Hi,
I am planning to remove a part (3.5m) of a load-bearing wall and was thinking of using a glulam beam (66x315) supported on 90x90 posts at each end. The column load is calculated to be 22kN using Moelven's calculation program. At one end of the opening stands the chimney, now the carpenter who will help with it all thinks we should embed that end into the chimney instead of using a post there. I have no idea what a chimney can support, is it a good idea or should I insist on placing a post there as well? Aesthetically, it would look much better if we didn't need a post, so from that point of view, the idea is good
/Otto
I am planning to remove a part (3.5m) of a load-bearing wall and was thinking of using a glulam beam (66x315) supported on 90x90 posts at each end. The column load is calculated to be 22kN using Moelven's calculation program. At one end of the opening stands the chimney, now the carpenter who will help with it all thinks we should embed that end into the chimney instead of using a post there. I have no idea what a chimney can support, is it a good idea or should I insist on placing a post there as well? Aesthetically, it would look much better if we didn't need a post, so from that point of view, the idea is good
/Otto
What does the chimney sweep say? Something tells me he/she won't like that solution at all. Some chimney sweeps do not approve of any form of anchoring in the chimney stack.
Personally, I would not recess or attach anything to a chimney stack, whether it is used or not, so that it can be rebuilt without tearing down the house.
/Kent
Personally, I would not recess or attach anything to a chimney stack, whether it is used or not, so that it can be rebuilt without tearing down the house.
/Kent
Agree with the carpentry shop. An acquaintance was forced to cut into their load-bearing laminated beam to make it freestanding from the chimney. This in a several-year-old house where the construction was previously approved.
Ok, so it's not a good idea if one would ever want to make a fire in it (currently it's only used for natural ventilation and as a flue from the kitchen, in that case I assume it would be fine?).
But how should I proceed if I want to have a pillar there then? I had thought of attaching it to the chimney for some form of horizontal support, but that's not possible?
But how should I proceed if I want to have a pillar there then? I had thought of attaching it to the chimney for some form of horizontal support, but that's not possible?
It can be done, but whether that chimney can then be approved for use is another matter.
Additionally, lengthwise wood against a chimney is considerably worse from a fire safety perspective than having end grain against it, so that solution will only lead to more problems the day one wants to use the chimney for burning.
But there must be some way to attach the post?
/Kent
Additionally, lengthwise wood against a chimney is considerably worse from a fire safety perspective than having end grain against it, so that solution will only lead to more problems the day one wants to use the chimney for burning.
But there must be some way to attach the post?
/Kent
What they are usually concerned about is flammable material against it.
You need to check with your chimney sweep what applies there, but I could imagine a couple of sheets of minarit or something similar in between as fire protection.
You need to check with your chimney sweep what applies there, but I could imagine a couple of sheets of minarit or something similar in between as fire protection.
Unfortunately, Minerit does not solve the anchoring problem, but sure.
If the chimney sweep approves the fastening, then it might be a viable path.
However, I don't believe it at all because they are increasingly cracking down on risk constructions.
/Kent
If the chimney sweep approves the fastening, then it might be a viable path.
However, I don't believe it at all because they are increasingly cracking down on risk constructions.
/Kent
The existing wall that I am going to demolish goes from the outer wall to the chimney (and is attached to it), then the chimney acts as a "wall" for a short distance and then it continues with a "real" wall (again attached to the chimney). It's the first part that needs to be removed. So there's really nothing else to attach any form of horizontal support to.
Even if I do the side that is to be removed correctly, will I then have problems with the wall that remains on the other side?
Even if I do the side that is to be removed correctly, will I then have problems with the wall that remains on the other side?
Depending on how the floor structures, etc., look, there are likely alternative routes to take, but let a structural engineer take a look at it. There is quite a bit to consider, to say the least, so you can't get a correct answer here.
If it's also an older house, one should be a bit cautious about the stability of the chimneys. They often stand where they stand, but it's sometimes a bit unwise to rely on them.
Something tells me that a structural engineer will say the same thing, i.e., to do something outside the masonry.
Feel free to let me know how it goes, preferably in a PM, I'm a little curious.
/Kent
If it's also an older house, one should be a bit cautious about the stability of the chimneys. They often stand where they stand, but it's sometimes a bit unwise to rely on them.
