ᐅ Exterior Basement Staircase

Created on: 25 Aug 2014 12:06
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Marc82
Hello,

I am new to this forum. I couldn’t find any posts related to my topic, so I’m starting a new thread.

We are facing a small problem:

We have bought a house built around 2000, with a basement made of reinforced concrete and EPS insulation.

That’s the basic information for now.

We plan to install a basement door on the side, so we started digging and, as expected, there is no frost protection strip beneath the basement (which is 2.5m (8 feet) below ground level). Below the 25cm (10 inches) slab, there are about 10–20cm (4–8 inches) of gravel, and underneath that is rocky soil.

How should we proceed to avoid damaging the house during this work? A basement entrance door is essential in our case, so there is no alternative.

I would appreciate any quick advice.

Best regards
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Wastl
26 Aug 2014 14:16
If no building permit or planning permission is required, then you don’t need one. In our development plan, exterior stairs are not permitted. In other words, you have to apply for an exemption. So in your case, you will need one.

As a layperson, I would install frost protection and insulation for the exterior stairs. Why not? I wouldn’t touch anything under the house. The connection between the house and the exterior stairs is the crucial part. I have no idea whether they should be simply attached or if expansion joints are necessary.
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Marc82
26 Aug 2014 14:32
Thanks for the helpful response. I will check the building permit / planning permission with the local authority.

So, a frost protection strip under the stair slab on three sides, except on the house side, to avoid unnecessary undermining – insulating the frost protection strips on the outside plus insulating the underside of the slab – maybe slightly extending under the house’s slab or flush with it. The retaining walls would then continue directly on the frost protection strips. I would definitely include an expansion joint.

Does anyone have other suggestions? 🙂
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Marc82
27 Aug 2014 11:16
According to the building authority, no building permit / planning permission is required for an exterior staircase added afterwards, only for a garage or similar outbuildings.
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Marc82
28 Aug 2014 07:41
Does anyone else have any design suggestions or important points that the construction company should not overlook?