Got to build a driveway

Germany here.
Our local council is forcing us to build a second driveway / parking lot on our ground. Must destroy part of the garden for this, very sad but hey I've got no choice, long sad story, please don't ask...

Thing is, as I'm going to make it only to satisfy them, and in reality it'll never see a car, at least for the next few decades we'll reside here. So I want to make it as easy and cheap and possible.

Question:
normally a depth of 30cm of sand/stones/whatever is recommended.
How much will things be different if I make it much less deep, say 20cm, or 10cm?
Anyone have recent experience?
Cheers,

Comments

  • Pross
    Pross Posts: 40,217
    edited February 2023
    It really depends on the ground conditions and it’s bearing capacity. There is good advice n this site https://www.pavingexpert.com/subbase but in most cases I would say 150-200mm would be enough unless the ground at formation level is very soft or you are parking something very heavy on it (you’ll need to remove the full depth of topsoil though). Just make sure everything is well compacted.

    Edit - if the Council is insisting you provide the driveway then it may be you’ll have to comply with any design standards they have. The depth required in the UK for new build houses is covered by the NHBC design guidance and varies depending on the ground bearing capacity. Some Councils will have their typical construction details.
  • DeVlaeminck
    DeVlaeminck Posts: 8,719
    I know you said don't ask but this is intriguing.
    [Castle Donington Ladies FC - going up in '22]
  • monkimark
    monkimark Posts: 1,462
    What sort of drive are you going to install?
    If you're never going to use it then it doesn't really matter what the sub base is as it'll never get loaded.
    If you occasionally drive on it then don't you just need two tyre wide strips of paving so you can maintain most of the lawn? Or maybe just some of that plastic grid stuff that the grass grows through (you'll stilll need sub base of some sort)
  • orraloon
    orraloon Posts: 12,612
    As Pross says above, have a look around pavingexpert.com.
  • monkimark said:

    What sort of drive are you going to install?
    If you're never going to use it then it doesn't really matter what the sub base is as it'll never get loaded.
    If you occasionally drive on it then don't you just need two tyre wide strips of paving so you can maintain most of the lawn? Or maybe just some of that plastic grid stuff that the grass grows through (you'll stilll need sub base of some sort)

    the plastic grid stuff is brilliant.

    Alternatively if you need something that looks like a drive then just put edges in, weed proof membrane then cover in gravel
  • pep.fermi
    pep.fermi Posts: 308
    edited February 2023
    OK, here the long story.

    Rule from the council is that every house MUST have at least 2 carparks. Not sure in the whole council, but for sure at least our street. And they count only if they are next to each other, not in-line (our carpark #1 has space for maybe 6 cars, in-line, still count only as 1). So much so for Climapolitic and GreenEnergy, that (almost) everybody pretends to be in favor for because it's trendy and politically palatable, but in reality (almost) nobody give it a damn.
    BTW I'm a car-hate hard-core environmental activist.

    So we knew the rule all along. But 2018 when we applied for building the house we still asked to build ONE car park. As expected, application immediately rejected. Next we applied with TWO carparks, everything else same. As expected, application immediately approved. Then we built the house and we built ONE carpark. Knowing of course this was likely to cause us conflicts later on. Now 4yr later council is asking "what about your second carpark"?

    So I've got to build a 2nd carpark, to satisfy them. Of course this means paving the ground, few 1000s eur cost and several hrs labor, and many tons of CO2 emission. But hey rules are rules, even if they are bad for everybody.

    But as I'm going to do this against my wish, only because they force us, and this 2nd carpark will never see a car for several decades to come.... I'd rather build it cheaper and easier.

    Clear?
  • rjsterry
    rjsterry Posts: 27,487
    1985 Mercian King of Mercia - work in progress (Hah! Who am I kidding?)
    Pinnacle Monzonite

    Part of the anti-growth coalition
  • laurentian
    laurentian Posts: 2,372
    I know next to nothing about this but surely the crucial thing is whether the council have a specification or minimum standard for a "car park".

    If they do then you have no option but to build to at least that minimum standard.

    If they don't then surely the design and specification are up to you and you do it in the cheapest, most envronmentally sound way that you can.

    What's more, if they don't stipulate a minimum size, cost savings can be made here too.

    Just my 2p worth
    Wilier Izoard XP
  • Pross
    Pross Posts: 40,217
    pep.fermi said:

    OK, here the long story.

