Concrete fence posts widen

Even cement-bonded XPS construction panels (XPS is "just" extruded plastic foam) are hardly stable enough to hold that, and are apparently intended for wet areas (bathroom / kitchen), but I cannot imagine that they will last long if exposed to the weather permanently.

They write: for outdoor use, waterproof, weather-resistant...

O.K. But stable enough??

O.K. But stable enough??

Certainly not and on top of that a lot of effort, appearance and also cost??? The idea from to basically slip the formwork blocks over sounds good too but then it becomes too thick, as you say. Besides, you could just build such a "tower" out of formwork blocks anyway and wouldn’t need the old post. You would only save yourself the demolition. I would - reluctantly - remove the old pillars; it’s not rocket science and "merely" manual labor that you can do yourself. Afterwards, I would make it exactly fitting so that my new fence really looks good. Installing new and color/visually matching metal posts would ultimately be cheaper and above all much nicer than a homemade semi-version.

O.K. But stable enough??

Characteristics

[*]Extremely pressure resistant (380 kPa)
[*]Absolutely moisture resistant, waterproof and rot-proof
[*]With special coating on both sides
[*]Directly tileable, fillable and plasterable
[*]Extremely versatile for indoor and outdoor use
[*]Very good thermal insulation properties (WLG 035)
[*]With general building authority test certificate (abP)

Technical Data

Manufacturer	doitBau
Compressive strength	380 kPa
Thermal conductivity group	WLG 035
Temperature resistance	-50 to +75°C
Density	35 kg/m³
Dimension per panel	1300mm x 600mm (0.78m²)
Thickness per panel	Optional 4, 6, 10, 20, 30, 40, 50mm
Scope of delivery	One panel (0.78m²)

Certainly not, and in addition a great effort, aesthetics and also costs??? The idea of to basically slip the formwork blocks over sounds good too, but then it gets too thick, as you say. Besides, you could just build such a "tower" out of formwork blocks anyway and wouldn't need the old post. You would only save yourself the demolition. I would - reluctantly - remove the old pillars; that's not rocket science and "merely" manual labor that you can do yourself. After that, I would make it just right so that my new fence really looks good. Setting new and color/visually matching metal posts would ultimately be cheaper and above all much nicer than a homemade semi-version.

well, the costs are certainly manageable in a do-it-yourself approach And when removing the posts or resetting posts, I’m afraid that the paving stones in front of and behind the fence will then lose their stability. I only have a spade’s width of space between the pavers. Otherwise, I would have offset the posts accordingly...

Properties

[*]Extremely pressure-resistant (380 kPa)
[*]Absolutely moisture-resistant, waterproof and rot-proof
[*]With special coating on both sides
[*]Directly tileable, can be filled and plastered
[*]Extremely versatile for indoor and outdoor use
[*]Very good thermal insulation properties (WLG 035)
[*]With general building supervisory test certificate (abP)

I cannot assess the thing with the paving stones. But I would rather see this material as something with which I can build over or clad outdoors, etc., that’s how I see and read it. Pressure resistance, for example, also applies to an OSB or drywall wall, but I wouldn’t attach heavy objects to it just for that reason. Also, the notes that it can be tiled over, etc., rather suggest that it is ultimately like a stronger but still kind of OSB/drywall version for outdoor use, e.g., for cladding something. But as I said, that is just my opinion, and I believe that this involves considerable effort, because you have to fill, plaster, tile, etc. afterwards... work on it until it looks good. For me, the suggested wood version would be more appropriate there. A lath construction all around and wood cladding attached, which no longer needs filling or plastering and also offers more stability.