Opinions on installing block off plate or not

Matty-b

New Member
Dec 2, 2016
15
Victoria BC
Hi I would appreciate thoughts on whether we should install a block off plate or not.
We have a heritage house (built 1913) with fireplace and an unlined flue. It's an interior chimney, basically in the middle of the house.
We are getting a Jotul F400 with 6" double walled stainless liner (approx 25' up Chimney).
I have read in these posts people recommending using a block off plate. But both installers locally say they don't recommend me getting one. We are on the south of Vancouver Island, so have a reasonably moderate climate. It rarely ever gets super cold.
They say here moisture is more of an issue and not having the block off plate keeps the chimney warmer.
Does this make sense? Should I push to have the block off plate installed? Or go with their recommendation?
Thanks in advance - this is my first woodstove and so it's a decent learning curve. Much appreciate communities like this for info.
 

begreen

Mooderator
Staff member
Nov 18, 2005
81,785
South Puget Sound, WA
Welcome. Unless the stove is going to be far out on the hearth and not in the fireplace I would definitely recommend having a block-off plate installed or DIY. Otherwise a lot of heat from the stove will rise up the chimney and not into the room. If the stove is going to be partially in the fireplace then the block-off plate will help retain this heat where you want it. Moisture should not be an issue at all as long as the chimney is in good shape and there is a properly sealed top plate. In your situation the liner must be insulated so the warming factor will be reduced already by the insulation.

We had the Castine about 10 yrs ago so feel free to ask questions about it as you start the season. For sure you will want to have dry wood. The stove will burn poorly trying to burn damp wood. This can be hard to get because lots of dealers call their wood "seasoned or dry" when it is not. Doug fir dries out pretty quickly if you can get it stacked right away. Ask how long it has been since the wood was split and how it was seasoned.
 

jetsam

Minister of Fire
Dec 12, 2015
4,696
Long Island, NY
youtu.be
not having the block off plate keeps the chimney warmer.
Yes, this is the exact problem the block off plate is meant to avoid. ;)

A warm chimney is good, but Vancouver Island isn't the Florida Keys, and you want your heat heating the inside of the house, not the heating the chimney on the way out.
 

Matty-b

New Member
Dec 2, 2016
15
Victoria BC
Welcome. Unless the stove is going to be far out on the hearth and not in the fireplace I would definitely recommend having a block-off plate installed or DIY. Otherwise a lot of heat from the stove will rise up the chimney and not into the room. If the stove is going to be partially in the fireplace then the block-off plate will help retain this heat where you want it. Moisture should not be an issue at all as long as the chimney is in good shape and there is a properly sealed top plate. In your situation the liner must be insulated so the warming factor will be reduced already by the insulation.

We had the Castine about 10 yrs ago so feel free to ask questions about it as you start the season. For sure you will want to have dry wood. The stove will burn poorly trying to burn damp wood. This can be hard to get because lots of dealers call their wood "seasoned or dry" when it is not. Doug fir dries out pretty quickly if you can get it stacked right away. Ask how long it has been since the wood was split and how it was seasoned.
Thanks for the info, that makes sense. I wonder why they are suggesting we don't install the block off plate then? Have you heard of negatives of having the block off plate?
And how did you like the Castine? I am planning to get a load of wood this week, like you said, they all claim to be selling seasoned wood. But hopefully even if it isn't seasoned as much as they say it is, I still have awhile for it to dry out. Hopefully there is enough time left.
 

Matty-b

New Member
Dec 2, 2016
15
Victoria BC
Yes, this is the exact problem the block off plate is meant to avoid. ;)

A warm chimney is good, but Vancouver Island isn't the Florida Keys, and you want your heat heating the inside of the house, not the heating the chimney on the way out.
Thanks, yes I agree. Our moderate climate is only moderate by Canadian standards. As long as there are no downsides, I would definitely prefer that extra heat to remain inside the house. Especially since we still have the original old single pane glass. So there is huge heat lost through them. I am hoping to get a bunch of storm windows built before winter, which should help a fair bit as well.
 

begreen

Mooderator
Staff member
Nov 18, 2005
81,785
South Puget Sound, WA
There are numerous reasons for a dealer to not want to install a block-off plate, though I'd just be guessing in this case. It's more work and they may want the bid to stay competitive, or they may be sub-contracting the labor, or maybe they have had botched jobs in the past or maybe the salesperson heard bad stories about past jobs?

