Hi,

I am building a 12 x 16 shed(first time). I have railroad ties and put 3/4 clean stone above ground as can be seen in the pic. I compacted the stone using a plate compactor. My ground slopes from left to right and front to back, so it is difficult to get it leveled. Also, the 6 x 6 skids are not perfectly straight, so that doesn't help either.

As of now, both of the skids are almost leveled individually. They are off by about 1/4 inch in some spots and 1/8 in other spots.

However, when I tried to level the skids to each other by putting a 2 x 4 and a level across both of them, they are not level. They are off by about 1/2 inch in some places. It just seems very difficult to level them individually and also as a pair. I plan on putting a 2 x 6 floor with header joists and floor joists. So, can I shim between the skids and the header/floor joists? This would make life easier, because even if I level the skids, the 2 x 6 will not be 100% straight and would require some shimming anyways. If this works, what should I use for shims? Also, shimming would raise part of the joists of the skid, so should I cover all those gaps with wood shims or shingles?

If the above is not a good idea, can I put concrete pavers underneath the skid to get it leveled? My only worry with this is that the pavers can sink into the gravel and also that the skid will be off the ground and in the air in a few places. I can put gravel underneath it, but it will be loose and will eventually fall out.

Also, if anybody has any other options, it would be very helpful. Sorry the detailed post, but I am just confused on what to do.

Thanks,
John M.

 

Hi John, sheds are fun, so many will jump in here to help and I'll let them address the leveling question. My first concern would be the gravel swimming pool. If the shed is going to rest on the skids, inside the perimeter of the RR ties, then how is the rain off the shed roof going to drain from the gravel area. It may be fine, depending upon the soil beneath, but it might also fill and drain over the top at their lowest point. Just a thought for all to consider.

What is going inside this shed, as 2x6's can be on the small side?

Bud

 

Thanks Bud for responding. The soil underneath the gravel is very permeable, so I think it should be ok in that front. I am going to put lawn tractor(600 lbs) and things like aerator, dump cart, snow blower(200 lbs), etc...

I made a mistake by listing it as 2 x 6. I meant 2 x 8. Sorry about that. Are 2 x 8 fine?

 

I assume the skids are set in a bit, say a foot or so, so the 12' width would yield a 10' span, approximately. 2 x 8' are better, but i'll let the more experienced shed pros do the span calculations.

A friend of mine built a walkway with 2x4 edging and filled the path with compacted gravel. Only problem was, it was directly on clay and took days to dry enough to walk on. Was probably still wet below the surface.

Are those skids pressure treated?

Bud

 

The base is almost 16 by 20 ft. The 6 x 6 skids are 16 ft long. And yes they are pressure treated.

 

Hope your planning on more skids. Going to need at least 4 for a shed that size. If not it's going to sag in the middle.

 

Thats what I thought also, but the design that I bought from just-sheds said, that no only 2 are needed. I even emailed them to confirm and they said, that only 2 are required. Should I add a couple more to be on the safe side?

 

I constructed a foundation like yours, adding the gravel in layers and compacting edge layer individually. My shed was built on this by pros, who did absolutely no leveling after they checked my grade and said it was as good as they had ever seen. The floor inside the shed is almost perfectly level. But here's the BIG difference. The owner of the shed company told me they had been using 4x6 skids similar to your 6x6, but had too much trouble getting straight ones (too much warping and twisting). He said they just had to return or throw out too many of them. They now construct their own skids by nailing three kiln-dried 2x6 together. I check them, and they're very straight. Also, here's another consideration. If your 6x6 beams are not kiln-dried, they will warp over time.

 

I would consider using those RR ties instead since they are almost indestructible and will probably outlast the shed!