Crack mat or cement board

[Berts81]

Got a 100m2 floor to do in 900x900 , floor is chipboard with underfloor heating below, floor is very sturdy no deflection, I've always thought dura base matting more for screed and cement boards for wooden floors.
Which is best option to go with for belt and braces

 

[Tile Marble Granite]

Dura Base Matting is a lot better than cement boards, it is lighter and anti-crack

 

[Dan]

In the UK it'd be...

Chipboard needs replacing with marine ply 19mm minimum. Screwed at 300mm centres, noggins need adding under the ply where 300mm meets nothing underneath. It really needs strengthening first even with a matting down given there's UFH underneath. I assume it's Water UFH?

However in the USA TMG would be the guy. 🙂