self build waterproof basement formwork membrane concrete
 

A few mistakes, made by others, to avoid yourself.

  self build basement
  1. Getting planning permission for the front of the new house to be in the same place as the house you will knock down - but not getting the old house surveyed first.

  2. Not organising building control or latent defects insurance before you knock the previous house down or even before you start work.

  3. Not sending in a Form F10 to the Health and Safety Executive before you start work.

  4. Not studying the CDM Regulations and how they apply to you. (They apply to everyone so they do apply to you).

  5. Not getting a good soil investigation.

  6. Not thinking about who you need to build or help you build.

  7. Not having anyone competent to at least keep an eye on all contractors.

  8. Not doing any basic research to understand the materials you will use if you are in charge, for instance the different ways to buy and have concrete delivered; what men can lift and what requires a crane.

  9. Saving money.

  1. Getting planning permission for the front of the new house to be in the same place as the house you will knock down - but not getting the old house surveyed first.


    Picture the excavation for your basement. It is the size of your new house, plus half a metre all round, plus sloping sides to be safe.

    Everything within 3m of your old home is gone.

    How do you mark, down the bottom of a deep and muddy hole, where the front of the new house should be?

    Many people need a land survey before the old house is demolished and to bring back the same surveyors to mark the corners down the excavation.

    Clearly it will be easy to realise later the house is in the wrong place but few appreciate how difficult it is down a hole with wilderness left all around.


  2. Not organising building control or latent defects insurance before you knock the previous house down or even before you start work.


    If you want someone other than the council to do your building inspections then they must give you permission before you knock the previous house dowm.

    If you start before getting your latent defects insurance fully in place they will charge you a supplementary premium of several thousand pounds.


  3. Not sending in a Form F10 to the Health and Safety Executive before you start work.


    Projects over a certain size are required by law to submit a Form F10 to the Health and Safety Executive and to display the form in the site office alongside statutory insurance certificates.


  4. Not studying the CDM Regulations and how they apply to you. (They apply to everyone so they do apply to you).


    There is safety for bullsh%t purposes and there is safety to keep you out of jail. Find out how to keep yourself out of jail here: www.hse.gov.uk


  5. Not getting a good soil investigation.


    I have a whole page of warnings on this but still many people who phone me are trying to cut corners.

    No one, in my experience, who spent £3,000 on a thorough soil investigation wasted a single penny over designing not knowing what was in the ground, on inappropriate work that went to waste etc. etc. etc.

    Some years ago now, a client who knows nothing about construction but wants to be in charge of everything, paid off a local builder who had made a start on a basement, paid me off for removing all that previous work, paid off a piling contractor for then putting in 94 piles to support the sides, had me back only to find out his drainage was all wrong ........

    When I first went there I looked back at his soil report. I found these two phrases within it:

    "A desk study was not commissioned as part of this basic investigation."

    "a detailed discussion of all the problems that may arise during the proposed redevelopment scheme is beyond the scope of this report."

    The man had no doubt been offered these two additional services but declined them and after spending nearly £100,000 pounds he still only had a hole.


  6. Not thinking about who you need to build or help you build.


    Your new home cannot be built by one or two foreigners over here to teach Latin dance or study humanities at university if they never used a shovel before. Yet 2 clients in the past thought that with me there as well they could.

    You need different people at different times. Groundworkers, digger driver, lorries, strong labourers, carpenters, steel fixers and so on.


  7. Not having anyone competent to at least keep an eye on all contractors.


    One job I started I realised we were digging deeper than expected, removing more material from site than expected and digging nearer to the boundaries than expected.

    It transpired that the clients had been hoodwinked by the demolition people into the advantages of leaving a solid layer of hardcore all over the site so it would be clean for those following on.

    In fact, they left 800mm of hardcore all over the site which might mean they were paid to remove the house they demolished but they just left it.

    The clients paid twice for their old house to be taken away.

    You only need someone to talk to before saying yes to what might sound a good idea at the time. I will consider what follows on and whether it really helps, so would your architect and structural engineer. They and I are people who work for you. But if you do not know it will be obvious and you will be caught out by someone wise to an opportunity.


  8. Not doing any basic research to understand the materials you will use if you are in charge, for instance the different ways to buy and have concrete delivered; what men can lift and what requires a crane.


    I cringe when I hear self builders trying to get a good deal without any of the industrial jargon. They may as well have 'Mug' written on their heads.

    I cringe when the concrete turns up in a truck that mixes it on site when we needed readymix so that we could add chemicals at the correct dose.

    I cringe when they hire a concrete pump too small and expect several tonnes of concrete to be carried to the far end in buckets - within 30 minutes because concrete sets.

    I cringe when they try to hire plant from a tool hire company or a tool from a plant hire company.


  9. Saving money.

  10. Saving money your way, not mine, usually ends up being expensive.

    I should say that the 3 most expensive ways self-buiders try to cut corners are

    1. Not excavating fully so they get cave ins that are dangerous and more expensive to clear after construction has started.

    2. Only having a couple of labourers to work with. Labourers have no skills so you end up doing most of the work. This takes far longer. The right approach is to hire 2 carpenters, 2 bricklayers or groundworkers and 1 strong labourer.

    3. Trying to provide scaffold on the cheap. Men get injured falling off scaffold that is unstable or weak. One man, who has worked for me again since, went back to finish a job where I refused to continue and ended up with cracked ribs. No one works well after being frightened or injured. Poor scaffold creates poor value workers.