The Castine is a beautiful stove. Ours had the blue-black enamel finish which we loved. It is an able medium-sized stove that can put out some good heat. It takes a good sized log too. On the downside, the F400 has a shallow firebox which means it must be loaded E/W and one must be careful so that logs don't roll toward the glass. The shallow firebox makes it fussier for draft, especially when rear-vented. Having the liner insulated will help and the keep the horiz. section out of the rear of the stove as short as possible and pointing upward at least 1/4" per ft.. How tall is the chimney?

There is no "hopefully" when buying wood. Ask exactly when the wood was split. If they say it was lying on the ground in log form for a year, then just split, it is not seasoned. Ask how the wood was seasoned and for how long. When the wood is delivered check it out before they unload. Take a few splits off the truck. Are they heavy or not too heavy? If you bang them together do the go thud (wet) or ring with a low note like claves? If you have an axe or a maul, split them open and put the freshly exposed face of the wood up against your cheek. If it feels cool and damp, the wood is not dry in the middle and should be refused if being sold as "seasoned". Stack the wood right away and measure the stacks. It's not uncommon for some cheap dealers to short a load. After it is stacked, cover the top but leave the sides open so that the wind can blow through the stacks.
 

begreen

Mooderator
Staff member
Nov 18, 2005
81,785
South Puget Sound, WA
Thanks, yes I agree. Our moderate climate is only moderate by Canadian standards. As long as there are no downsides, I would definitely prefer that extra heat to remain inside the house. Especially since we still have the original old single pane glass. So there is huge heat lost through them. I am hoping to get a bunch of storm windows built before winter, which should help a fair bit as well.
We are in the same climate zone. How large is the house overall and how large an area are you hoping to heat with the stove? 1 or 2 story? Any cathedral ceilings? Will this be mostly nights and weekends or is the goal to burn 24/7?
 

Matty-b

New Member
Dec 2, 2016
15
Victoria BC
We are in the same climate zone. How large is the house overall and how large an area are you hoping to heat with the stove? 1 or 2 story? Any cathedral ceilings? Will this be mostly nights and weekends or is the goal to burn 24/7?
Wow, thanks for all the tips! I hear people here complaining all the time that they get shorted a lot on the amount of wood they get. And yes, around here 95% of the wood we get will be Fir.
As for how much we will be burning it, I am not 100% sure. Our plan is not to use it 24/7, but to have a fire on the colder days, mornings/evenings etc. We have the oil furnace, but I would prefer to use the wood stove more, especially on the colder days. We are pretty use to wearing a sweater since up to now the house is always cold.
The house is about 1200 square feet on the main level (where the wood stove will be) and also has a full basement which is heated separately. There is also a decent size attic we hope to finish in the future, so if down the road (when we finish that space) some heat drifts up there we won't be upset. The house has 10' ceilings as well. We mainly hope to heat the main living area on this level with the wood stove. We are limited by the size of the fireplace and so originally we were looking at the jotul F100. But then we learned of the short leg kits, so that gave us the space to move up to the F400. I think the F400 is much better suited for our space.
 

begreen

Mooderator
Staff member
Nov 18, 2005
81,785
South Puget Sound, WA
From what you have described the F400 sounds like a good choice. We have a larger space with too much glass and are burning 24/7 and thus moved to a stove about twice the capacity.

How tall is your chimney?
 

Ashful

Minister of Fire
Mar 7, 2012
15,556
Philadelphia
we still have the original old single pane glass. So there is huge heat lost through them. I am hoping to get a bunch of storm windows built before winter, which should help a fair bit as well.
Watching, will comment tonight.
 

Matty-b

New Member
Dec 2, 2016
15
Victoria BC
From what you have described the F400 sounds like a good choice. We have a larger space with too much glass and are burning 24/7 and thus moved to a stove about twice the capacity.

How tall is your chimney?
I am not exactly sure, but I would estimate 25 feet.
So for the Castine or F400 do you think going top or rear vented would make a big difference?
 

begreen

Mooderator
Staff member
Nov 18, 2005
81,785
South Puget Sound, WA
I am not exactly sure, but I would estimate 25 feet.
So for the Castine or F400 do you think going top or rear vented would make a big difference?
25 ft. is good. With an insulated liner it should draft ok while rear vented. Top vent might set it back to far in the fireplace, requiring the blower kit in order to move the heat better.
 

blacktail

Minister of Fire
Sep 18, 2011
1,413
Western WA
I'd wait for an opinion from @bholler about the double walled liner.
 

