Hearth Extension question

[clancya]

I recently purchased this house with Napoleon 1402 insert. The inspector said I should add a hearth extension for safety, which I agree. Looking at continuing the concrete that is there with some sort of stone or paver. I plan on placing the extension 16" out from the face and 8" past the sides of the box. It will be placed over the wood flooring. I have read that I should place some fire rated materials beneath the stone to get the R value up to .80 . Also will be using a fire rated caulk for any joint. I have included a pic of the fireplace and specs from manual.

Can I just place this directly on the wood floor without permanently affixing it? Anything I forgot?



From the manual.

 

[begreen]

They make heartpad extensions of 18" x 48" for just this situation.
This one would work

https://www.efireplacestore.com/sbi-ac02785.html

or https://www.woodlanddirect.com/hy-c-18-x-48-type-2-hearth-extender---black/177072.html
or fancier

https://www.wayfair.com/home-improvement/pdp/tretco-extension-fire-back-hths1008.html

 

[clancya]

@begreen Thanks, I have seen those, but I plan on trying to match the concrete that is there. The fancier one might be okay but looks like the darker grey is out of stock.

 

[begreen]

These were just examples. There are several manufacturers, just be sure it has at least an R=1.1 rating.
Hearth Classics has been making them for a long time.

Hearth Pads - Natural Choice for Home and Hearth - Hearth Classics

Hearth Classics Hearth Products stone and ceramic tiles hearth pads are the ideal foundation for freestanding gas, wood, pellet, corn, coal or oil stoves.

www.hearthclassics.com