Newbie Questions

[Hizelks]

I'm trying to learn as much as I can before I install my wood burning stove in this winter. Curious about some things that I can't seem to find answers to.

I'm I am going to build up a hearth on the cement basement about 3-4 inches can I make up a base with:
1. wood 2x4s, cement board and slate
2. cement pour the slate or
3. sandwich cement board

The current chimney was only used by the previous owner with a wood burner. The flue opening is clay lined 7.25in square. Is it even worth my time trying to get a wrapped 6" liner down it? Is 5.5" liner acceptable? Or should I scrap the idea and just run new pipe elsewhere?

There are obvious codes about chimney heights and restrictions. The one thing I can't find is do inspectors consider an existing chimney as part of the distance (or part of the building) if I were to run new pipe a few feet away from an existing not used chimney? Or should I run the pipe within a few feet and then remove chimney brick to lower it's height since it's not in use? I want the stove to be in a similar spot as the previous chimney so I might need some diagonals to get some distance away from the current chimney.

Sorry, these questions are probably pretty basic and maybe not very clear.
I attached a pic of the wall opening.

Thanks for an responses though

 

[begreen]

Welcome. What stove will this be for? That may affect hearth design. In the least you'll want a sheet of 3/4" plywood under the cement board for stiffness.

 

[Hizelks]

Welcome. What stove will this be for? That may affect hearth design. In the least you'll want a sheet of 3/4" plywood under the cement board for stiffness.

Wood burning stove. I have a Pleasant Hearth 2200

 

[begreen]

According to the manual:
Unit must be placed on a noncombustible floor protection equivalent to 1” millboard. Floor protector must have min. R value of 1.19. Consult your local building authorities for further information.

A single sheet of Durock NexGen cement board is R=.39. It would take 3 layers to come close to the required insulation value for the hearth. Stagger the seams between layers.

 

[Simonkenton]

You are going to put the stove on a concrete floor. You don't need to build a hearth the concrete floor will work fine.

 

[begreen]

Yep, that would save a lot expense and build up.

 

[Hizelks]

I just want it built up so there is a visual barrier. Maybe it will help keep the kids away. Anyone have any opinions or experience with trying to get a 6 inch liner down a 7.25 inch flue?

 

[NaturalCauses]

Is it 7.25 internal diameter? A 6" flex liner has an outer diameter of ~6.25", and if you add about 1.5" for the insulation, you are looking at around 7.75" total outer diameter of the new liner.

 

[Hizelks]

Yes it's a 7.25" inside diameter opening. Should I stay away from 5.5"?

 

[NaturalCauses]

You would want to ask the manufacturer on that.

 

[begreen]

A 5.5" might work. That would come out at around 6.75" OD. Still snug. How tall is the chimney?

 

[Hizelks]

The chimney is about 25'. Is renting a tile breaker tool a fairly simple task? I'm pretty handy and wouldn't mind the project. I assume that would open up plenty of room or a insulated liner. Also the chimney runs down the wall in the garage and is all cinder block. Is that common? Would a liner work with cinder block?

 

[begreen]

Chimney in garage is not uncommon. Haven't heard of a tile breaker being for rent and have never personally done it. Best to have a sweep answer that question.