There were many opinions here. I completely agree that it's better to insulate the entire building for winter and then lower the temperature where room temperature isn't needed. But also remember that warm room air contains more moisture that can condense. In a pinch, you might consider getting through the bathroom to reach a storage room, but if the storage room is later to have an expanded function, it becomes quite hopeless. The best solution then is to create a corridor from which you can access all areas. Think it through carefully first. Bathrooms are expensive to move. Concrete must be edge-insulated to avoid thermal bridges but also to prevent room moisture from condensing in the concrete. Feel free to consult a local architect when you are finished with your drawings.
You could probably say, after all, that if the building hadn't already had a masonry shell, I would have only built the bathroom and no cold storage at all since it's not really needed. But now I do have a masonry shell, and it feels really silly not to use the leftover space for something.
Then it might be that I will rent it out, and I want to keep the heating costs as low as possible.
If, after all, one would want to install a window, how would you do this in the inner wall/air gap, etc.? I'm thinking about having the window facing the patio, where there is no shaft in the wall, just an inner wall, air gap, and outer wall.
Then it might be that I will rent it out, and I want to keep the heating costs as low as possible.
If, after all, one would want to install a window, how would you do this in the inner wall/air gap, etc.? I'm thinking about having the window facing the patio, where there is no shaft in the wall, just an inner wall, air gap, and outer wall.
Much work and cost to create a window in a solid brick wall if you're not skilled in masonry. A lintel must also be installed above the opening. The window should be placed in the opening in the brick wall. On the inside, a frame construction is built that extends to the brick and has the same dimensions as the opening in the brick. The window should be custom-ordered. I would aim to convert the entire outbuilding into a bathroom and use the existing window opening. 18 sqm is not too much for a bathroom that includes a toilet, laundry, shower and bath, towel storage, etc. Maybe even a washing machine. I personally have one that is 20 sqm and it could be larger.
It is an idea to convert the entire space into a larger bathroom/laundry room and actually skip the window altogether. As mentioned, it is largely about the fact that I will probably rent it out from time to time and I won't get any extra rent for a large bathroom. However, the heating cost will be higher... But maybe, after all, it's marginal...
Heating costs are certainly a marginal factor. Regardless of how you intend to use your house, you should think long-term, both in terms of use/functionality and choice of materials. A properly executed bathroom can have a lifespan of 50 years. An incorrect one, at most 10 years. Quality is primarily not a matter of cost but rather a result of the right attitude towards material choice.
Ok, you mean like lecawalls instead of plasterboard, etc.?
Yes, for example. Many people install tiles, a material that can last for 1000 years, on a moisture-insulated stud wall where the moisture insulation only lasts for 10 years. Generally: it's better to plan carefully from the beginning than to have to redo repeatedly.
How would an inner wall of leca be constructed with insulation, etc.?
The lightweight concrete block (lecasten) is built from the existing concrete slab inside the brick wall without an air gap but with appropriate insulation material against the brick. The thickness of the insulation material and the width of the lightweight concrete block should be determined based on the desired insulation standard. The insulation material can be polystyrene or mineral wool, e.g., Rockwool Skalmursskiva. Assume that the brick wall corresponds to 2.5 cm of mineral wool and that the lightweight concrete block has twice the U-value compared to mineral wool. New building standard is 30 cm of mineral wool, which does not seem reasonable in this case. The new concrete slab is cast against the lightweight concrete block. The lightweight concrete block is plastered on the inside.
Okay, then the tiles are glued directly onto the plaster? Surely there must be a waterproof layer in between?
Behind all the tiles exposed to water, i.e., behind showers, bathtubs, washbasins, there must be a waterproof layer. Not otherwise. If you have a shower cabin, no waterproof layer is needed. Around bathtubs and washbasins, you can also use metal or glass outside the tiles.
Hmm, do I have to use a cavity wall insulation board or is regular mineral wool or rock wool okay?
How does the connection between the Leca interior wall and the ceiling work, do you place a beam as a wall plate on top of the Leca?
How does the connection between the Leca interior wall and the ceiling work, do you place a beam as a wall plate on top of the Leca?
How is the attachment of the "hammarbandet" that I need to place on the brick exterior wall done?
It probably works with other variants of mineral wool, but not glass wool. Cavity wall board or ground board is probably best. You need to check its hygroscopic properties. The higher the bulk density, the better. I would probably lay a hammer beam both on the brick and the leca and let the roof truss tie them together. In the leca block, you fasten with a leca nail, and in the brick, preferably with a nail plug where you drill right through the hammer beam. Steel bands can also be considered. You must size the fastening with regard to the lifting forces, which can be large when it comes to roofs.