firebrick -- low temp uses

I couldn't find any info online.
I have common burnt clay red brick. I also have regular hard firebrick (not the insulating or soft type).
Anyone know how the hard firebrick holds up and performs compared to (and would be alongside) common burnt clay brick, with regards to being laid as:
-interior floors--probably set on tamped road base. Durability?

-laid up as interior wall (load bearing not plastered trombe wall). Similar thermal performance?

-exterior siding/wall (most days see freeze thaw). Comparative Spalling resistance when well lime washed? Minor overhanging eve

The firebrick on hand are heavier, more dense, seemingly less porous than the common brick, and when I rub the two types together, the dust is red. More abrasion resistant.

Anything that I should know before I lay them up together? I don't know who to ask.

And I'll save some firebrick for kiln, forge, other people's stoves/ovens. I know their High temp value.

Thanks

It sounds like you plan to mix the two types of brick in a floor, Yes?

The first thing to determine for such a project would be brick thickness, they need to be close to the same so you don't end up with base issues.

Another thing to keep in mind is that firebricks use a whole different formulation of mortar than those red bricks will use.
That is an incompatibility issue that will not go away, and is something you really need to check into in depth.

I don't see any issues with using the type 1 firebricks for flooring all by themselves. you might want to use the red bricks for a border or interlacing design part of the floor instead of something like a checkerboard or herringbone type pattern.

Thanks Redhawk.
Yeah same standard dimensions.
I know that high temp usage on firebrick calls for fireclay and related. I used regular clay mortar on my rocket no problems fired hard. I Adobe grouted my concrete and endgrain (laid basket weave) pavers in the dome--and no one arrested me. The grout is holding up fine I think because I forced lots of thinned linseed in it, all topped with oil, a little spar resin I had, and melted beeswax. Moppable.
I reckon it'd be fine with mixing these bricks In the additions. I'm thinking same floor treatment: Adobe grout maybe with lime, and then All topped with same recipe. These firebrick are pretty dense though, I'll have to really thin the oil and not let it puddle sticky.
For interior wall mortar I'm thinking 1:1 cement lime on the binder. Its holding massive weight.
I'm not sure about exterior application of firebrick. And my red may be too soft and porous for anything non sacrificial outside.

Nice! and a big pilamayaye(thank you) to you kola(friend), I didn't know of that method. I will have to give that a try.