This term refers to the roof structure that is insulated AT or ABOVE the pitched rafter level (as opposed to the horizontal ceiling joist level). Warm roofing is usually found forming part of a complete insulating envelope that is designed to encompass the building’s main structure.
Buildings need to be thermally efficient and the performance requirements for these buildings are constantly increasing. Applying a single, uninterrupted layer of sealed above-rafter insulation helps to meet stricter u-value targets. The lowered thermal conductivity delivers a reduction in heating costs and also lowers emissions.
Lost spaces can easily be converted to living space without increasing plot size and all services in that area will be protected from freezing without the need for extra ventilation. Condensation is alleviated by the warm roof structure, which locates the dew-point further out of the building.
We recommend Super-7™ warm roof fixings. These helical fasteners are self-tapping and securely fix counter battens to rafters, sandwiching the insulation between. Helical Super-7™ nails, manufactured by Thor, are engineered with the most precise pitch accuracy, easing driving and reducing the chance of buckling.
The Super-7™ Guide Tool is designed to overcome skew fastening deficiencies and improve build quality. The spiral nail is guided through a layer of insulation, vertically into the central part of the rafter, giving a highly professional result. The single layer process replaces the need for dual-layer systems, which are less efficient and more labour intensive to install (up to 66% less nailing is required).
This depends on the building’s individual details, as well as on the location of the building and its consequent exposure level. Many loads must be taken into consideration, such as compressive (from roof weight and possibility of snow), tensile (from wind suction) and sliding (from a combination of compressive load, roof angle and insulation depth. Working out the right number of fixings can be easily done with the HeliCalc™ software co-sponsored by Twistfix and available on our website.
The software will select appropriate fixing length and density using BRE-approved design methods, calculating to take wind and snow loads into account to adhere to BS6399 Part 2 & Part 3. National Annexes to Eurocodes 0 and 5 apply partial safety factors in respect of timber connections, dead loads, wind loads and snow loads. Please note that all results from this software apply to genuine Thor Super-7 fixings.
Product: | Super-7™ Warm Roof Batten Fixing |
Lengths: | 130mm - 240mm in 10mm increments |
Diameter: | 7mm |
Cross Sectional Area: | 9.9mm2 |
Ultimate Tensile Strength: | 1025-1225N/mm2 |
Material: | Austenitic Stainless steel - (304) |
Pitch Deviation on Tie: | < 0.5%* |
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