The recent spate of heavy and destructive hailstorms that caused severe damage to property in Gauteng has proved to be no match for a range of Rainflo unplasticised polyvinyl chloride (PVC-u) gutters and downpipes, says water reticulation, drainage and pipefitting systems manufacturer DPI Plastics.

A hailstorm that hit the East Rand in October caused substantial damage to the roofs and windows of residential and commercial buildings, but not to the Rainflo PVC-u gutters installed by some users.

DPI Plastics technical and product manager Renier Snyman notes that PVC-u boasts inherently strong impact characteristics, which makes the material highly resistant to storm damage.

“The company has been manufacturing PVC-u gutters and downpipes for more than 30 years and, over the years, we have developed a specialised formulation that includes additives to protect the gutters from ultraviolet (UV) attack.

“We also add impact modifiers to the formulation to enhance the impact resistance of the PVC-u and give it strength against adverse weather like heavy rain and hail. UV attack and impact are the two main aspects that can lead to damaged gutters and pipes,” he explains.

Snyman notes that, although the formulation of the pipes has improved with time, the design has remained the same.

“Formulation is something that can always be improved on, but we have found the perfect formula for our gutters and have kept it stable for a number of years,” he says.

Snyman points out that DPI Plastics installed Rainflo gutters and downpipes at its head office in Roodekop, Germiston, more than ten years ago, as part of the company’s commitment to testing its own products first-hand in the hail belt of Gauteng.

Further, the Rainflo gutters and fittings are installed using PVC solvent cement, which allows for easy installation, maintenance and cleaning.

“The solvent cement is applied to the fitting and the gutter and it welds them together. However, we suggest that our clients do not weld the downpipes, so that the pipes can be taken apart for easy cleaning, as they can become blocked with leaves and debris,” he says.

Snyman notes that the Rainflo gutters and downpipes have proved to be particularly popular along the coastal regions of South Africa, owing to the corrosion-resistant properties of PVC-u.

“Steel gutters and downpipes are prone to rust in coastal regions, and Rainflo serves as a suitable replacement system, as PVC-u is entirely rustproof,” he says.

However, Snyman says the products are not as popular in the inland areas.

“To counteract this challenge, we are increasing the marketing of the products in Gauteng and the surrounding areas, as well as spending more time on installation and product training. We started in August by exhibiting at the Plumbdrain Expo, in Johannesburg,” he notes.

Rainflo gutters and downpipes come standard in white, but can be painted any colour with exterior acrylic paint.

“The UV stabilisers create the white characteristics of the products, although adding coloured acrylic paint will not affect the UV guarantee in any way,” he says.

Rainflo products are SANS 11-accredited and gutters are available in D-shaped systems, with 80 mm square and round downpipes.

“The D-shaped gutter is suited to residential and commercial applications, where flow rates are not excessive, while the choice of downpipe shape is entirely for aesthetic purposes.

“It is, however, recommended that one downpipe is used for every 110 m2 of roof area to ensure the water is efficiently drained,” he says.

Snyman says the D-shape of the gutters allows them to carry more water than the traditional half-round-shaped gutters, resulting in fewer downpipes being needed.