Something tells me that a structural engineer will say the same thing, i.e., to do something outside the masonry.
Feel free to let me know how it goes, preferably in a PM, I'm a little curious.
/Kent
What is an older house? This one is built in 1950... is it old enough for me to be worried about the chimney's load-bearing capacity?
I'm in a bit of a mess, the kitchen is demolished and I don't really want to wait out the holiday season to get hold of someone who can come up with better solutions. So either it will be pillars parallel to the chimney or the beam embedded in the chimney (if it holds?). Then I'll take my chances with the chimney sweep and hope he's nice. (And yes, I know I should have planned better, but after a while, you get tired of planning and just have to do something )
I'm in a bit of a mess, the kitchen is demolished and I don't really want to wait out the holiday season to get hold of someone who can come up with better solutions. So either it will be pillars parallel to the chimney or the beam embedded in the chimney (if it holds?). Then I'll take my chances with the chimney sweep and hope he's nice. (And yes, I know I should have planned better, but after a while, you get tired of planning and just have to do something
)I bought a house that had a burning ban, it hadn’t been swept for 5 years. The chimney sweep pointed out that the underarm in the roof truss was too close to the wall. According to him, the distance should be at least 10 cm (longitudinal wood).
You haven't said if the house has an upper floor or a basement, but since it is a load-bearing wall there should be a hearth wall or similar under the floor. Couldn't one anchor a u-beam in that sill/wall and make a hole in the ceiling allowing it to protrude and be anchored in the roof truss or floor joist? The anchoring is done with welded angle iron. You could then place the beam against the wall (possibly filling the cavity with mortar/concrete) and weld on fittings for the glulam beam. The beam can then be painted like the wall and should be able to blend in with it.
You haven't said if the house has an upper floor or a basement, but since it is a load-bearing wall there should be a hearth wall or similar under the floor. Couldn't one anchor a u-beam in that sill/wall and make a hole in the ceiling allowing it to protrude and be anchored in the roof truss or floor joist? The anchoring is done with welded angle iron. You could then place the beam against the wall (possibly filling the cavity with mortar/concrete) and weld on fittings for the glulam beam. The beam can then be painted like the wall and should be able to blend in with it.
ottot>In short...
A chimney is _not_ designed to bear any loads other than its own.
Just because it is made of masonry, you should not assume that it can support the building or parts of the building.
Moreover, they are often built with the softest mortar possible to accommodate movement.
Consult structural engineers or chimney sweeps before you make any mistakes.
By the way, I like JanneL's post, it's a form of solution that does not affect the chimney.
/Kent
A chimney is _not_ designed to bear any loads other than its own.
Just because it is made of masonry, you should not assume that it can support the building or parts of the building.
Moreover, they are often built with the softest mortar possible to accommodate movement.
Consult structural engineers or chimney sweeps before you make any mistakes.
By the way, I like JanneL's post, it's a form of solution that does not affect the chimney.
/Kent
hmm, have been thinking of doing just like Otto now after the vacation. My chimney sweep has thoroughly checked how it looks in my newly furnished attic and that nothing load-bearing is against the chimney breast, so I should probably make a solution that doesn't have supports in the chimney. Either use glulam 100 mm from the wall and some anchoring in the rafter or with a steel beam against the heart wall and in the rafter.
Thanks Kent! Warms a novice
To continue with the U-beam: Is it possible to mount the vertical beam (U or glue-laminated timber) on the top side, as long as it concerns attic space, to avoid having a wall stub in the ceiling on the floor below. The beam can then be attached to the horizontal one at the wall and on a support at the gable. The rafters that have been held up by the load-bearing wall could then be attached/hung in the said beam with some form of hanger iron and bolts. This probably assumes that you have to cut a hole in the gable to insert the beam. In return, you would get a completely smooth ceiling in the open area you made.
Crazy? or?
To continue with the U-beam: Is it possible to mount the vertical beam (U or glue-laminated timber) on the top side, as long as it concerns attic space, to avoid having a wall stub in the ceiling on the floor below. The beam can then be attached to the horizontal one at the wall and on a support at the gable. The rafters that have been held up by the load-bearing wall could then be attached/hung in the said beam with some form of hanger iron and bolts. This probably assumes that you have to cut a hole in the gable to insert the beam. In return, you would get a completely smooth ceiling in the open area you made.
Crazy? or?