One Size Doesn't Fit All

Posted by nseymour on November 26, 2019

 Comparison SuperDeep.jpgWhen it comes to choosing the correct rainwater system for construction projects in the UK, it is definitely not a case of one size fits all. Here we take a look at how one of the leading manufacturers has developed a portfolio of products designed to cope with the wide range of rainfall condition experienced in different areas of the country.

If there is one characteristic that British people are known for all over the World, it’s probably our obsession with the weather. As children, we only seem to remember the long hot days of summer. Did they really happen? Did our Dads actually manage to keep the barbecue alight through the downpours? Our rose-tinted memories may say “yes” but reality was somewhat different!

And when the first flakes of winter snow arrive, does the whole country go into panic mode with road, rail and airport disruption at every turn? Oh, yes it does!

The real problem with the British weather is that it is so variable. In some areas of the country – Wales, Scotland, The Pennines etc, we see a huge amount of rainfall – as much as 180 inches per year, making them some of the wettest locations in Europe.

In other areas – London, East Yorkshire, Norfolk and Suffolk, much less rainfall occurs – as little as 24 inches per year, making them some of the driest areas of the country. It’s also a little-known fact that Colchester, Clacton and Ipswich actually have less annual rainfall than the Middle Eastern cities of Jerusalem and Beirut. Hard to believe, but true.

Right system, right capacity.

But what does all this mean in the real world of UK construction? The simple answer is to provide the market with guttering systems with the appropriate capacity to do their job with optimal efficiency, whatever the prevailing conditions may be.

For areas of high rainfall intensity, Kayflow has developed a SuperDeep170, a PVC profile guttering system, designed to handle a much higher flow rate than standard guttering.  With a market leading flow rate of around 10 litres per second, it has the capacity to carry 10 times more water than a standard half round gutter and at least five times more water than a standard deep system.

Kayflow see SuperDeep170 as being ideal for large commercial developments such as agricultural buildings, hospitals, schools and factories. These types of buildings generally have large roof areas with high run-off potential and therefore need a much bigger capacity system. According to Kayflow, SuperDeep170 can even reduce the number of downpipes needed with consequent reduction in the frequency and lengths of below ground connections etc.

Super Strength

A consequence of increased capacity is an increase in potential weight-loading and resulting pressure on the gutter fixing system.  The high strength bracketing developed for SuperDeep170 is said to be capable of holding over 125kg on one unit and well able to handle the gutter system running at full capacity.

Expansion & Contraction

Heat build-up is sometimes seen as a downside to large capacity, PVC guttering systems due to the volume of material in their composition.  Thermal expansion and contraction can result in an increased risk of leaks but Kayflow has raised the benchmark for the industry by co-extruding the SuperDeep170 gutter profile onto a white base with a black or grey outer skin.  The white base material helps reduce heat build-up through reflection, whereas a black or dark, through-colour would tend to absorb heat and increase the risk of expansion/contraction.

The dark outer skin, co-ordinates with other components in the range providing the required aesthetic to satisfy the demands of architects and other construction professionals.

Wider range

Where high capacity systems are not a requirement, Kayflow has a range standard rainwater products, manufactured in round, square, deep and ogee profiles in a range of colours, all up to the job of rainwater disposal from the roofs of everything from garages to houses, flats and large commercial buildings.

Also available are half-round and ogee profiles in cast iron effect in black with specially moulded components that closely reflect the traditional detailing of cast iron systems.

So, whether you are building in the wetter parts of Wales and the West or the dryer corners of East Anglia and the South, you can be confident that the right rainwater system, with the right capacity, profile finish and colour is little more than a phone call away.


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