Matty-b

New Member
Dec 2, 2016
15
Victoria BC
25 ft. is good. With an insulated liner it should draft ok while rear vented. Top vent might set it back to far in the fireplace, requiring the blower kit in order to move the heat better.
Yes, that's what the installer was mentioning. With the rear vent we can have it that bit further out in the room. Although for appearance, we don't want to sticking out to much anyway. Ideally around 10-12" outside the fireplace.
Does more then make a big difference for heat transferring into the room?
 

begreen

Mooderator
Staff member
Nov 18, 2005
81,785
South Puget Sound, WA
Yes, that's what the installer was mentioning. With the rear vent we can have it that bit further out in the room. Although for appearance, we don't want to sticking out to much anyway. Ideally around 10-12" outside the fireplace.
Does more then make a big difference for heat transferring into the room?
Yes, unless it has the blower option, the more it sticks out into the room, the better it will heat.
 

begreen

Mooderator
Staff member
Nov 18, 2005
81,785
South Puget Sound, WA
Why? Is the double walled liner a item of debate or not recommended for some reason? My understanding is I don't have a choice except to go that route.
There are a few options on liners. Double-wall can pucker on the inner liner causing future problems. You can ask for a heavy-duty liner instead of the double-wall. It will cost a bit more, but will last longer.
 

Ashful

Minister of Fire
Mar 7, 2012
15,556
Philadelphia
Watching, will comment on Ashful's comment after he comments. ==c
Crap... worked too late again!

First, it's very cool that you have a heritage house. Third generation, I assume?

On the old windows, don't assume they need to be bad. An old single-pane window, properly sealed and in good working order with a storm window installed, will often be more efficient than any multi-glazed replacement. I have Flir photos to prove it, on my own home, and you can find many examples online.

Of course, installing storms is relatively easy, sealing drafts on the original windows can be a bit more work. Check metal weatherstripping if you have the skills and tools to install it, as the best source. If you don't seal the original window well, Jack Frost will visit your storms every winter morning, but that's sort of fun too.
 
  • Like
Reactions: bholler

bholler

Chimney sweep
Staff member
Jan 14, 2014
20,968
central pa
Why? Is the double walled liner a item of debate or not recommended for some reason? My understanding is I don't have a choice except to go that route.
That depends what is meant by double wall liner. If it is the 2 ply smooth wall crap dont do it. If it is preinsulated that is fine
 
  • Like
Reactions: Ashful

Ashful

Minister of Fire
Mar 7, 2012
15,556
Philadelphia
That depends what is meant by double wall liner. If it is the 2 ply smooth wall crap dont do it. If it is preinsulated that is fine
Yeah, I did that smooth wall stuff on my two chimneys. Sounded good, in theory. Unfortunately, the "professional" installer didn't use a proper appliance adaptor between the stove pipe and liner, but instead just crimped the liner, stuffed it into the pipe and ran pipe screws thru it.

I bought my own appliance adaptors, and corrected both, but the result of those screws he ran thru is my inner smooth wall spiral is un-spiraling a little at the bottom. I'm not sure how it's going to hold up to 20 years of annual sweeping.
 

Matty-b

New Member
Dec 2, 2016
15
Victoria BC
That depends what is meant by double wall liner. If it is the 2 ply smooth wall crap dont do it. If it is preinsulated that is fine
on the quote he has Duravent 6" Double walled stainless insulated liner and elsewhere he specifies a 0 clearance liner. I also remember him saying its a rigid liner.
Is that a good liner system?
 
Last edited:

Matty-b

New Member
Dec 2, 2016
15
Victoria BC
Crap... worked too late again!

First, it's very cool that you have a heritage house. Third generation, I assume?

On the old windows, don't assume they need to be bad. An old single-pane window, properly sealed and in good working order with a storm window installed, will often be more efficient than any multi-glazed replacement. I have Flir photos to prove it, on my own home, and you can find many examples online.

Of course, installing storms is relatively easy, sealing drafts on the original windows can be a bit more work. Check metal weatherstripping if you have the skills and tools to install it, as the best source. If you don't seal the original window well, Jack Frost will visit your storms every winter morning, but that's sort of fun too.
Unfortunately they weren't in good working order when we bought the place. Most were painted shut over the years.
I have been slowing taking them apart and getting them working again one by one. I still have 12 more to do. I got a quote on new windows that matched the current ones, just insulated glass. It was around $30,000 and so I instantly became a huge fan of getting storms instead. haha
 

stovelark

Minister of Fire
Oct 10, 2009
1,499
SE CT
Hi Matty- welcome. The Castine is a nice choice and of course installing a block off plate is a better choice than not. Give her dry wood, run stove top around 400-650 and she should do good by you. Good luck.