Hello,
I have old fence posts that are set in concrete in the ground. They are made of concrete. I now have new fence panels that are narrower than the old ones, and I would like to widen the existing fence posts. My idea was to create a formwork and simply apply concrete with a thickness of 3–7 cm (1.2–2.8 inches) using the formwork.
The existing posts are painted with wall paint. My concern is that the new concrete might not bond properly with the old one. How can this be prevented? Or does anyone perhaps have another idea?
I look forward to your replies.
Best regards
Michael
I have old fence posts that are set in concrete in the ground. They are made of concrete. I now have new fence panels that are narrower than the old ones, and I would like to widen the existing fence posts. My idea was to create a formwork and simply apply concrete with a thickness of 3–7 cm (1.2–2.8 inches) using the formwork.
The existing posts are painted with wall paint. My concern is that the new concrete might not bond properly with the old one. How can this be prevented? Or does anyone perhaps have another idea?
I look forward to your replies.
Best regards
Michael
superzapp schrieb:
Even cement-bonded XPS construction boards (XPS is "just" extruded polystyrene foam) are hardly stable enough to support that, and although they are probably intended for wet areas (bathrooms / kitchens), I can’t imagine they will last long if exposed to weather permanently. They claim: for outdoor use, waterproof, weather-resistant...
K
knalltüte8 Jul 2020 11:36Okay. But is it stable enough?
P
pagoni20208 Jul 2020 12:21superzapp schrieb:
O.K. But stable enough?? Definitely not, and it would be a lot of work, plus affecting the appearance and increasing costs.
The idea from @cschiko to basically slip formwork blocks over the posts sounds good, but then it would become too thick, as you said. Besides, you could just build such a "tower" entirely out of formwork blocks and wouldn’t need the old posts at all. You would only be saving yourself the effort of demolishing the old ones.
I would—reluctantly—remove the old pillars; it’s not complicated and is mostly manual labor that you can do yourself.
After that, I would make the new fence fit perfectly so it really looks good. Installing new metal posts, matching in color and appearance, would ultimately be cheaper and especially much nicer than a homemade semi-finished solution.
superzapp schrieb:
O.K. But stable enough??Properties- Extremely pressure resistant (380 kPa)
- Completely moisture resistant, waterproof, and rot-proof
- Both sides with special coating
- Suitable for direct tiling, filling, and plastering
- Highly versatile for indoor and outdoor use
- Excellent thermal insulation properties (WLG 035)
- Certified with general building inspection approval (abP)
Technical Data
| Manufacturer | doitBau |
| Compression strength | 380 kPa |
| Thermal conductivity class | WLG 035 |
| Temperature resistance | -50 to +75°C (-58 to 167°F) |
| Density | 35 kg/m³ |
| Dimensions per panel | 1300 mm x 600 mm (0.78 m²) (51 inches x 24 inches (8.4 ft²)) |
| Thickness per panel | Available in 4, 6, 10, 20, 30, 40, 50 mm (0.16, 0.24, 0.39, 0.79, 1.18, 1.57, 1.97 inches)</TD] |
| Scope of supply | One panel (0.78 m²) (8.4 ft²)</TD] |
pagoni2020 schrieb:
Definitely not, and it would also be a lot of effort, plus the appearance and cost???
The idea from @cschiko to basically slip the formwork blocks over sounds good too, but as you said, that would make it too thick. Besides, you could just build such a "tower" out of formwork blocks anyway and wouldn’t need the old post. You would only be avoiding the demolition work.
I would—reluctantly—remove the old pillars; it’s not rocket science and just manual labor that you can do yourself.
After that, I would make everything fit exactly so my new fence really looks good. Installing new metal posts that match in color and appearance would ultimately be cheaper and, above all, much nicer than a makeshift semi-version. Well, the costs are probably manageable with a do-it-yourself approach. And when removing or resetting the posts, I’m afraid the paving stones in front of and behind the fence might lose their stability. I only have space for the width of a spade between the pavers. Otherwise, I would have positioned the posts differently...
P
pagoni20208 Jul 2020 12:51Camiflo schrieb:
Features
- Extremely pressure resistant (380 kPa)
- Completely moisture resistant, waterproof, and rot-proof
- Special coating on both sides
- Suitable for direct tiling, filling, and plastering
- Highly versatile for interior and exterior use
- Very good thermal insulation properties (WLG 035)
- Certified with general building authority approval (abP)
I can’t comment on the paving stones. However, I would see this material more as something you can build over or use as cladding in outdoor areas, from what I understand and have read. For example, OSB or drywall walls are also pressure resistant, but that doesn’t mean you can mount heavy objects on them. The indications that it can be tiled over or plastered suggest that it is basically a stronger version of OSB/drywall for exterior use, for example for cladding purposes. But as I said, that is just my opinion and I think it involves quite an effort because you then have to fill, plaster, tile, and work on it until it looks good. For me, the suggested wood version makes more sense: a slatted frame on the outside with wood cladding attached, which doesn’t require filling or plastering and also provides more stability.Similar topics