipe to disconnect it and remove it and the stove.

From there, I know I have approximately 26' of chimney pipe that will need to be installed. Would it be easier to try to lock the sections together and lower from the top or work from the bottom up? Currently I am looking at the Selkirk Class A 6" pipe as the hardware store that sold me my stove carries it and I figure buying it local would be a bit more in cost but hopefully more convenient if issues were to arise. Talking with the local chimney guy in my small area, he said it might involve pulling the vinyl siding off the chimney box to install but I wasn't sure. The chimney should be a straight shot up from the stove as it's just a prefabbed chase on the outside of the house going straight up to the top cap.

At this point I'm almost wondering if I got myself in over my head and should look at returning the stove with whatever stocking fee it might be and re-drywall/tile the current fireplace. Am I at that point or am I making this out to be more than it is? The local installer I mentioned earlier said they are way too busy to install anything right now and wouldn't be able to consider it until Feb/March.

Thank you.

 

[bfast250]

I am not a pro. I recently replaced my non-epa fireplace with an epa high efficiency fireplace. I did a full demo and I cannot imagine doing it without a full demo. The only exception might be if you can remove the old fp and install the new from the rear. Is that an option in your situation?

My chase was much shorter. I agree with your friend that removing the siding is going to be your best bet. I don't believe you will be able to lift 26' of class A by trying to install from the bottom.

 

[acottrell]

Update on this:

The current fireplace is out along with all the old chimney piping. My class A liner is on order and will be arriving on Wednesday. Right now I am looking at a few things as I am needing to figure out if I need new firestop inserts as the old ones are for a 10" pipe (that is what the outer pipe of my old liner was) or if I can just run the pipe straight up to the rain cap and call it good leaving that free 1" on each side of it. I have two firestops in my 23 feet of chimney and it would be a bit hard to get to them to install these new firestops but it could be done.

As for the new liner, the current plan is that the chimney will be assembled from below and pushed up as it's a total of 110 lbs. I planned to build it about 12" short as I can add the last section from the top. So raise it up, hold it from the top with 1-2 guys, slide in the stove from the bottom with 1-2 guys, and then lower it down into the stove and connect the final piece on top.

Thoughts?

 

[BenTN]

I agree with your local guy and bfast. 110lbs is alot of weight for a smooth pipe that really has no easy way to grip. You will be in awkward positions on both ends which increases the risks, you or helper injury or damaging expensive class a pipe or stove. I would remove the siding and sheeting in the areas where the firestops are and replace those with the appropriate stops for your pipe diameter and use these access points to assemble the new chimney pipe, sections at a time.

 

[bholler]

I have alaways just climbed down into the chase to do work like that.

 

[acottrell]

That's another option as well as I'm working in the prefab box that's about 2.5' by 4' is to get into the chase, have the stove put in behind me and climb up. Replace the firestops and the plywood holding them as I climb up and have the pipes lowered down to assemble it as I go up.

 

[begreen]

Wondering if a reducer plate could be cut out of 24 ga steel that fits in the existing firestop, but with an 8" hole for the new chimney pipe? This could be pop riveted or screwed in place to make it permanent.

 

[bfast250]

I have alaways just climbed down into the chase to do work like that.

I was able to climb down in my chase for the top two 4 foot sections. The difficult part for me was tightening the locking bands. The first two sections I installed from the bottom up. It was a bit tricky getting the locking band through the firestop, but not the end of the world.

 

[acottrell]

Got more into the chimney today and pulled out the first firestop about 6 feet above where the old unit was. It was just plywood with the metal ring collar in it for the pipe to go through. Going to replace it with 5/8 fire resistant drywall for sure with new a new firestop collar.

There is second firestop about 10 more feet above that one. Do I need to replace this one as well with drywall instead of the plywood? The first was just nailed in from one side, this second appears to be a sheet of plywood on top with a split sheet nailed in from the bottom as well making it much more difficult to remove than the previous one. I will be replacing the firestop insert in it with one for the new class A liner, but just wasn't sure if it was really necessary to replace the plywood with drywall as well for this second one being it's much further up the chase.

Thoughts?

 

[begreen]

Going to replace it with 5/8 fire resistant drywall for sure with new a new firestop collar.

Not following this plan, why drywall?

 

[bholler]

Got more into the chimney today and pulled out the first firestop about 6 feet above where the old unit was. It was just plywood with the metal ring collar in it for the pipe to go through. Going to replace it with 5/8 fire resistant drywall for sure with new a new firestop collar.

There is second firestop about 10 more feet above that one. Do I need to replace this one as well with drywall instead of the plywood? The first was just nailed in from one side, this second appears to be a sheet of plywood on top with a split sheet nailed in from the bottom as well making it much more difficult to remove than the previous one. I will be replacing the firestop insert in it with one for the new class A liner, but just wasn't sure if it was really necessary to replace the plywood with drywall as well for this second one being it's much further up the chase.

Thoughts?

Plywood is a better option in this application.

 

[acottrell]

Plywood is a better option in this application.

Why would this be? Looking at the install manual for my stove it says to "use fire code sheet rock" in the illustration for the firestop and Buck also said this when I called to talk it over with them. So replace the bottom one with sheet rock and leave the second plywood I guess..?

 

[bholler]

Why would this be? Looking at the install manual for my stove it says to "use fire code sheet rock" in the illustration for the firestop and Buck also said this when I called to talk it over with them. So replace the bottom one with sheet rock and leave the second plywood I guess..?

Because if you ever get moisture in there which is pretty common in a chase that drywall will disintegrate and you will never know it.

 

[begreen]

Yes, I'd want to have something more solid and moisture resistant. Cement board maybe, but not drywall.

 

[acottrell]

Alright, well thanks for the input. I'll look at possibly a layer of drywall with the layer of plywood. Just really looking to not have heating issues with the chimney as it's the first ever install for me and there is a bit of nervousness about making sure it's done correctly. I certainly appreciate all the help.

 

[acottrell]

Update:

The stove is in and burning right now! Install went awesome. Six hours of work with two buddies and everything was together to get it fired up. Last bit for tomorrow is to install the new chase cover that will be finished tomorrow along with the pipe cap. For now the old chase cover and just leaving the pipe uncapped tonight as the weather is good and will be warm tomorrow. Until then just enjoying the fire, heat, and the stink of paint curing from the stove.

As for the install, we got the chase opened all up and dropped a climbing rope down that was anchored to a tree in the yard. I got into the chase from the bottom along with the first two pipe sections and the firestop wedged to the side above. I got up and out of the way while my buddy slid the stove in place. From there, started building the chimney out of the duravent pipes that just twisted together to lock. With the climbing rope I had my climbing harness on along with two rope ascenders set up and pulled myself up the rope as need to keep stacking pipes up after installing the firestop. Eventually got to the top and have everything good to go besides the new chase cover and pipe cap so it was time to build a small fire and check for leaks. That went well with great draft and zero leaks so the fire was built bigger to crank it up and cure the paint.

Last steps will be pulling the whole mantle setup off, get the dry wall around the stove repaired and setup for tile. Currently thinking the 3d rock that gets put on with mortar would be nice if we cant find a tile we like and looking to get a nice mantle milled locally from a big cedar my buddy has on his 40 acres.

Thanks for the comments and all the help.