Workshop Floor

Hello fellow Permies!

For my first post I am going to give all of you a scenario where I would like to replace a broken not so level concrete floor in an old farm garage with an earthen floor of some type. Probably a cob floor as I have a little experience making and using cob.
The building is a 24x24ft old garage. Possibly as old as the house which is approximately 100+ years old as I've been told. The inside of the garage must have had rooms in it as there is foundations for walls that have been removed. (pic provided)
I plan on using this space as Blacksmith workshop/man cave.

My experience level is quite low with A: Removing a concrete floor (none) and B: Using cob. I've had a quick half day class on making and using Cob while taking a PDC in Oregon.
So my thinking is that I would tear out the concrete and level the ground then put in the cob and then level it out?
I've added some pics to help you guys get an idea.

I will post more pics when I clean out the garage and give all of you wonderful individuals a better idea!

Thank you very much for any input!

Here are some better angles! I apologize for the first few pics!

More pics

I have an alternative suggestion. Polish and grind the existing surface down to a new flat level and seal it. Dale posted a series of photos of him doing just that restoring an old concrete floor and it looked awesome. Grinding the floor is a matter of a few days of work with a hired grinder. Removing the concrete and cobbing it could take months, and I doubt you would end up with a floor durable enough to cope with blacksmithing.

Found it: Concrete floor resurfacing

Thanks for the quick reply and suggestion Michael!

I like your idea, however I have a feeling that the concrete is much too cracked and broken in most areas of the garage. The concrete that Dale ground down looked quite intact.

Why would it take so long for to remove the concrete and put in a cob floor? Also I was under the impression Cob is relatively durable. The anvil will be on a heavy base full of sand, the majority of the energy will be absorbed by the steel, anvil, and base. I won't be doing any heavy work just hand work like knife making and so on.

First off, Welcome to Permies, Nick.

Great first posts. My suggestion would be to combine Michael's idea of grinding the surface flat, seal the cracks with some grouting material and then use your cob as the floor sealant. This would considerably cut down the amount of work needed to renovate the floor and give you a fairly solid base for your blacksmithing activities. Even though you only plan to do light work, this will still give your anvil a solid base to rest on and be very stable.

Just my two cents. But I know what a bear it can be to bust up old concrete, even with a jackhammer.

Yes indeed...Welcome Nick!

Great post project to share...If I may offer any support beyond these few words do let me know.

First, I REALLY do not like concrete...especially as a work surface to stand on! There is research about the issues with the effects to the back, body and related as a poor living, working surface for human ergonomics not being compatible with this material...

Never the less...we often must plow with the horse we have...not the one we want...So, there are times to make do and "re-purpose."

From my perspective of your project and have some experience in multiple flooring modalities...I think I can say, with some confidence, I would not recommend a cob floor for a Blacksmiths shop, or any other "high impact" work area. Additionally, as a comparative from inside my head and thinking of examples I have seen and been part of, the logistics of removing this and cobing...would be daunting compared to Dale's approach as Michael C. has suggested. I "regrind/bush" stone all the time (much harder material than concrete) and with a rented industrial machine, I think you could even call this process "fast."

My next possible suggestion would be to remove the concrete as you desire (or leave in place??) and "float" a traditional wood plank floor. These can be very enduring, and are not the fire hazard many suggest they are...even in a Blacksmiths shop, which I have been part of a few of those...A link to some possibilities in wood can be found at 청마루 (Cheongmaru) Floor Systems.

Next would be a combination...as already suggested...of the current concrete in situ...ground level, with the cracks and fissures filled and leveled with either a limecrete and/or Tataki 三和土 method. Info on this can be found at:

Tataki 三和土

Limecrete Flooring...

Good luck with your project...

Thank you all for the warm welcomes and the great info!

I'm starting to like the idea of grinding down what its there to level and then filling in the cracks and then putting on some sort of earthen floor to seal it. The limecrete is really neat! The wood is also a wonderful design. I'm looking for speed and cost effectiveness as I'm hoping to have this done before winter to enjoy some blacksmithing to keep me warm...err hot really.

I'm going to look into renting a grinding machine and see the cost of some sort of grout to fill in the cracks with.

I did some probing into a badly damaged part of the concrete and took some pics.