Building a small shed

[Kevin]

I'm putting together my gameplan for building (actually rebuilding) a small shed for the yard. It's going to be a 10' x 16' saltbox. I have a couple of questions I was hoping someone could help me with. First, on of the 16' walls will be partially below grade (the shed is going to be built into a small slope) so I plan to use pressure treated sheathing on that part, as well as applying an additional wood preservative (cuprinol or other product?). Should I also apply another barrier such as plastic sheeting or typar? And would I gain anything by also using pressure treated studs to build the walls that are below grade? My initial thought was to build a 3 or

4' knee wall on the offending side and then build another wall section from regular studs to attach to the top. The question that arrises with method two, how do I frame the windows in. Assuming there would be a double sill/header where the knee wall meets the upper wall section would I need additional jack studs in the knee wall, under the window edges?

Second area of concern is the "foundation". The floor of the shed will be crushed stone. I plan to dig a trench under footprint and put in 8" to 10" of crushed stone with drain pipe just inside the walls, then lay 6x6 PT timbers surrounded by crushed stone with the tops at grade of the finished floor and then build on top of those (PT sill plates would be nailed to the

6x6 posts. Does this seem like a horrible idea? The current construction (not my project) utilized 4x4 posts installed at the corners of the shed. They were put in at least 2' into the ground (I haven't dug any further to see just how deep they were) and they continued up the the top of the wall of the shed (existing shed is gambrel style so the wall is only 4' above ground before the roof angle). Does this seem like a better idea or even an acceptable method? to be honest, despite all the problems with the current shed, It does seem that the 4 corners are still square.

Thanks in advance for any help and advice.

Kevin

[Steve Barker DLT]

How much under grade? Personally, I think I'd build a concrete block 'wall' for the wall that's under grade. Never have to worry about it then. Probably wouldn't cost any more than the PT lumber.

s

[Kevin]

Only about 2 1/2' is below grade which seems like it might be a bit of work to do concrete block for such a small area.

[Dioclese]

All things being equal, seems the 2 side walls will also have some below grade as well.

Some obvious landscaping, on the side where the high slope is, may prevent or reduce eventual soil and plant debris buildup. Ideally, will cause runoff to go around the shed.

Insects and other small varmints can be concern on such a floor you've described.

[DanG]

I wouldn't put any part of a wood framed or wood sided structure below grade. Choices could include a retaining wall to keep the high ground back away from the structure a few feet with plenty of drainage under or around the structure or creating a concrete or masonry stem wall.

[dpb]

If you're going to do it, why not do it right? Pour a footer below frost line, lay a block wall to above grade and build on that w/ conventional framing and floor joists. Or a variety of the same or level the area...

What you're talking of doing is simply silly to waste the effort and $$ unless you're 70+ and don't care that it will fail (which it will...)

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[tbasc]

le of

Why not work the land on the up-hill sides of the building?

2 1/2 inches shouldn't take a lot of work. I would consider a curtain drain / french drain on three sides with discharge down-slope. T

[dpb]

[e-mail] wrote: ...

...

The reply was 2-1/2' (not ")...

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[Steve Barker DLT]

well 4 courses of block the length of the building. Ya, it would probably take 3 hours or so.

s

[Steve Barker DLT]

" = inches

' = FEET

re read

Why not work the land on the up-hill sides of the building?

2 1/2 inches shouldn't take a lot of work. I would consider a curtain drain / french drain on three sides with discharge down-slope. T

[Dioclese]

Maybe I overlooked something. I saw no indication of location that would indicate a frostline need regarding footers.

Irregardless, he could put the entire shed with a wooden floor on pier and beam above ground level. Alleviating all the potential factors of soil intrusion, insects, varmints, and ground freezing degradation.

[dpb]

Dioclese wrote: ...

And did you see an indication the location was where there is no frost line, either??? :(

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[HerHusband]

Pressure treated wood will still rot, it just takes longer.

If you want the shed to sit right in the slope of the land, you should install a proper concrete (block or poured) foundation on the back and two sides at least 6" taller than the high point of the slope. Then frame your wood walls on top of the concrete walls. Be sure to apply a waterproofer to the outside of the concrete and install a french drain before backfilling.

Another alternative, cut the hill back another two feet or so and install a retaining wall behind the shed. This will keep the soil away from the wood structure, and prevent rotting. You can find retaining wall blocks at any home center to do this quickly and easily, but there are many other options for retaining walls also.

By the time you pay for 6x6 PT timbers and all that crushed stone, you could have just layed a plastic sheet for a moisture barrier and poured a concrete slab. MUCH more durable, fewer moisture problems, easier to clean, and it will keep out bugs and other critters.

Building a wood structure in contact with the soil is just asking for trouble. Build a proper concrete foundation, cut the hill back so it's away from the building, or raise the building up above the soil.

Good luck,

Anthony

[Dioclese]

Reminds me of the word "assume", and its inference. Now, you've done it twice.

[dpb]

Dioclese wrote: ...

Indeed, I told the OP what he _should_ do to do the job. He can determine how deep that needs to be irrespective of your carping...

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[Cwatters]

There are two methods...

1) No back fill - Since it's only 2 foot you can dig out an area larger than you need and either slope the sides or build a retaining wall. Build the shed in timber with no special treatment.

2) Backfill - Then you must build in block and tank the uphill side below ground or you will have a shed full of water. Doing this in timber would be a mistake.

[Kevin]

Thanks to all for the responses. The general consensus seems to be that PT is not a great idea but may be feasable. I think I'll aire on the side of caution and build a small retaining wall just outside the footprint, and build a full shed wall. We are in "snow country" so frost and heaving is a potential issue, however, for a small shed such as this, digging and pouring a frost wall is not going to happen and seldom does in these parts.

So beyond that, the floor to the shed will be dirt (crushed stone actually) and this is a functional decision not me being cheap so no snide comments please. What would be the best way to construct a sill for the shed. I was thinking of laying 6x6 timbers in crushed rock with appropriate drainage and then attaching the sills & walls to this. Perhaps a better method would involve cement pads at the corners? or something else?

[Kay Lancaster]

Have you ever looked at the plans various extension services have put out over the years? May keep you from re-inventing the wheel. e.g.: