Adjacent to the kitchen is the living room with a fireplace, where we are likely going to install a cassette. There are plans to use the fireplace for more than just ambiance. In the kitchen, I am installing OSB but became a bit unsure about my construction at the chimney.
I have placed 45x95 studs directly against the chimney, and on the studs, I have placed OSB. Therefore, there is a 95 mm air gap between the chimney and the OSB, but the studs are directly against it. The chimney is built with "ordinary" bricks.
Do you think this would be classified as a fire hazard?
I have placed 45x95 studs directly against the chimney, and on the studs, I have placed OSB. Therefore, there is a 95 mm air gap between the chimney and the OSB, but the studs are directly against it. The chimney is built with "ordinary" bricks.
Do you think this would be classified as a fire hazard?
Yep!
You should have at least 50 mm between wooden studs and the outside of the chimney, and at least 250 mm from the inside of the flue to the wooden studs. So, if you have a wooden stud directly opposite the side of the flue, it should be 250 mm from the inside of the flue to the wooden stud, regardless of whether the wall is load-bearing or not. Otherwise, 50 mm. Wood paneling and boards can have direct contact with the plastered side of the chimney (oddly enough, they're just as flammable/easily ignitable).
Switch to metal studs if you are going to have direct contact with the chimney.
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Byggaren
You should have at least 50 mm between wooden studs and the outside of the chimney, and at least 250 mm from the inside of the flue to the wooden studs. So, if you have a wooden stud directly opposite the side of the flue, it should be 250 mm from the inside of the flue to the wooden stud, regardless of whether the wall is load-bearing or not. Otherwise, 50 mm. Wood paneling and boards can have direct contact with the plastered side of the chimney (oddly enough, they're just as flammable/easily ignitable).
Switch to metal studs if you are going to have direct contact with the chimney.
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Byggaren
One more thing, no mounts in the chimney with things like brackets, threaded rod, etc.
/Kent
/Kent
That depends on whether the flue for the fireplace really goes directly towards the kitchen side or if there are pipes used for ventilation air passage in between.
There is no requirement that the entire chimney stack must be free, only around the channel where it gets warm, right?
There is no requirement that the entire chimney stack must be free, only around the channel where it gets warm, right?
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T&H>There's probably only one person who can answer that and that's the current chimney sweep. However, something tells me that most people want the whole chimney free.
/Kent
/Kent
Nope. There is a requirement that the entire chimney stack must be free. Not just where smoke channels exist. This is because the entire chimney stack expands in length when heated. Thus, you are not allowed to place loads on or attach anything to the chimney stack. (Only in certain cases, such as a concrete plate and depending on the heat source's effect. Then even the concrete edge can serve as a wall in the smoke channel.)T&H said:
If there is a ventilation channel closest to the wall, the combustible distance is measured from the inside of the smoke channel.
If you have 120 mm brick as a partition wall and 140 mm as a ventilation channel and 120 as the outer chimney stack wall, then you are fine with 50 mm to the nearest vertical wooden stud. If you have 120 outer chimney stack wall, the vertical wooden stud must not be closer than 300 mm (provided it's not directly in line with the smoke channel), otherwise, it depends on the heat source's effect and the calculated temperature on the outside of the chimney stack (must not exceed +70C) that determines how close you can go. In both cases, a horizontal wooden stud must not connect directly to the chimney stack's outer side. There should be a gap of at least 30 mm.
In both cases, combustible ceiling paneling, wall coverings, and floor coverings can have direct contact with the chimney stack. The most peculiar thing is that you are not allowed to fill the wall with insulation (even if it is non-combustible) between the nearest vertical wooden stud and the chimney stack.
For this reason, 'wings' of brick used to be extended from the chimney stack to which the walls were connected. The wings also served as protection from heating the wall from the heat source in the room, typically a tiled stove or a fireplace. It is still allowed to extend a ledge of half-brick and let a standing stud directly connect to this ledge (which should be plastered along its entire length just like the chimney stack), just not directly in line with the smoke channel.
