Sand in PNW run-in shelters: how deep?

[cardinale]

PNW here, checking in from the mudpit. I’m having a guy come in with an excavator to dig out the muck in the run-ins, then add sand topped by mats (horses get fed in the shelters so want to minimize sand exposure there). The outside “apron” areas leading into the shelters will be scraped, then have sand added.

There used to be a great thread featuring Simkie’s run-in setup but it’s no longer accessible.

I’m keeping this low-tech and simple so just digging out the muck (which has old organic material which needs to be removed), then adding sand and, inside, mats.

Soil is clay or clay-adjacent (despite being listed on USDA’s soils map as sandy ).

Sand is nice, angular washed “river sand” (actually manufactured sand) that packs well per the materials yard.

So, those of you who’ve done this:

1. How deep of a layer of the existing muck would you dig down and remove? This time of year you won’t get to “dry.” Just get the loose, sloppy top layer off? Or dig down until firm (if not dry) soil?

2. How deep of a sand layer would you add? Too thin and it will just get sucked into the soil beneath. Is there a problem with “too deep”, i.e. leg strain from wallowing in sand, or does the sand pack and firm down enough that it can bear the weight of horses? I think it will pack down fine but is there such a thing as “too deep”?

Thanks

[endlessclimb]

Wherever you’re putting mats, I’d skip the sand and use screenings. Personally, I’d use screenings everywhere, and not use the sand - but at the very least, where you’re putting the mats should be packed pretty hard.

[cardinale]

@endlessclimb

Wherever you’re putting mats, I’d skip the sand and use screenings.

What size? I’m sure you’re right that it’s better and if I were staying long term I’d definitely do more but I’m probably putting the property on the market next summer so 1. just trying to get through this winter 2. avoiding adding anything rock-like in case the next owner wanted to do something different.

[endlessclimb]

3/8" minus.

[cardinale]

@endlessclimb

3/8" minus.

That’s not bad (too big) size-wise. I’ll ask the materials yard whether they have it. Thanks

[Simkie]

Oh god, don’t put sand under mats. At least not beach type sand. Angular sand, that locks together, would probably be okay. You want a firm surface. Screenings is better.

Are you talking about this thread? All the links to the pics still work, I think. I’m replacing the mats with 2" thick rough cut lumber this year.

Surfacing inside Run-In

 you: The original shed floor was this heavy gravel (class two?) with mats loose on top. The gravel was not something that compacted, so I removed a whole bunch an…

[cardinale]

@Simkie

Angular sand, that locks together,

Yeah, it’s angular sand (“washed river sand” around here). Materials yard said it’s what people use for riding arenas. But, the 3/8" screenings recommended by endlessclimb sound better. Contractor says we can rent a plate tamper for not much so some there will be some compaction.

Thanks for the link showing your thread is still accessible. I tried a link in another thread that didn’t work. Printed out the thread now!

Remains to be seen whether the mats will be too slippery (shed floors WILL be wet). I just want to keep hay off the sand/screenings.

[endlessclimb]

I have the “pebbled” ones, and they are not slick at all when wet.

Humane 4’x6’ 3/4" Speckled Utility Mat - EM502 | Blain’s Farm & Fleet

[cardinale]

None of the local gravel yards have 3/8" minus. They have 5/8" minus, 1/4" minus, and the washed river sand (angular).

endlessclimb, where did you get 3/8" minus?

[Xanthoria]

around here you’d ask for Class II base rock which has particles from 1" down to sand, compacts wonderfully, and drains great. Class II base rock is also known as Class 2 Road Base or Virgin Base, and often made of sand, gravel, and crushed stone, while recycled base rock is made from crushed concrete, asphalt, porcelain, brick, and other materials from torn down roadways, curbs, and gutters.

Its cheaper than a single species crushed rock usually, and is the perfect choice for drainage below paths, hard standing, erosion control etc

[sparkygrace]

We used packed 1/4 minus in our runs attached to the stalls. It worked well for a number of years, but since building the runs, we have put down rubber mats or plastic grid. The runs are 12’ x 16.’

Last year, we created a large dry lot for one horse, using a mix of washed sand and pea gravel. After thinking about it, we didn’t do a base. We put it right over grass and the footing has held up really well. It drains nicely. We are in the PNW and our soil is loamy clay, so we don’t have mud problem.

[Simkie]

@cardinale

Yeah, it’s angular sand (“washed river sand” around here).

Oh yeah, sorry, I see you did specify that. I was just having flashbacks from the thread title–there was beach sand or play sand or something under the mats in the stalls when we moved in, and it was absolutely miserable, haha.

I’ve found the term “screenings” pretty universal (although haven’t been on the west coast) so that might be something to ask for specifically. Are you talking to the quarry people, or someone who is reselling products from a local quarry? It’s better to go direct to the quarry, if you’ve connected to more of a middle man.

Putting in something that packs–which is 100% what you want–means that it WILL pack. You won’t be left with inches deep of loose product. It will compact. That layer will (hopefully) also keep your mud prone footing away from the surface & your horses.

