Basement Construction

is much better without concrete kickers. There are several simple alternatives. First, an explanation of problems with concrete kickers. This image is taken from the web site of a company that sell the hydrophylic tape you see on the top .... of a kicker still with laitance on the top, with holes at the bottom and clearly soaking up water like a sponge.

You won't have much success with waterproof concrete used with concrete kickers. If a hydrophylic strip worked it should be under the kicker as well. But hydrophylic strips often fail because the problem is voids in the concrete itself. How might the workforce above have produced such poor concrete in their kicker? This image is taken from the Grace Adprufe System BBA Certificate 06/4319. The concrete is being segregated (bleeding) by the poker held still and obviously any concrete in the kicker is sinking into the slab. So the concreting gang will tend to leave the kicker empty or fill it later when the slab is setting. With what is anyone's guess. I would say the same concrete set aside until it is stiff and setting itself and out of time is the most usual. If you pokered 100mm high good, fresh concrete in a kicker hours after the slab was formed. Everyone would be splattered from head to toe and the kicker almost empty. You cannot form a waterproof concrete kicker, so concrete kickers are banned if you want a waterproof structure. You might think that if you get a guarantee with your waterproof concrete For instance at an extra £80 or so a m³ from Cementaid for Caltite Or an extra £1200 plus £40 or so a m³ from Pudlo (typical for self builders) (Prior to its going into administration and being sold twice by 11 July 2025. I don't know what changes the new owners may make in future.) that they will come and repair your kickers for you. Don't be silly. They aren't that daft. Kickerless Formwork. All these ways to avoid kickers are acceptable. These timber props are fixed to the slab and made of 4x2 that is eventually reused in the building, making it very cheap. A different way to fix the formwork in the correct position. The uncropped photo and another of the same basement 3 weeks later is toward the end of this page. This is a timber plate and concrete screws fixing it to the slab. And another. Note the L shape upright made with two 4x2s screwed together. Very straight and strong. Doka from Mabey bolted down. FastForm. Also bolted down. Kickerles kickers are available to buy. If kickers have any structural benefit at all it is preventing grout loss. But expanding foam is even better. Here is the photo I cropped to use above. I took this when I delivered the FRP threaded rods and nuts. They didn't buy anything else from me. They have spaced the formwork with measured pieces of wood. These came out as they put in the threaded rods with thin nuts to control the width instead. 3 weeks later I collected the steel waler plates they hired. This is the completed kickerless concrete. It is a shame this basement has a flat top and not an upstand. It was built by a contractor who, I suppose, did not question the drawings.

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