Detachable shed
We’re planning to build a garden shed in our backyard. The shed will be made primarily from timber. One spot we had in mind for the shed is in an easement on our property for a barrel sewer that runs along the back of the properties on our street. The sewer is about a metre deep. This is deep enough that if we built the shed on stumps or a slab we would be unlikely to disturb the sewer. But the management authority for the sewer reserves the right to dig up the easement if necessary to work on the pipe. So if we had a shed on the easement this might have to be demolished. Not very green.
I’ve been told that work of this nature is unlikely but there is always a possibility.
So what I thought might work is a shed that can be easily moved if necessary.
The shed dimensions are likely to be in the order of 2m width x 3m long by 2m high. We could run three trenches at the shed site down to, say, 30cm and fill these with aggregate. We could build the shed on three skids of high durability timber (with termite caps on top of the skids) with the skids sitting on the aggregate. This would potentially allow the shed to be moved relatively easily (by dragging) if necessary. The bearers across the skids would have to be strong enough to span 1m. I guess some load calculations are necessary. I was looking at some nice boards of farm grown sugar gum (Eucalyptus cladocalyx) yesterday that should do the job.
To make this even easier I thought that we could have the walls and roof essentially as discrete elements with the walls bolted to the floor assembly and the roof bolted to the walls. That way the shed could be unbolted and dismantled into easy to move sections.
Does that sound like it would work? Anyone had a crack at something similar and have some lessons learnt?
Thanks
David
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Replies
David, Houses here on Vancouver Island usually have sheds of about that dimension that often move with the owner when a property is sold. I moved mine twice. They are generally framed with the beams flush and sit on 8" concrete pier blocks. When it comes time to move you can either slide skids underneath and haul them with a winch or pickup truck, or get a flatbed truck with a hoist if they are moving further.
David,
Here in Vermont, farmers often build sheds on skids so they can be moved with a tractor. As you proposed, you need to start with two beefy beams of rot-resistant wood. The skids should have tapered ends (like ski tips).
What Martin & Malcom said, plus you can dispense with the trenches and crushed stone. The structural loads are tiny and the pier blocks or skids can sit directly on any reasonably compacted soil (i.e. not recently tilled). A wood-framed shed will be robust enough to stand up to a minor amount of differential settlement and you can always shim it up with a brick or two if the floor starts to get out of level. Just be sure to use a lightweight roofing material such as corrugated metal sheet which will not be harmed by movement - no slates or clay/concrete tiles! Make the structure in demountable panels if you like especially if machine access is likely to be difficult in the future. I made a shed that way for similar reasons about thirty years ago, of course when I checked on Google Earth it still seems to be exactly where I left it....
Thanks for the responses.
James: I thought placing the skids on aggregate would help reduce biological wear and tear on wooden skids from termites, other borers and rot. A high durability timber should get 35+ years of lifetime in ground contact but I thought the aggregate would help as it would drain well. Maybe the aggregate trenches would fill up with dust and detritus over time and not drain as well.
I haven't built anything from timber frames bolted together. I was wondering if this raised any potential gotchas in manufacture or once built.
Thanks
David