I’d scrape everything off that you can and plan on 6 inches of rock. Compact the shit out of it with the tamper, drive over it with the tractor, etc.

And buy full trucks. The bulk of the price is the hauling, which you’re ponying up for regardless of how full the truck is. There’s ALWAYS a project where it’s nice to have a pile of screenings, if you really don’t use it all here.

Oh, I also don’t find wet mats slippery.

Best of luck!

[cardinale]

Thanks for the great info, Simkie. You are the run-in guru.

I’m dealing directly with the quarries, by phone so far but will go visit before ordering. I found one that does have 3/8" minus, just not on their website

So, the choices are 3/8" minus, 1/4" minus, and the angular sand. Looks like “screenings” might correspond here to the 3/8" minus and below sizes.

It does need to drain well, especially in the uncovered “aprons” leading up to the shelters. Do the screenings or equivalent around here pack so much that drainage isn’t good.

Might it be best to get 3/8" minus or 1/4" minus for inside the shelters, which will receive less moisture and benefit from compaction, and sand outside leading into the shelters? Also, would you put 3/8-1/4" minus where it comes in direct contact with hooves, or only under mats? Would the little pieces of rock be a problem or are they too small, or typically do they compact so much that it’s not a problem?

[NaturalSelection]

I have used limestone screenings, 3/8” minus and 3/4” minus (aka road base or Class 5 in the Midwest) in my drylot and run-in sheds. Have found that all these materials drain, but the superpower is that it packs and the water runs off (if sloped correctly) the coarser material packs better but the finer material is easier on barefoot horses. If I’m in a rush I don’t really bother to compact under the mats anymore, I just try to get it level and the horses do the compacting. Agree with others, if you’re using mats you want the material underneath to pack. We use mats around high traffic areas like the hay feeder, run-in shed, apron in front of shed and even a mat in front of the auto waterer; keeps everything from getting mucky bc you can fully remove organic material. It’s lovely.

[endlessclimb]

Nothing that packs really well and gives a good footing for horses will drain. You have to pitch it so the water runs off.

[Horsecrazy3]

I have 1/4minus in all my in and out paddocks and winter scarifice paddocks. It works just like 3/8 minus. I have used 1/2 minus as well. I live on the west coast of BC and have the same weather as PNW.

[Simkie]

@cardinale

Might it be best to get 3/8" minus or 1/4" minus for inside the shelters, which will receive less moisture and benefit from compaction, and sand outside leading into the shelters? Also, would you put 3/8-1/4" minus where it comes in direct contact with hooves, or only under mats? Would the little pieces of rock be a problem or are they too small, or typically do they compact so much that it’s not a problem?

Honestly, I’d go with whatever “minus” product is cheapest, and skip any type of “sand” product. No, those little rock pieces won’t cause any problems at all.

Once packed, it’s not an impervious layer, but water doesn’t just flow through it, either. Like endless mentions, you need to be sure to have a grade to allow water to run off.

And make sure you like where that water is going, too. Just as an example–when we moved in here, the runs off the barn were a mess. The previous owners didn’t clean, so they were just full of broken down poop. Gross. It held a ton of water, and the runs were an awful, muddy mess. It took awhile to get down to the actual hard surface, and when I finally did…I wound up with a crazy erosion issue in the pasture, because all the water that came off the “arena” ran into the runs. Which used to just hold that water, but I pulled off all the spongey organic material, and all the arena water and all the run water now ran off into the top part of the pasture and made a gully. The pasture was (of course) also in shit shape, and the erosion issue resolved once we got the grass healthy enough, but it was a bit of a surprise.

[cardinale]

OK, great, thanks everyone–the plan is coming together. 1/4 minus everywhere, since the nearest quarry has that.Will be graded appropriately. The pasture is pretty flat so the water that runs off the slightly elevated shelter area just creates shallow sheets of water that soak into the ground a few days after every heavy rain.

One more question: how deep should the guy with the excavator plan on digging down? The ground everywhere is so wet already that I don’t think he can get to “dry” readily. Yes, there is a mess in the shelters of old poop + hay. Should he just take off the loose, organic-laden layer? I don’t really know what we will find once he gets going. Will the ground firm up below the poop layer?

[Simkie]

@cardinale

Will the ground firm up below the poop layer?

That’s certainly the hope. Take off everything squishy. Hopefully you find hard pan–ground that is hard. Hard, like, you would have to work to get a shovel into it. Scrape off all the squishy stuff, replace with rock, and tada…no more mud. At least as long as you keep organics OFF. You’ll need to pick up all the poop and hay and whatever else winds up on it.

If you’ve got a really deep layer of top soil, just get to something firm and clean. The softer your base is, the more likely your rock will just mix will it, and disappear.

If you just keep digging, and can’t get to anything firm, can you pause and add some geotextile before bringing in the rock?

[cardinale]

I’ll go dig a hole with a shovel to find out what’s down there (before excavator arrives so we know what we’re dealing with).

Geotextile would be ideal as would grids which I would explore if staying long term but I’m probably moving this summer so trying to keep it simple and lower cost.