Concerned by water tightness failures in alternate roofing underlays, DuPont Tyvek instigated an independent field test to examine the ‘real world’ performance of its systems.
After hearing reports of alternate vapour-open roofing underlays leaking, DuPont Tyvek issued an investigation into the ‘real world’ performance of these systems.
Martin Peifer, an independent expert of Steildach-Technik GmbH, was contracted to collect underlay samples from 30 different roofs.
These roofing underlays were exposed to rigorous water tightness tests at the Kiwa GmbH TBU laboratory; the tests were designed to examine how each underlay has aged in the ‘real world’.
Whilst the ageing process can have a positive impact on vapour diffusion, it can adversely affect an underlay’s water shedding function should the primary covering fail. In stormier weather, this is a common occurrence.
Each sample was subjected to a 20cm water column for two hours. Experts assessed whether any leakage had occurred; if so, how much, over what surface area and how quickly. The EN13859-1&2 classification system for water tightness was used to determine how well each roofing underlay endured water after 5 to 10 years in situ.
Following the tests, 13 out of the 17 Tyvek underlays examined were declared watertight, after more than 20 years in a roof. The Tyvek samples were significantly older than the other installed products, demonstrating their durability.
Meanwhile, 2 out of the 7 coated roofing underlays tested could be declared watertight after less than 10 years; none of the multi-layer microporous based roofing underlays achieved water tightness.
DuPont Tyvek argues that a roofing underlay’s primary quality, in terms of longevity, is water tightness – underlays which fail to provide this are putting property and insurance at risk.
The company believes that current building and industry codes, with their focus on mechanical stress, are misleading. Homeowners are more likely to benefit from long-term water hold out; assessment methods still lag behind in evaluating this.
DuPont Protection Solutions
Bristol & Bath Science Park
General enquiries: 01275 337667 (Option 2)
Technical: 01275 337667 (Option 1)
In this article from FEIN, Jasper, a young self-employed joiner, discusses his work, his views on buying tools and his thoughts of FEIN’s newly launched value pack range, focusing on the Best of Flooring set.Posted in Articles, Building Industry News, Hand Tools, Innovations & New Products, Plant, Equipment and Hire, Posts, Power Tools, Research & Materials Testing
Dulux Trade celebrates success after winning big at the 30th annual Painting and Decorating Association awards last week, taking home a grand total of four accolades.Posted in Articles, Awards, Building Industry Events, Building Industry News, Building Products & Structures, Interiors, Paints, Paints, Coatings & Finishes, Posts, Retrofit & Renovation
Derrick McFarland, MD at Keystone Lintels, discusses the importance of quality testing and third party certification when specifying structural products.Posted in Articles, Building Industry News, Building Products & Structures, Building Regulations & Accreditations, Building Systems, Canopies, Entrances & Column Casings, Doors, Facades, Innovations & New Products, Posts, Research & Materials Testing, Retrofit & Renovation, Steel and Structural Frames, Walls
This article from Contour Heating looks at how school attendance can be improved by reducing the spread of illness, through LST Radiators.Posted in Articles, Building Industry News, Building Services, Health & Safety, Heating Systems, Controls and Management, Heating, Ventilation and Air Conditioning - HVAC, Interiors, Posts, Research & Materials Testing