print bed insulation

[neverlift]

well i was on mcmaster looking for some tappered studs for a control arm project on my drift car when i started thinking about insulation for the heat bed i came across calcium silicate insulation apparently what they use in ovens i can get a 12x12 sheet for around 14.00 but the thinest it comes is in 1/2" is this to thick to use, it looks like a good option considering its rated to withstand 1700*f
here is a link to mcmaster
http://www.mcmaster.com/#thermal-insulation/=wpg06g

[AbuMaia]

I use a 5mm thick sheet of cork under my heated bed.