So my husband and I are planning to build a single stall barn with a storage area. Dimensions are 12x20, so the stall area would be 12x14. The structure will be 12’ high at the front and at the back/lowest pitch it will be 8’. It will be a run in style, so our horse can go in and out at leisure unless the weather is really bad. We are having a hard time deciding on the best way to go about the floor system. At the moment we plan to do boards as a subfloor with stall mats on top. The floor joists and frame will all sit on concrete posts or cement blocks. Do I still need to have some sort of drainage system underneath the subfloor? And this might be a stupid question, but what is the likelihood a horse will not step up into the threshold of this shelter? I’d also love to hear from those of you who have built similar structures, and what your materials/cost to build ran. Thanks all!
How high will the structure sit above the ground? Is there a reason it’s going to be a shed with wood flooring instead of a run in style directly on the ground? (You’d then use gravel and mats to create a stall floor).
I’m worried a run in wouldn’t be a good year round option. We get a lot of snow and cold and with an unshod horse I assumed a level, dry floor was the best and easiest way to go about it and avoid future health issues. I was initially concerned about the level of maintenance with a dirt or run in floor. Wouldn’t it constantly need to be leveled out? And be an issue of wetness/muck in some seasons? This will be a 4 season shelter so I want it to be as efficient and sensible as possible!
So say I did a run in style. If I dug 3" down and did crushed gravel, tramped it down and added some cement dusting. Then mats on top. Is that a sufficient year round floor?
I don’t have a run in, but do have a 12x36 overhang off my barn, so very similar to your set up. It sits about 6" above my paddock. It has a base of dirt topped with mats. I used RR ties to edge it so horses step up a bit to use it. No issues there. We get a lot of wind and rain, and it generally stays pretty dry as it faces away from prevailing wind but can get some when we get a storm out of the west. The front edge doesn’t have mats, so it does get a bit wet but it’s so packed it doesn’t get muddy. My paddock is all fine gravel so mud free which helps tremendously. Snow does blow in, and I simply shovel or sweep it out as necessary.
I’d worry about rot with wood flooring, even if you used pressure treated. That’s maintenance I don’t need. I’ve had to add dirt/gravel to mine once in 15 years and that was because we added a few inches of gravel to the paddock and I redid my RR ties.
Thanks for your input, that’s helps tremendously! So in your experience, the dirt underneath the mats really doesnt need to be leveled regularly? I keep thinking of the gravel shifting with drainage etc. and needing to be leveled out every few weeks, but I could just not be imagining it properly. I’ve never had to consider a floor before with previous animal shelters. Wood definitely poses an issue of rot. I’d love to do a simple earth floor base but my hold up is probably my lack of knowledge and experience with that sort of thing lol! I assumed the earth floor was a greater upkeep as the gravel would shift with the seasons changing/frost etc.
You need to dig deeper - my excavator did 9" then 6" gravel, then 3" stonedust on top.
Same for the attached indoor except sand in place of the stonedust.
That is the flooring in my stalls & aisleway for my center-aisle barn.
Built 15yrs ago next month & stall floors remain level (in spite of some tunneling by vermin).
Barn acts as a run-in since stall doors to paddock remain open 24/7/365.
Last Fall I added a sill (2X4 composite decking) to the back of each stall - preventing them from dragging bedding out & making a swamp in back of the stalls.
It has worked pretty good & nobody has an issue stepping over it.
Aisle feels like concrete to me, can be swept & even hosed, but horses still leave shallow hoofprints - even the mini - so it has some cush for them.
I do not use mats in my stalls, just pelleted bedding on top the compacted stonedust.
Drains great, stalls never reek of urine, even now when frigid Midwest has frozen some of the pee spots so there will be no digging them completely out until we get a thaw.
Horses still go flat to sleep - as evidenced by a coating of pellet dust all along one side = BedHead 
“Mats” in the aisle are re-purposed rubber roofing (ice dam?) I got for free from one of the builders when barn was put up.
Gives shoer/vet/me a clean & dry place to work.
I used the same stuff as mats in stalls, but it only lasted about 5yrs before hooves & muckfork tore it up.
Awesome thanks for your input! Is this method also more cost efficient? I’m not sure what gravel or stone dust go for around here but I think that sounds like the best route for us.
{Shrugs} since this is the only method I considered & it was so long ago, all I can say is cheaper than concrete.
Ours has a cement foundation all around - not just the posts. Cement goes down into the dirt and is raised around the sides. Water does not seep in there. We have mats on dirt. If I were doing it over - I’d do mats on gravel or dg. I might do that anyway. These are heavy, heavy mats and they don’t shift much. You might check on mat dimensions before you do the 12x14 vs a 12x12 or 12x16. I don’t know if they come in widths that let you do a 12x14. Ours is a 10-stall - it functions like a run-in too as the doors are open 24/7/365. Doors on two sides of the stall. Window to feed bin. 12’ overhang (can’t tell you how much I love that). I can’t see any long term function to a wood floor. Weight alone would crack it over time.
The footing for your size would be fairly cheap. I can get 12 yards (10 tons or so) of screenings for $300 delivered. If you compact it and perhaps put in an edge like 4x4 or RR ties your base won’t move. Will this shelter be in a field or sacrificing area? Will that area become muddy as horse moves back and forth out of shelter? Will you feed in there?
I just did the math and it would be roughly 9 tons of gravel for a 9" depth for 12x20. I can get 3/4" crushed gravel for $7 a ton. That’s roughly $60 to fill gravel. What am I looking for for the stone dust on top? is that also known as “crushed stone?” And could I add dry cement to this crushed stone as a layer underneath the mats? I’m sorry if I sound ignorant or I’m over complicating, we are doing this ourselves and I’m trying to figure out the best way to go about this so I don’t have reoccurring issues.
I would consider pouring foundation but it’s expensive and seems like it would be overkill for this simple structure. Especially since we don’t plan on living at our current residence long term.
For both high end and budget solutions, I would recommend installing a base, tamping it down (compacting it) until it was completely level and putting mats on top. Railroad ties or pressure treated 4x4’s that are sunk in the ground and used to edge the front opening, thereby keeping the mats and base in place are ideal.
Make sure your base is level. Make sure your mats fit without gaps. Make sure you “edge” the front opening with treated lumber to keep everything in place and you’ll do fine.
No need for concrete. Just do a gravel base, rent a tamper and get it firm. I’d skip stone dust and use 3/4 minus stone. Top with mats and definitely use a barrier of rr ties or treated 4x4s to create a frame. It’s very doable and will hold up for years.
[QUOTE=HouseKat;n10334986. What am I looking for for the stone dust on top? is
I would consider pouring foundation but it’s expensive and seems like it would be overkill for this simple structure. Especially since we don’t plan on living at our current residence long term. [/QUOTE]
Stonedust seems to have a variety of local names.
What I am referring to is like beach sand with very large grains, until it is tamped or gets packed down it has a feel underfoot very much like sand. But the rough edges cause it to lock into place over time.
I wouldn’t bother with adding cement as then you are compromising the ability to drain well.
What size compactor do I need to rent? They’ve got a 1200 lb one and there are smaller options as well?
I think the key to keeping the floor dry would be location…higher up and drainage. Also the entry should be hardened and maybe have a mat.
