New soapstone stove 530kg on existing joists

[Fabian W]

Hello,

I would like to install a soapstone stove. A Norsk Kleber Kube 5 weighing 535 kg. The fireplace should be in the left corner. The chimney is on the left. The house has a basement; picture 2 shows the room underneath. My question is how to reinforce the floor. The brick chimney is about 25 cm wider in the basement than in the living room. The seller therefore suggested cutting open the floor, fastening rebar to the chimney's overhang, and pouring concrete. Could this work? Alternatively, could the beams between the chimney and the wall behind be reinforced?

Thanks in advance for any suggestions.

Best regards,
Fabian

 

[tensiden]

Will it be a similar maneuver as when you install a tiled stove, as the seller suggested?

In our house, there were tiled stoves long ago before they were removed. When we installed new ones, iron was inserted into the chimney and then a slab was cast. I think it will be the same for you.

 

[Eld]

You must open either the ceiling in the basement or the floor where it is to stand to see how it looks before it can be assessed if or how it needs to be reinforced.

535 kg should be able to be supported by a floor without reinforcement, but of course, it depends on when and how it is built.

 

[Farstatjej90]

You must open either the ceiling in the basement or the floor where it will stand to see how it looks before you can assess if or how it needs to be reinforced.

535 kg should be manageable for a floor without reinforcement but of course, it depends on when and how it was built.

It's right by the wall, too!

 

[tensiden]

But everywhere I read on the internet right now, it says that about 350-400kg and upwards require reinforcement. Since this also involves building notification, you can't get away with "it should hold."

Expect to take up the floor and place a slab, which is anchored into the chimney breast.

When we did this, it was definitely not the major part of the cost. I also don't remember the time taken since material was being brought in and a lot of other preparations were happening simultaneously, but cutting up the floor, drilling in iron, and pouring the slab were quickly done by those who do it regularly.

Then it will also be fireproof under the stove.

 

[Eld]

A modern house should withstand a point load of at least 500 kg. This is just above that, but on the other hand, it is not exactly a point load. It (reasonably) spreads over several floor joists. Additionally, it is in a corner where the flooring can handle much higher loads than it would in the middle of the room (for which it is designed).

Now, it is not(?) a modern house, so we do not know how well-built the flooring is. What do the supports of the joists look like at the ends? Is it well-constructed or hastily done? What are the dimensions? Are they intact?

 

[Fabian W]

But everywhere I read on the internet right now, it says that about 350-400kg and upwards require reinforcement.
Since this also involves building notification, you can't get away with "it should hold."

Expect to take up the floor and set a slab, which is anchored into the chimney.

When we did this, it was absolutely not the major part of the cost. I also don't remember the time consumed because materials were carried in and a lot of other preparations were being made at the same time, but cutting up the floor, drilling in iron, and casting the slab was quickly done by those who do it regularly.

Then it becomes fireproof under the stove as well.

Thanks, it's good to hear that someone has experience with such a solution. Without experience, it felt a bit strange to distribute the weight "just" on one side (the chimney).

 

[Fabian W]

A modern house should at least withstand a point load of 500 kg. This is just above that, but on the other hand, it's not exactly a point load. It (reasonably) spreads over several floor joists. Additionally, it is in a corner where the joist system can handle much higher loads than it would in the middle of the room (as it's usually designed for).

Now, it's not(?) a modern house, so we don't know how well-constructed the joist system is. How do the joists rest at the ends? Is it well-built or carelessly done? What's the dimension? Are they intact?

The year built is 1908, so not exactly new. But renovated in the 70s (e.g., new chimney), the walls are carpenter's logs resting on lecablock/concrete down to the basement. I'll take some pictures when the floor is open.

 

[tensiden]

Thanks, it's good to hear that someone has experience with such a solution. Without experience, it felt a bit strange to distribute the weight "only" on one side (the chimney).

Here you can read a bit on the topic. A good bit down, there's the model with iron into the chimney.
https://www.kanerva.se/fundament.html

Or here
https://www.linds.nu/fundament/

 

[Fabian W]

Hi,
In case anyone is interested in how it turned out:
We discovered that there was a wall and a large beam under the floor, so it was reinforced only with a frame around it and a plywood board on top.