22mm UFH pre routed chipboard flooring

[Scar Glamour]

Hi there. I'm planning a renovation and installing UFH in the first floor bedrooms which are suspended joist floors - approx 18" or 460mm centres (approx 410mm span) joists. I'm going to lift the exsiting floorboards, clear out the voids, batten the sides of the joists to support rigid PIR boards to sit flush with tops of joists, then oversheet with the prerouted 22mm P5 chipboard flooring (2400mm x 600mm) which you then lay the ufh pipework in, then lay 10mm laminate over (with a 2mm cushion layer between).

HeatBoard ONE MAX PLUS - 2400x600mm - all in one 22mm Foiled & Grooved Chipboard Panel - High Heat Output | The Floor Heating Warehouse

High Output - Easy Lay Foiled Chipboard Floor Deck, Underfloor Heating System for Joisted Floors Features: 22mm Flooring Grade Tongue & Groove Interlocking Chipboard Panels for 12mm Pipe Floor Board & Underfloor Heating Combined Panel Specification: Each Board: 4 Grooves at 150mm Centres for...

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Question is, in order to get the laminate orientated correctly (lengths pointing to the windows) the pipework needs to run at 90deg to the laminate, meaning the 22mm chipboard will need to run along the length of the joists. This means one long side of the chipboard will be unsupported along the length. I've read the short ends can fly between joists, but what about the long edges? Planning on gluing and screwing as standard, but don't fancy nogging / dwanging every second joist span. Bear in mind that with the 25mm battens supporting the PIR, the clear span would be about 360mm. Is gluing the long edges enough to stop any bounce?

Any thoughts?