Concreting is not as difficult as you may think

Press, Volume CXVI, Issue 34044, 7 January 1976, Page 5

Concreting is not as difficult as you may think

Have you ever thought of doing your own concreting? Many of us may think it is a job that only a professional can do, but in fact the average handyperson should have little trouble in doing simple work.

When your “simple” effort turns out a success, you may be confident enough to try something more complicated, but the subject of this article will be basic, uncomplicated concrete work.

In the old days concreting was hard work (it often is still) but the actual mixing of concrete, which was often done in a mixer turned by hand, is virtually always done by a mixer by either an electric or petrol motor. The average handyman will be unlikely to have enough work to warrant buying his own mixer, so he should borrow one from a friend or hire one.

For very small amounts of concrete the mixing can be done by hand with a shovel, but for more than a barrow-fill or two a machine is the sensible, and better way to do it.

The usual noncommercial mixer mixes a barrow-full of concrete. This means a proper steel barrow with a pneumatic tyre, not the tin variety on a skinny pram wheel. The whole thing would collapse

if a load of wet concrete was dumped into it. Even if it stood up it would be almost impossible to wheel. The ingredients and tools for concreting are cement, sand and gravel, water, a mixer, barrow, shovel and one or two trowels and perhaps a straight-edge.

In Christchurch the sand and gravel can be bought ready-mixed and is known as “premix.” The two can be obtained separately, of course, but some knowledge would be required to get the right mixture. The mixture strength for such work as a path should be one shovel of cement to five shovels of premix. A lesser amount of premix, say four shovels to one of cement, will make a "stronger” mix but it is quite unnecessary. The exact amount of water can only be judged by experience, but the mixer will take 10 shovels of premix, two of cement, and perhaps two buckets of water. The water, or at least most of it, should be put in the rotating mixer first, the premix and cement added, and the remaining water added if it looks to be necessary.

The mixture should not have dry patches in it, the premix and cement should be well mixed in and wet, but neither should it be too thin and runny.

A path should be 3in thick and it should be filled in small sections at a time; don’t fill the whole area with a thin layer first then put down another layer.

The straight-edge should be used to level the concrete off, working it backwards and forwards as the concrete is moved forward. Finishing should be done with a flat trowel, and here is where “practice will make perfect.”

Paths do not need ex-1 pansion strips inserted but j if you are worried about: cracking you can inscribe a> groove across the path 1 every few feet. If a crack 1 does occur it will do so in the groove and will not be] so obvious. A simple tool I is available for making the groove.

For drives the concrete) should be 4in thick, with perhaps a thicker strip along the edges. Reinforc-i ing is not necessary even j for a drive, but grooving! should be done every 10ft or so.

Retaining walls, base-; ment walls and other load-) bearing structures will have to be reinforced, but; for details you should ring your local council and ask! a building inspector what: is required in the way of I materials.