The rules are so complex that not even the chimney sweeps know them correctly. Those who have the best understanding of what applies are the Swedish Civil Contingencies Agency and, of course, also the National Board of Housing, Building and Planning, which issues the building regulations for this in consultation with the Swedish Civil Contingencies Agency.
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Byggaren
But HELP! I asked the chimney sweep what I could do. What if he was talking nonsense?imported_Byggaren said:
I have thin wooden studs behind the plasterboard and fastened the kitchen fan to the chimney with screw plugs. The chimney sweep said it was no problem as long as I wasn't going to use the flue where the oil burner was used. Then he went around and explained that "here and here you should have space because on that part of the chimney shaft is the smoke path for the stove. On the other side, I don't care what you cover with." It feels very frustrating that you can't trust the pros. Should you get another chimney sweep from a different district for a second opinion?
It's pretty late now, everything has been tiled and finished for a year.
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I also have a bad experience with a chimney sweep in the area where I live. He said that sometimes it's enough to "run around the house to get the air circulating" How the f...k would that look??? Additionally, he did nothing but shine down the chimney with a flashlight and said "just keep burning, because there's no point in pressure testing - it most likely leaks anyway." Really feels safe :eek:
No offense to all you chimney sweeps out there, the others we've had have been great!
How the f...k would that look??? Additionally, he did nothing but shine down the chimney with a flashlight and said "just keep burning, because there's no point in pressure testing - it most likely leaks anyway." Really feels safe :eek:No offense to all you chimney sweeps out there, the others we've had have been great!
Which is fantastic about forums and the internet. Some consider it unnecessary to ask questions online because you still have to ask professionals, which can indeed be wise, but at the same time, it is invaluable to hear others' opinions about how to interpret regulations so you can ask the right questions to chimney sweeps, inspectors, and builders, as apparently these do not always provide correct information.mycke_nu said:
Oh, how wonderful that you are discussing exactly what I'm wondering about too. Although I'm getting even more confused, but still. ;-)
Builder: Do I understand your post correctly that the distances to the nearest wooden stud not only depend on the chimney's dimensions but also on the heat source? What do you do if you have an existing structure around the chimney (which is probably old and built according to completely different regulations) and are going to change the heat source? We are planning to build an interior wall that borders the chimney. Right now, there is no stove in our house, and the chimney is only used as a ventilation channel, but we might want to install a stove sometime in the future, who knows. Our plan is to put up a metal stud directly against the chimney and have the rest of the construction made of wood with plasterboard, but if you want to follow the regulations in case of a possible stove installation later, you should probably check if the construction is okay for that, which in reality becomes a bit absurd because the rest of the walls that border the chimney probably don't meet the standards (where we are going to build the wall, there was also a wall before, and the wooden stud was nailed directly into the chimney). I'm just getting more and more confused...
Builder: Do I understand your post correctly that the distances to the nearest wooden stud not only depend on the chimney's dimensions but also on the heat source? What do you do if you have an existing structure around the chimney (which is probably old and built according to completely different regulations) and are going to change the heat source? We are planning to build an interior wall that borders the chimney. Right now, there is no stove in our house, and the chimney is only used as a ventilation channel, but we might want to install a stove sometime in the future, who knows. Our plan is to put up a metal stud directly against the chimney and have the rest of the construction made of wood with plasterboard, but if you want to follow the regulations in case of a possible stove installation later, you should probably check if the construction is okay for that, which in reality becomes a bit absurd because the rest of the walls that border the chimney probably don't meet the standards (where we are going to build the wall, there was also a wall before, and the wooden stud was nailed directly into the chimney). I'm just getting more and more confused...
It often takes a lot for the chimney sweeps to complain about older existing solutions, but it can happen if the use of the chimney is changed.
I don't attach to the chimney at all, it usually results in a downgrade if done so. I would have installed the stove already and let the chimney sweep pressure test, etc., before closing up the walls. If there's a leak somewhere, it's much easier to fix before the walls, etc., are in the way.
/Kent
I don't attach to the chimney at all, it usually results in a downgrade if done so. I would have installed the stove already and let the chimney sweep pressure test, etc., before closing up the walls. If there's a leak somewhere, it's much easier to fix before the walls, etc., are in the way.
/Kent