    Rule from the council is that every house MUST have at least 2 carparks. Not sure in the whole council, but for sure at least our street. And they count only if they are next to each other, not in-line (our carpark #1 has space for maybe 6 cars, in-line, still count only as 1). So much so for Climapolitic and GreenEnergy, that (almost) everybody pretends to be in favor for because it's trendy and politically palatable, but in reality (almost) nobody give it a damn.
    BTW I'm a car-hate hard-core environmental activist.

    So we knew the rule all along. But 2018 when we applied for building the house we still asked to build ONE car park. As expected, application immediately rejected. Next we applied with TWO carparks, everything else same. As expected, application immediately approved. Then we built the house and we built ONE carpark. Knowing of course this was likely to cause us conflicts later on. Now 4yr later council is asking "what about your second carpark"?

    So I've got to build a 2nd carpark, to satisfy them. Of course this means paving the ground, few 1000s eur cost and several hrs labor, and many tons of CO2 emission. But hey rules are rules, even if they are bad for everybody.

    But as I'm going to do this against my wish, only because they force us, and this 2nd carpark will never see a car for several decades to come.... I'd rather build it cheaper and easier.

    Clear?

    All of those impacts could have been reduced had you built what you got approved at the time. Whilst I appreciate you didn't want to provide it you admit you expected it to come up later when it will cost more and will also result in greater CO2 emissions.

    I would suggest asking the Council if they will accept some form of cellular system whether that is gravel filled or topsoil / seed. It will still need the sub-base but is better from a drainage point of view and, arguably, appearance (I've previously specified this on a couple of sites including a school where additional parking was required https://www.corelp.co.uk/core-drive/ I'm sure there is similar in Germany).

    Ironically rules in the UK have been tightened up to reduce the amount of people building driveways on their front gardens.
  • Pross said:


    All of those impacts could have been reduced had you built what you got approved at the time.

    Sure, of course.
    Well, I decided to gamble, there was a slim chance I could get away with it.... eventually it turned out no, I didn't.
  • On the website of your town/borough (Gemeinde), you'll find its local ordinance about parkplaces (Stellplatzsatzung). The construction requirements won't normally be very specific, e.g. to be of paving/interlocking stones or similar air-/water-permeable surfacing, on a substructure appropriate to the traffic load, constructed in such a way that rainwater can seep away and not on to public areas, etc.

    Many of the simpler, cheaper ideas proposed by other posters should therefore be okay
    - unless when you got the building permit (Baugenehmigung), it required the two parkplaces to be identical or gave other specifications, like defining the required surfacing or saying the whole parkplace (typically 2.5 x 5 m) has to be paved – if not, the two strips idea by Monkimark becomes feasible, say two 65 cm wide strips of concrete-grid blocks/grassblock (Rasengittersteine) with 1 m grass between them. If the whole area is to be paved, you could perhaps follow Pross' cellular system idea.

    If the subsoil is sandy, you could probably just excavate to a depth of 12 cm, compact the subsoil, and install 8 cm concrete-grid blocks on a 4 cm base course of fine-crushed stone (Splitt). If the subsoil is loam or clay, so more frost-sensitive, an extra 10-15 cm of excavation would be advised, plus a further 5-15 cm of excavation if you live in an area where more severe frosts occur (with a couple of exceptions, almost anywhere east of a line Kiel-Freiburg) and this filled with a subbase of crushed rock (Schotter).

    Plastic-grid is another option as final surfacing, and easier to install, however usually a bit dearer than concrete-grid per qm. But even with it, the overall total construction depth remains valid.

    Note that if you get a builder in to construct the parkplace, he may be reluctant to do the job (or give any guarantee) if your design diverges a lot from the guidelines for the standardisation of traffic pavements (RStO), even though your parkplace isn't a public traffic area. The RStO requires, for example, for lightly-trafficked areas a total construction thickness of min 27 cm, and min 40 cm when the subsoil is frost-sensitive. A builder would cost between 85 and 135 € per sq. m. öf paving.

    Another possibility is to see if your council will agree to a settlement payment (Ablösebetrag). The Stellplatzsatzung will usually have a text in it, saying the the number of parkplaces required can be reduced upon request in return for a payment. However, there is no right to this settlement, and the council will want persuasive legal or factual reasons before agreeing. The settlement amount varies from under 2000 € to 6000 €, depending on locality.

    If you end up with a parkplace you don't want/need, you could always try and recoup some of your expenditure by offering it out to rent. This is common in Germany in localities with too few parkplaces, one can usually ask 30 € per month, up to 90 € if you live in a large city.