ᐅ Cast-in-place exposed concrete entrance platform construction

Created on: 27 Feb 2024 09:38
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danielg40
Hello,

I would like to create a concrete platform in front of our front door as exposed concrete.
2 x 0.9 m (3.3 x 3 feet) and about 20 cm (8 inches) high.
It should be just a single low step.
Later, I plan to drive over it with the paving stones.

What exactly should I keep in mind?
Of course, smooth formwork panels.
I also have a concrete vibrator.
(In the past few weeks, I already poured 7 tons of concrete for the garage construction, ring beam, and lintel, but in those cases, the appearance wasn’t important;-))

We have a 1 m (3.3 feet) roof overhang and basically no precipitation there apart from drizzle, but I still plan to create a 1% slope.

From what I’ve read, I should use a good ready-mix concrete, like C25/30 with 0-8 mm (0-0.3 inch) aggregate?
I would place one layer of reinforcement mesh in the middle.
It basically only has to hold its own weight, but it must be smooth.
Some roughness should be preserved to avoid it becoming slippery.

For separation from the facade and front door, I would lay an 8-10 mm (0.3-0.4 inch) thick building protection mat?
That would leave the gap at the door and facade visible.
Can I later fill that with something like Sikaflex Pro 1 concrete gray 1K polyurethane sealant?

For the chamfer, I was thinking of using 45-degree triangular wooden wedges like shown in the picture?

Attached are a photo of our entrance and an image of how I imagine the platform.
Afterwards, I would seal it somehow.

Any tips and suggestions?
Close-up of a hammer striking a yellow wooden formwork frame during construction work

Outdoor area: new concrete platform as entrance step in front of the door with tiled path

Exterior view of a house: dark front door, small window, planter, and shoes in front of the door
Nida35a28 Feb 2024 09:31
This is how our paved area looks with a granite edge. The path features a random pattern with stones that are 10% lighter in color to prevent it from looking too long and monotonous.
Entry area: grey door, shoe rack, shoes, yellow hose, and paved path.
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danielg40
28 Feb 2024 21:29
So,
I will line it with coated particle boards.
In the end, it will actually be about one metric ton of concrete.
I’m now digging 30cm (12 inches) down all around the outside.

Any tips on how to best achieve a smooth finish by hand? Can you actually over-vibrate the concrete?
Like having too much aggregate at the surface, which might later cause flaking?
Baugrube vor der Haustür mit Holzrahmen, Stahlstiften, Erde und Kies für Fundament.

Fundament-Schalung aus Holz im Erdgraben neben der Hauswand; Erde, Kies und Werkzeuge sichtbar.

Holzformrahmen für eine kleine Vorstufe vor der Haustür, Erdreich und Kies.
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danielg40
28 Feb 2024 22:48
Is it worth buying a proper floor trowel, or is a small regular 30cm (12 inch) trowel enough for this area?
What would you roughly estimate regarding when to start troweling with the current weather of about 12°C (54°F)?
Pouring concrete on Saturday around 8-9 a.m., smoothing/troweling approximately 5-6 hours later around 3 p.m.?

Is it advisable to sprinkle cement into the surface while troweling?
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danielg40
29 Feb 2024 11:49
So,

I just spoke with a landscaper, and he said...
He has always had good results with freshly directed/consolidated concrete.

The last layer should be poured properly wet and then leveled smoothly together with a screed board and a vibrator.
That’s enough; he has never done any further finishing afterward.

Now I’m wondering what is better.
As I said, I don’t need a perfectly smooth, glossy surface. It should just be even and free of concrete craters and protruding sharp edges.

If I want to smooth it after the curing process later, I probably shouldn’t pour it too wet.

What should I do?
Nida35a29 Feb 2024 17:18
Do it as the landscaper advises, and it will be fine.
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danielg40
29 Feb 2024 19:39
Nida35a schrieb:

Just do as the landscaper says, then it will be fine.

Are you saying that from experience, your own experience?
Could you perhaps find a picture or do you have a picture of what it could ideally look like if I just follow those instructions?

Thanks in advance.