I have ordered an insert like this:
Including legs and a sheet metal chimney. It works fine as it is (without encasing), but it's not very attractive. The idea is to encase it to achieve a result that looks something like this:
The question then is how to do this best. The insert is water-jacketed and therefore kept relatively cool. Both the sides and top are double-jacketed and should stay under 100 °C. But to be safe, it feels right to choose something non-combustible.
I've been advised to either use calcium silicate boards or lightweight concrete (ytong, lättklinker, siporex...).
Calcium silicate boards seem quite simple:
However, I'm a bit skeptical that it feels solid and not like a styrofoam box. The material weighs only 250 kg/m^3 and is 3 or 5 cm thick. It's also not particularly cheap (800-1000 kr/m^2).
Lightweight concrete comes in handy slabs 40x60 cm (5, 7.5, or 10 cm thick):
The 75 mm thick slabs cost about 300 kr/m^2. But the question then is how to deal with the bridging (orange).
The green is then built with the blocks above, and the orange needs to bear some load, after which the blue can be built with the blocks again.
I have two options where I'm not sure which is best.
Option 1: Cast a shift with reinforcement
Build a mold and fill the bottom with reinforcement. To keep the weight manageable, I thought of using expanded clay pebbles as ballast.
Option 2: Build a frame of lightweight concrete beams
It is possible to buy reinforced lightweight concrete beams:
If you cut these to the right length (certainly a bit tricky) and bolt them together with sturdy screws (and mortar between), you should be able to make a frame like this:
The question is which of these solutions is best. Or is there another option?
/Anton
Including legs and a sheet metal chimney. It works fine as it is (without encasing), but it's not very attractive. The idea is to encase it to achieve a result that looks something like this:
The question then is how to do this best. The insert is water-jacketed and therefore kept relatively cool. Both the sides and top are double-jacketed and should stay under 100 °C. But to be safe, it feels right to choose something non-combustible.
I've been advised to either use calcium silicate boards or lightweight concrete (ytong, lättklinker, siporex...).
Calcium silicate boards seem quite simple:
However, I'm a bit skeptical that it feels solid and not like a styrofoam box. The material weighs only 250 kg/m^3 and is 3 or 5 cm thick. It's also not particularly cheap (800-1000 kr/m^2).
Lightweight concrete comes in handy slabs 40x60 cm (5, 7.5, or 10 cm thick):
The 75 mm thick slabs cost about 300 kr/m^2. But the question then is how to deal with the bridging (orange).
The green is then built with the blocks above, and the orange needs to bear some load, after which the blue can be built with the blocks again.
I have two options where I'm not sure which is best.
Option 1: Cast a shift with reinforcement
Build a mold and fill the bottom with reinforcement. To keep the weight manageable, I thought of using expanded clay pebbles as ballast.
Option 2: Build a frame of lightweight concrete beams
It is possible to buy reinforced lightweight concrete beams:
If you cut these to the right length (certainly a bit tricky) and bolt them together with sturdy screws (and mortar between), you should be able to make a frame like this:
The question is which of these solutions is best. Or is there another option?
/Anton
I personally believe more in casting; it should be better from a structural standpoint. What kind of concrete should one invest in? Is regular fine concrete sufficient? It should handle temperatures around 100 °C without issue, right?
A layer of reinforcement on top is probably also a good idea, I just realized. Otherwise, there's a risk of the concrete cracking at the setup.
/Anton
A layer of reinforcement on top is probably also a good idea, I just realized. Otherwise, there's a risk of the concrete cracking at the setup.
/Anton