A new way to survey residential plots

By MUNGAI KIHANYA

The Sunday Nation

Nairobi,

30 July 2017

One of the challenges of the normal rectangular plot of land – the so-called “50 x 100” – is that, when two are placed side-by-side to make a “quarter-acre”, the shape changes from to a square (“100 x 100”).

There is no law or regulation saying that a residential plot must be a rectangle whose length is twice its width. I have seen many plots that don’t have that profile. A good number of “corner plots” are not even rectangles or four-sided – I own one that is a heptagon (a seven sided shape)!

I think our surveyors should change from the 1 x 2 rectangle to one that retains the ration of length to width every time it is subdivided into two halves. This is the way that an A4 printing paper produces two A5s with the same ratio of sides.

I explained how the dimensions of A4 paper are arrived at in 2011. It turned out that the ratio of the length to the width is the square root of 2 (that is, 1.4142). We can apply the same ratio to a plot of land.

The best approach would be to start from small plot and build upwards. The so-called “eighth of an acre” is a good starting point. It is normally surveyed as 15m by 30m. Thus its area is 450 square metres.

Let’s call this area and ‘eighth-plot” instead of an “eighth of an acre”. Applying the square-root-of-two ratio, the dimensions of this plot will be 17.85m by 25.23m. It is exactly the same area as the 15m by 30m plot, only that it’s a little wider but a slightly shorter. True: those measurements are awkward, but their advantage becomes apparent when two plots are placed side-by-side.

The length of the new, larger plot is twice the width of the eighth-plot; that is, 17.85 x 2 = 35.7m. Its width is equal to the length of the smaller plot; that is, 25.23m. The ratio of these new dimensions is 1.415. This is almost the same as that of the previous (smaller) plot. The small difference is due to the rounding off of the answers to the nearest centimetre. Nevertheless, to the unaided eye, the two plots will appear similar in shape; only differing in size.

Since the larger plot is double the area of the eighth, we can call it a “quarter-plot”. When two quarters are place side by side, they will make a “half-plot” measuring 25.23 x 2 = 50.63m long and 35.7m wide. The length to width ratio remains 1.414.

A “full-plot” is formed by joining two halves and its dimensions will be 50.63m by 71.4m. The area of this “full-plot” is 3,600 square metres. It’s an awkward number, no doubt, but so is the current 450 square metres for an eighth-plot!

With these dimensions, we can invent a new standard residential plot: the one measuring 50.63m by 71.4m, or an area of 3,600 square metres. What do you think?