Kip Ping, PE, SE — Principal and Founder, Pinnacle Engineering
If you missed Part 1, I’d encourage you to start there. It covers the bigger picture of what barndominiums are, why they’ve become so popular, and the general questions every prospective owner should ask before committing to one.
This post gets into the structural side specifically, which is where I spend most of my time as a Structural Engineer and Founder at Pinnacle Engineering.
I want to be clear upfront: I’m not here to talk anyone out of building a barndominium. But I do think people deserve to know what they’re getting into structurally before they sign a contract or order a kit. These are the top things I look for when I’m evaluating one of these projects.
Barndomenium construction has agricultural roots, and that matters
Barndomenium, or post-framed buildings, as I’ll be referring to them, were developed for agricultural use.
That background shows up in how they’re designed and built. A farm shed that loses some siding in a windstorm is an annoyance. The same scenario in a home is a much more serious problem, and the engineering standards reflect that. When you’re adapting a building system designed for a shed into a primary residence, the design needs to be brought up to match that end use. Not every supplier does that automatically.
One specific issue worth noting: post-frame buildings are designed to allow greater movement in the wind than traditional wood-framed structures. For a shed, that flexibility is a non-issue. For a home with brick veneer, tile, or other brittle finishes, that movement can lead to cracking. If your barndominium plans include those kinds of finishes, the structure needs to be designed to account for it.
Wood in Contact with the Ground is a Durability Risk
Many post-framed buildings have wood members that are exposed to the ground or in direct contact with concrete or masonry. In an agricultural building, this is often acceptable. In a home where you expect the structure to last for years, it deserves more scrutiny. The long-term durability of those connections should be part of the conversation before you build.
The Foundation is Often the Biggest Structural Weak Point
This is where I see some concerning gaps. Post-framed buildings typically use a simple foundation system that works fine under the light loads of an agricultural structure. When you add the weight of drywall, flooring, cabinetry, and all the finishes that make a barndominium livable, that foundation may no longer be adequate.
Upgrading the foundation after the fact is expensive, often disproportionately so relative to what the original “pole-barn” approach would have cost. It’s worth getting that foundation designed correctly from the start.
For metal building barndominiums specifically, I’d encourage anyone reviewing plans to look carefully at the foundation drawings. Red flags include a plan that shows a 4-inch slab everywhere, without thickened edges or footings; no reinforcing is called out in the concrete; and no notes on how to prepare the grade before installing the concrete. It’s also not uncommon to see a supplier include a “foundation plan” but then include a note somewhere in the documents stating they are not responsible for the foundation design and that it’s the homeowner’s responsibility. That is a significant liability to accept.
Energy Efficiency and Moisture are Related Structural Concerns
Because post-frame and metal building systems are constructed differently, getting the insulation right matters more than it might in a conventional home. When the system isn’t built correctly, condensation can accumulate inside the wall or roof assembly, which leads to long-term durability problems. This isn’t a reason to avoid barndominiums, but it is a reason to make sure whoever is designing and building yours understands how to detail it properly.
Be Mindful That DIY Kits Can Fall Short
To say it plainly: DIY building kits are almost never adequate for use as a home. They are typically designed to meet the bare minimum requirements for agricultural use and often fall short of residential building code requirements in multiple areas. If you’re considering a kit, it should be reviewed and modified by a licensed engineer before you build from it.
Require an Engineer’s or Architect’s Seal on Your Drawings
Because barndominium structures are not covered by prescriptive building code provisions, the drawings should carry a seal from a licensed engineer or architect. If a supplier tells you they can’t provide that, it is a red flag. It means there is no licensed professional taking responsibility for whether the structure is safe and code-compliant.
The Bottom Line
A structurally sound barndominium should be designed for use as a home, not adapted from a farm shed. That means a foundation sized for residential loads, framing designed to the right code standards, and a licensed professional whose seal is on the drawings. If a supplier isn’t offering that as a baseline, it’s worth asking why.
If you are working through a barndominium project and want a structural engineering perspective early in the process, we are glad to help. Reach out to our team here.
