masonry chimney with? A B C?

banana · 26 Apr 2006 at 9:51 AM

or to use some kind of board like gypsum, what is such a board called? that you can put against a chimney breast, that is to say, frame with steel studs.

I will have a completely freestanding chimney breast that is 3-channel with dimensions W 1340 x D 360
in a single-story house, I think it feels a bit flimsy and want to make the depth a bit larger.

LyckeKonsult · 26 Apr 2006 at 5:10 PM

I don't know if that's the answer to the question, but bricklaying and plastering (10mm) the chimney under the outer roof with C-mortar and above the outer roof bricklaying with B-mortar and plastering with B+C or C+C (10mm application of each). Above the outer roof, the brick should be primed thinly with A-mortar...
Was that the answer to the question?
If you want to enlarge the chimney, you can brick it up with 7cm leca or lightweight concrete blocks to the shape you want.
e.g.:
http://www.hhcelcon.se/

banana · 26 Apr 2006 at 7:06 PM

Yep Lycke, it was the thing about C bruk indoors I wanted to know,
just go ahead then... thanks!

banana · 28 Apr 2006 at 7:03 AM

LyckeK said:
I do not know if that answers the question, but masonry and plaster (10mm) the chimney under the outer roof with C mortar and above the outer roof, masonry with B mortar and plaster with B+C or C+C (10mm layer of each). Above the outer roof, the bricks should be primed thinly with A mortar...
Was that the answer to the question?
If you want to enlarge the chimney, you can build up with 7cm leca or lightweight concrete blocks to the shape you want.
e.g.:
[link]

a small follow-up question......
when I've removed old plaster and such, should I prime the stock with something to make the mortar adhere better...? some kind of primer or so, the stock is about 100 years old, and the plaster that is on today adheres poorly, so should I reinforce with mesh or is there a good primer?

cpalm · 28 Apr 2006 at 8:21 AM

banana said:
when I have removed old plaster etc., should I prime the log with something to make the mortar adhere better... ? some kind of primer or so, the log is about 100 years old, and the plaster currently on it adheres poorly, so should I reinforce with mesh or is there
a good primer?

No, the plaster probably adhered well from the beginning but eventually "wears out" due to movements in the structure. Just make sure to remove the old plaster thoroughly and then water generously. Reinforcement is only necessary at material transitions and on certain substrates.

LyckeKonsult · 28 Apr 2006 at 9:45 AM

Oh oh oh - there you see how important it is to provide as much info as possible!!!
In your original question, it sounded like you were going to build new!
Your chimney is brick-built and plastered with lime mortar!!!
That means you should clean it thoroughly as "cpalm" writes...
Water it!!!... Prime thinly with Hydraulic Lime Primer (about 5kg/sqm), if you have cracks or visible movements you should use welded render mesh and then plaster 10-15mm (20-25kg/sqm) with Hydraulic Lime Mortar.
(serpo 109 or serpo 148 from maxit)

banana · 28 Apr 2006 at 12:15 PM

LyckeK said:
Oh dear - it shows how important it is to provide as much information as possible!!!
In your original question, it sounded like you were going to build new!
Your chimney is built and plastered with lime mortar!!!
That means you should clean it properly as "cpalm" writes...
Water it!!!... Prime thinly with Hydraulic Lime Primer (about 5kg/sqm), if you have cracks or visible movements you should mesh with welded plaster mesh and then plaster 10-15mm (20-25kg/sqm) with Hydraulic Lime Mortar.
(serpo 109 or serpo 148 from maxit)

yes, it is easy to misphrase oneself, it is more obvious to me when you are in the thick of it

indeed, it is an existing chimney that I want to tidy up and smooth out,
can I then use Hydraulic Lime Mortar for that AND then "tile" with fake brick?
it is as mentioned uneven and irregular, that's why I want to plaster it first

LyckeKonsult · 2 May 2006 at 10:30 PM

Hello, hey...stop now... ;D do you have a ONE HUNDRED YEAR old chimney that you want to put faux brick on!!! :'( It is incredibly beautiful as it is... and it's an old house!

I wouldn't put faux brick on a hydraulic lime mortar... the adhesive you use to set the brick is probably too strong, and you risk it coming loose. Plaster as evenly as you find suitable and paint with a silicate paint... Good luck!

banana · 3 May 2006 at 7:24 AM

LyckeK said:
Hello, stop now... ;D do you have a ONE HUNDRED YEAR old chimney that you want to put fake brick on!!! :'( It's incredibly beautiful as it is... and it's an old house!
I would not put fake brick on a hydraulic lime mortar... the fix you set the brick with is probably too strong, and you risk it coming off.
Smooth as evenly as you think is appropriate and paint with a silicate paint...
Good luck!

Unfortunately, those who built it were probably slightly tipsy under the feet :'(
the brick is all over the place, diagonal, upright, sideways, I mean, dear god!!
so I was thinking of putting fake, but you say it's not appropriate, damn it!!! :'( are there
any other good suggestions?

cpalm · 3 May 2006 at 8:01 AM

banana said:
it is unfortunately the case that those who built it were probably a bit tipsy :'(
the bricks are laid crosswise, diagonally, on edge, on the side, oh my goodness!!

That's how an old chimney looks, there are channels inside.
Smooth it out so it becomes even and nice.

LyckeKonsult · 3 May 2006 at 11:03 AM

banana said:
unfortunately, it's the case that those who did the masonry were probably a little bit tipsy :'(
the bricks are in all directions, diagonally, on edge, on the side, oh my goodness!!
so I thought about faking it, but you say it's not suitable, darn it!!! :'( are there any
other good suggestions?

Imagine if you could show it to people... they would stand and ponder for a long time... but the chimney needs to be plastered on the inside so that's not possible...
You have such large irregularities in the chimney that locally the layers will become so thick that I don't recommend anything else... if you could apply a maximum of 10mm, maybe you could move over to C-bruk.
Ask the chimney sweep about building a new shell around the existing chimney, you might be able to get a 60mm thick cladding brick, so it doesn't add too much... but you have to arrange supports for the cladding... what do you think about that?

banana · 3 May 2006 at 3:42 PM

Ask the chimney sweep about building a new shell around the existing chimney, you might be able to get hold of a 60mm thick cladding brick, so it doesn't build out too much... but you need to arrange support for the cladding... what do you think about that?

[/quote]

My uncle, who used to live in this house, is a chimney sweep, and he thought it was a really weird chimney now that he saw it... :-/
There is support for a new brickwork in one direction, the side that looks the worst, since there used to be a brick wall there, but I have torn it down because it wasn't "anchored" to the chimney, it leaked between the wall and the chimney, so to speak, you could just put a crowbar in between to then topple the whole wall, lucky I did it now so it didn't fall down when the kitchen is finished

Anyway, he thought I should plaster the wall somewhat, and if I then want faux brick, I can frame up and then set minarit...? is that what it's called? and brick there. Sounds pretty convenient, what do you think about that?
It's only in one direction that the chimney is bad/ugly.

LyckeKonsult · 9 May 2006 at 12:51 AM

Putting faux bricks on minerit is totally fine with me...

the question is just if you can do it on one side... how will the connection at the corner look???
And the chimney sweep has probably told you that you must have at least 50mm between the minerit and the chimney breast (I think it is)

banana · 10 May 2006 at 4:34 PM

if I would like to extend the chimney with Leca 7mm, do you cement them in place? you shouldn't have any other kind of fastening in the chimney.

or are there good alternatives?

LyckeKonsult · 10 May 2006 at 5:24 PM

Brick the freestanding but clamp against the flue, and you should have 7cm... or?