This isn’t exactly a question about home building but I am thinking of building a shed as if it were a house. Reason being is that it might spend some of it’s life as a shed and then convert to an office space. For that I am planning to build it as if it were a dwelling. I’m thinking that I would frame and sheath it as if it were a monopoly piece. ZIP on all sides including the floor deck which will be help off the ground by concrete blocks and by 6×6 skids. Blocks would keep it elevated and the skids would create a break between the blocks and the underside of the floor and allow it to be dragged to a new location. Tape all seams and insulate the cavities with some type of batt insulation on all sides (including the floor). Does this sound feasible? My only concern is the ZIP on the underside of the floor facing the dirt. There is no direct sunlight there so it shouldn’t degrade from UV but I am wondering about the long term exposure. Perhaps there is a better way to waterproof the underbelly. Thoughts.
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Consider Marine grade ply for the underside and potentially upgrade to a more heavily treated 6x6 material. Not all “treated wood” is the same.
Placed over well drained stone on block should help.
Hmm. Hadn't considered marine grade plywood. Doing a quick search it's not something carried at the local Home Depot or Lowe's and it's quite a bit more expensive. Almost 3x more expensive. I supposed if I am going to keep the building for a long time that might be worth looking at.
Your call.
Once built, near impossible to replace.
But then again, I’ve got some “treated ply that’s been out 35 yrs (the old dangerous formula), and a pc or 2 that have delaminated.
Seal all cuts and edges and you most likely will have no major problems.
What do you think about OSB or plywood with WRB applied?
It makes sense to build a shed like a small house, which would then be converted into an office in the near future. It seems okay to use ZIP sheathing on all sides, with a floor deck elevated off the ground on concrete blocks and 6x6 skids. Insulating all cavities is a good idea, but I'd want a more rugged waterproofing solution on the underside of that floor, when facing the ground exposure, for damage over the long haul.
"Build it like a house..." also includes air changes and make up air. See those topics if you're not already aware. You can suffocate in a tiny well-sealed space.
For sure. I wasn't ever considering living in it but air changes make sense and I should plan on that if I were ever in need to convert it into something I would spend any significant time in with windows and doors closed. I'm guessing that while I may get this build pretty close to a "house", it's likely to be leaky since I won't be spending the money on airtight doors. I'm fine with some leakage since it is ultimately a shed and not intended for comfort living.
Exactly. I built a garage with exterior insulation and a tight envelope but did not finish the interior (get to it another day/phase). There is degradation of the sheathing on roof and walls because no ventilation is installed yet. Air sealing and insulation is a system. Don't complete the system and there are consequences.