Where to Find Big Grate

We are looking at cutting a hole from the first story through to the second right in the wood room ceiling/ hallway floor and adding a fan while we are at it. Where can I find big grates-- bigger that 18x18 that are sturdy enough to walk on?

 

Big no no for fire code.

Gary

 

Did they outlaw them? When I was little everyone had these.

 

I'd like to go even bigger, Ray..

 

Oooh, louvred! That would be nice on the top floor.

 

RNT it (RedNeckTech) heavy duty expanded metal like catwalk material.

 

Might be okay with a fire damper on it. It closes it off if a fusible link gets to hot.

Gary

 

Holychit ! I've been scarfing those out of dumpsters and cutting them in half. Got a hole in my furnace grate . Been laying a half over top of my grate and making do. A half has been lasting a season.
Might have to sell a couple and buy factory grates. Was dreading buying new ones at $250 pair. May not be so painful if'n I sell a couple of those vent grates .