Providing adequate fire protection between different floor levels in multi-occupancy buildings is made more challenging where existing ceilings cannot be removed. An effective solution is offered in the form of Intudeck, a Firetherm product, comprising high-density mineral wool boards with a fire and smoke resistant endothermic coating on the upper face.
Available in 1200 x 600 x 70mm, Intudeck is quick and easy to install, whilst applying minimal load to the ceiling joists. The product can be cut to fit on-site and compressed and bonded between the floor joists. A 10mm bead of Intumastic sealant applied along the side of the joists, 35mm up from the base to define the end location and allow for cable runs in lighting circuits. Once all sections of Intudeck have been pushed into position at high compression using a board to spread the force, a further 5mm bead of Intumastic is applied around the perimeter of each bay and along the butt joints to ensure a smoke and air seal is maintained.
Intudeck is often preferred where occupancy prevents a downstairs ceiling being removed, or when contractors do not want to take down ornate lath-and-plaster ceilings. Work begins by lifting floorboards to gain access and thoroughly cleaning the void space, including removing dust from the sides of the joists to achieve a good bond.
Not only does Intudeck offer up to 90 minutes integrity and insulation under BS 476 Parts 20 / 22, fitted between 6” x 2” (160 x 50mm) joists, but it has also been load-tested to BS/EN 1365-2 standards to demonstrate the installed products’ integrity. As a loaded system tested for use with 7” x 2” (196 x 45mm) joists robust details to suit the span.
Tremco-illbruck is believed to be the only manufacturer to have completed such testing. They have done so on solid timber joists suited to load vs span requirements, typical of the sizes found in older properties. Intudeck could also be used on non load-bearing joisted ceiling systems with beams of a significantly smaller size. The company further offers a full range of intumescent collars and other products for fire-stopping around existing service penetrations.
This highlights the practical nature of the Intudeck solution with existing floor constructions being easily assessed to judge the spanning capabilities. Installed in accordance with Firetherm’s guidance, Intudeck will also achieve a 42 dB sound reduction between floors and a thermal resistance of 0.038 W/Mk.
In an effort to assist surveyors, fire consultants and Building Control Officers, Firetherm has additionally incorporated its Optifire, optical tracer technology into the fireproof coating of Intudeck batts and mastic. By shining an ultra-violet light onto the top surface of the batts a confirmatory blue glow is immediately generated.
A comprehensive product data sheet is available from Firetherm, along with specification advice and technical assistance where required.