Retrofit my pole barn or build new?
I have a 24×48 drive shed on my property, and what I’d like to have is an energy efficient workshop (woodworking, one bay for car work, also an area for garden equipment, possibly a semi-conditioned addendum for some animals). I’m trying to decide whether it makes more sense to retrofit the shed, or just start from scratch. I’ve heard from a couple of sources that retrofitting a shed of this type is difficult.
The shed has a dirt floor, metal roof and siding, no insulation or air sealing (the ridge vent actually allows a lot of snow to come in, and even rain if it’s windy). There is electrical service there, in fact that’s where the service enters the property and goes to the house from there.
The pros are pretty obvious. The external structure is there already, there’s electricity. Maybe I could work on it in stages.
The cons:
1) location – 110 yards from the house, with no driveway connecting the two (and no driveway to the road either), orientation is not great for installing PV (something I foresee doing in the future)
2) difficulty in retrofitting insulation and air sealing, getting a concrete floor into an enclosed space, etc.
3) limitations in options for above
4) no ability to customize the space for my needs and wants
A lot of this is subjective, and I provide it mainly for the sake of interest. What I’m really wondering is, how much would it really save me to do a retrofit on such a shed? My wife’s perspective is that it’s already there, we should use it. I’d really rather not. If I can show here that it wouldn’t even be significantly cheaper, that will win the argument for me.
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Replies
Trevor,
The way I have seen those types of structures retrofitted here is by putting a layer of house wrap on the inside against the steel panels and spray foaming over that with as much foam as you care to spend money on.
The more diy friendly option is to frame it up on the inside and insulate/air seal as a new build. At that point the cost you are saving by not building new is a bit of structure, siding and roofing.
Sort of what Akos said. You're saving the equivalent cost of that building. For a simple pole barn, that's not much.
You didn't give your location. Here in zone 5, any slab that's not protected from freezing will heave if there's moisture around. Right now my main barn walk door is in danger of being unusable due to the slab heaving about an inch. Typical pole barn construction offers no protection from this. There are details I've seen to deal with this on pole barn edge, but I haven't seen them used successfully.
I am on the cold edge of zone 5. Protecting the slab is another complication. I probably would do a floating slab. Since that would place the slab edge several inches inside the pole structure, at that point I might as well just construct a building inside the pole barn. That would save me a roof and siding, but lose me a lot of square footage, and any possibility of having windows.
Trevor,
Maybe not the numbers and specs type of argument common on this forum.
One way looking at the problem is how likely are you to use a converted pole barn that is too far away, with minimal natural light that is not comfortable (or takes forever to get up to temp)? There is no point spending energy and resources to convert the pole barn if it won't actually be used. For example, my wife's studio is heated all the time, turning the heat down could work, but then waiting for it to heat up creates too much "friction" to the decision to go there, defeating the purpose of the studio.
If you have the time, resources and most important enough in the relationship "bank" to take on the scratch build to make something that is more enjoyable and usable then I would say it is worth it.
To me you are asking should I make a silk purse from my sow’s ear.
In my opinion pole barns are designed and built with a single goal to provide a dry space at the lowest possible cost. Almost all the choices made for this goal are the polar opposite of those one would make for a high performance building.
If the real question is should I build a new building or get by with this one? The answer would depend on how many years you plan on staying on this property? How many hours a week are you likely to use this space?
Walta