A new age for dry fixing

Andrew Cross of Klober addresses the gap in quality and performance of dry fix systems and how a new British Standard could help specifiers navigate the growing market

With housing associations and local authorities investing significant sums to ensure the long-term thermal efficiency and build quality of their properties, greater attention is being paid to design life rather than the lowest tendered cost. By contrast, some private sector landlords have been slower to adopt such changes in the procurement process, which often means the cost of maintenance and remedial works 20 years down the line could be significant.

Understandably, many consider that relying heavily on a ‘commodity approach’ rarely leads to cost-effective results. Part of that problem stems from performance comparisons that are based purely on third party accreditation, such as that provided by the British Board of Agrément.

However, even the most cursory examination of certificates can reveal quite how marked the product variation can be. This is because few check that manufacturers of products sold on price can get away with selling them as ‘like-for-like’. Despite the saying that “there is hardly anything that someone can’t make a little worse and sell a little cheaper”, many companies are clearly prepared to let this be their primary strategy in pursuit of quick market share.

Choice aplenty – but watch what you pay for

The roofing sector is a case in point, with products such as dry fixing accessories being offered at increasingly lower prices as a means to compete with market-established brands.

For those involved in social housing provision, roofing accessories offer benefits out of all proportion to their cost. Dry ridge, hip and verge accessories have been used extensively for long enough to demonstrate proof of performance.

The use of mortar however had become increasingly problematic, to the point where the National House Building Council and the British Standards Institution felt they had to make additional mechanical fixing mandatory. Indeed, the level of claims had reached the point where insurance underwriters thought their widespread incidence and cost had become unsustainable.

While problems associated with the use of poor quality dry fixing accessories may not appear as quickly as those related to the use of mortar, there had been instances where ‘failure’ within a fraction of the solution’s projected design life have been documented.

Setting a standard

As an increasing number of new dry fixing products have been launched to the market in the past five years, the absence of a British Standard has made choice increasingly difficult for contractors. Despite being supported by little more than promises about performance, the attraction of low cost products remains irresistible for many specifiers and roofing merchants. Factors such as durability, colour retention, dimensional stability and weathertightness can vary, so the imminent publication of the new standard – BS 8612 – really cannot come too soon.

Designed to provide a benchmark for quality and place a requirement for manufacturers to publish specific product performance data, it can only be hoped that the standard will finally put pressure on those companies whose products would, in essence, create a liability for the customer, rather than offer long-term performance.

The devil’s in the detail

For building owners and facility managers, dry fixing represents a very simple and inexpensive way to ensure a roof will remain without problems. It has been the preferred method for such repairs in Scotland for more than 15 years, but despite the greater experience north of the border, product comparison there is similarly problematic.

However, some features, such as the backing adhesive used on a ridge or hip roll, can be checked with relative ease. For example, only the highest-performing products bond securely to dusty surfaces, a butyl rubber-backing providing instant adhesion and weatherproofing protection. Those manufacturers, whose products use such material, would typically demonstrate that in published information. However, it is important to emphasise that anything less effective could be at a risk of early failure through the effects of adverse weather conditions during the curing process.

The new standard has been designed to prevent this and is likely to cover product features that are currently given little consideration, such as fixings and the base material from which dry verge and ridge unions are made.

And while the devil is always in the detail, if facility managers are looking to achieve life expectancies of up to 20 or 30 years, then that ‘detail’ could be crucial.

Andrew Cross is marketing manager at Klober