Hearth Questions

[CSAW]

1. I see that a hearth should be vented at the rear. Should there also be ventilation in the front or sides to allow air in?

2. In one of the R-Value charts it says a ventilated air space of 1" has an R-value of 1.43. Does that mean that 2" has 2.86? And so on?

3. Trying to figure out how much r-value is gained by increasing the air space 3 or 4 inches over one inch air space.

4. Does r-value only increase if the air spaces are separated?

5. At what distance do you get no more benefit from extra distance?

Please bear with me, I'm still trying to learn.

Thanks

 

[Jags]

Just guessing, but I think you were reading the manual late at night when you were tired (just messing with ya. )

The part about venting - are you referring to a heat shield?? Something between the stove and wall (and side walls if applicable)? If so, those are used to reduce the clearance to combustibles, but not usually a requirement if you follow the clearance to combustible specs without a heat shield.

Please correct me if I am misunderstanding.

Oh, and welcome to the forum.

 

[Delta-T]

CSAW, i think if you put these questions into the context of what you are trying to do it would be easier to help.

 

[CSAW]

Jags, sorry no manual, it's an old stove. I'm not talking about the walls just the bottom. Will probably go with a metal wall shield if I can make it look good. Wondering if there is anything to be gained r-value wise by spacing (airspace) up three or four inches over spacing up just one inch. The diagrams I see just show ventilation at the rear and no other venting for lack of a better word.

Delta, Just trying to understand everything I can about building a hearth up off the floor. The old stove I have sits seven inches off the ground on legs. Non listed as far as I know. Old Defiant copy. Will probably make metal shield for bottom of stove also.

 

[CSAW]

Sorry Duplicate

 

[begreen]

Usually the hearth air space is left unvented, but there is no reason why it couldn't be vented. The wall shield, if required, are what get vented. 1" air space is all that is needed.

It would help to know what documents are being referred to, in order to determine whether they apply here. Or post the diagrams so that we can see what concerns you.

 

[CSAW]

Usually the hearth air space is left unvented, but there is no reason why it couldn't be vented. The wall shield, if required, are what get vented. 1" air space is all that is needed.

It would help to know what documents are being referred to, in order to determine whether they apply here. Or post the diagrams so that we can see what concerns you.

Looking at this these two articles. Didn't realize the hearth didn't need to be vented. Still don't know if one inch of air space offers the same r-value as three or four inches. Only talking about the floor here not the walls.

Thanks

https://www.hearth.com/econtent/index.php/articles/hearth_design

https://www.hearth.com/econtent/index.php/articles/stove_hearth_construction

 

[Jags]

Usually the hearth air space is left unvented, but there is no reason why it couldn't be vented. The wall shield, if required, are what get vented. 1" air space is all that is needed.

It would help to know what documents are being referred to, in order to determine whether they apply here. Or post the diagrams so that we can see what concerns you.

Looking at this these two articles. Didn't realize the hearth didn't need to be vented. Still don't know if one inch of air space offers the same r-value as three or four inches. Only talking about the floor here not the walls.

Thanks

https://www.hearth.com/econtent/index.php/articles/hearth_design

https://www.hearth.com/econtent/index.php/articles/stove_hearth_construction

The increase in R value from 1" air space to 3" of air space will be measured in decimal points (and small ones).

 

[CSAW]

Usually the hearth air space is left unvented, but there is no reason why it couldn't be vented. The wall shield, if required, are what get vented. 1" air space is all that is needed.

It would help to know what documents are being referred to, in order to determine whether they apply here. Or post the diagrams so that we can see what concerns you.

Looking at this these two articles. Didn't realize the hearth didn't need to be vented. Still don't know if one inch of air space offers the same r-value as three or four inches. Only talking about the floor here not the walls.

Thanks

https://www.hearth.com/econtent/index.php/articles/hearth_design

https://www.hearth.com/econtent/index.php/articles/stove_hearth_construction

The increase in R value from 1" air space to 3" of air space will be measured in decimal points (and small ones).

Thanks, that's kinda what I expected.