Barndominium Pros and Cons: An Honest Structural Comparison
Most pages on this subject are written by someone selling one answer. This one is a comparison, and it has a real list on both sides. The useful starting point is that "barndominium" is not a construction method — it is a look. Underneath it there are three genuinely different buildings: a post-frame building on embedded or pier-mounted columns, a steel-frame building on a red-iron or pre-engineered skeleton, and a conventionally framed house wearing metal cladding. They share almost nothing structurally, they fail in different ways, and the advantages people repeat about the category usually belong to only one of them. So this page separates the structure from the styling, sets the honest advantages against the honest disadvantages, and then does the part nobody else does: applies both to Missouri ground, where the frost line varies by more than twofold between named jurisdictions, where a large part of the north sits on a soil with a perched winter water table, and where the Ozarks carry roughly 16,000 mapped sinkholes. If you want the question of whether it is the right decision for you specifically — resale, appraisal, financing, the shop-plus-house case — that is the companion page, and it answers something different from this one.
Figures on this page are cited third-party or government data, not a quote from Missouri Barndominium Builders.
Three different buildings, one word
Before any advantage or disadvantage means anything, work out which of these you are actually being sold. The differences are structural, not cosmetic, and most of the arguments people make about barndominiums are really arguments about one of the three.
Post-frame
Columns at wide centres — commonly eight to twelve feet — either embedded in the ground on a footing or set on piers or brackets above grade, with horizontal girts and roof purlins spanning between them and the sheathing or steel panel acting as a diaphragm. There are no studs doing structural work and no interior bearing walls. The foundation is the post holes plus a slab that is usually not carrying the building. It goes up fast, it is efficient in material, and its two characteristic vulnerabilities are at the ground line, where an embedded column meets soil and water, and at the diaphragm, which is what resists wind and seismic load and which must not be casually cut into afterwards.
Steel frame
A red-iron or pre-engineered skeleton of rigid frames on anchor bolts, with secondary purlins and girts and a steel skin. Clear spans are large and completely free of internal support, and the frame is engineered as a unit — which is a strength and a rigidity. The trade-off is thermal: steel is an efficient conductor, so every point where the skin fastens to the frame is a bridge, and getting a genuinely warm, dry envelope onto a steel frame requires continuous insulation and a thought-through vapour strategy rather than batts between members. Modifying a pre-engineered frame later is an engineering exercise, because the frames were designed as a set.
Conventionally framed, metal clad
A stud-and-truss house that looks like a barn. Structurally it is a house: bearing walls, standard spans, conventional foundation options including a full basement, and the whole familiar toolkit of trades and details. It gets the appearance without the clear span and without most of the disadvantages further down this page, and it also gets none of the shell-speed advantage. This is a legitimate and under-discussed option in Missouri, where basements are ordinary, and it is worth pricing alongside the other two rather than assuming the label commits you to a method.
Why the distinction decides the argument
"Barndominiums are cheaper" is a claim about a shell, not about a house — the interior finish, the mechanical systems, the kitchen and the bathrooms cost what they cost in any building. "Barndominiums are hard to insulate" is a claim about a steel frame with a steel skin, not about a post-frame building with a conventional insulated wall assembly hung inside it. "You can move any wall" is true of the clear-span versions and untrue of the third. When someone quotes you an advantage, ask which of these three buildings they are describing.
Where the structure genuinely wins
These are the advantages that survive scrutiny — the ones that follow from how the building is put together rather than from marketing.
No interior bearing walls, which is a permanent advantage
In a clear-span building the roof load goes to the perimeter frames and the interior partitions carry nothing but themselves. That gives you a plan with almost no fixed geometry: rooms can be any size, an open volume can run the length of the building, and — the part that matters more over twenty years — you can reconfigure later without a structural engineer being involved in the partition work. In a conventionally framed house the same change means beams, posts and a load path. This is the single most durable advantage of the type and it is why the shop-plus-house program works so well in this shell.
One foundation, one roof, one envelope for two very different uses
The shop-and-dwelling combination is not just a floor plan; it is a saving in structure. A detached shop needs its own foundation, its own roof, its own drainage and often its own service entrance and heating. Under one clear-span roof it needs none of those separately. That is real, and it is the reason this building type exists as a category rather than as a style. Do check the local rules on it before assuming — several Missouri jurisdictions regulate the ratio directly, and Osage Beach sets a minimum proportion of defined living space by lot size, at 60, 50 and 40 percent on progressively larger lots and unregulated above 40,000 square feet.
A simple roof, which is a maintenance advantage more than a cost one
Most of these buildings have one ridge, two planes and very few penetrations. Compare that with the multi-hip, multi-valley roofs common on conventional houses of the same footprint. Valleys are where roofs leak, flashing is where they leak next, and both are proportional to complexity rather than to area. A simple metal roof with long unbroken runs is a genuinely lower-maintenance object over decades. It is also the reason a barndominium can be re-roofed as a discrete job rather than as a project.
Shell speed, and a build sequence you can pause
A post-frame or steel shell can be closed in quickly relative to a stick-framed house of the same footprint, which gets you a weathertight, lockable envelope early. That has a practical consequence people underrate: the interior can be finished in stages, or partly finished, or finished later, without the building deteriorating in the meantime. For an owner doing part of the work themselves, or building in phases, that flexibility is worth more than the headline speed.
Large openings are cheap here and expensive elsewhere
A fourteen-foot overhead door in a bearing wall is a structural event. In a clear-span frame it is a panel decision. If your program includes equipment access, a workshop bay, an RV door or anything else that wants a wide opening, this shell gives it to you at a fraction of the structural cost — and it gives you the option of adding one later on a wall that was never carrying load.
The frame is not what wears out
Steel frames and treated post-frame columns are long-lived under the two conditions that matter: keep water away from the ground-line connection, and keep condensation off the inside of the skin. Both are detailing questions rather than material ones, which is a fair summary of this building type generally. What you should be asking a builder about is the ground-line detail and the vapour strategy, and a builder who answers those two questions well is telling you more than any warranty document.
Where the structure genuinely loses
A pros-and-cons page whose cons are soft is worthless. These are the real ones, in roughly the order they cause trouble.
Moisture behind a metal skin is the characteristic failure
A steel panel is impermeable and it is cold. Warm interior air that reaches the back of it condenses, and unlike a wood-sheathed wall there is nothing hygroscopic to buffer the moisture while it dries. The result is water running down the inside of a wall or dripping off a roof panel in the first cold snap, wet insulation, and corrosion at fasteners. This is entirely preventable with a continuous air barrier, the right side of the assembly for the vapour retarder, a vented or fully sealed roof assembly rather than a half-measure, and insulation that keeps the panel above dew point. But it must be designed, and it is the single most common serious defect in this building type. In a jurisdiction that has deleted its energy chapter, nobody will check it for you.
Thermal bridging, and why the R-value on the invoice is not what you get
In a steel-frame building every purlin, girt and fastener is a conductive path through the insulation. The assembly's actual performance can fall well short of the nominal value of the insulation installed in it, and the shortfall is concentrated at exactly the places where condensation then forms. The fix is continuous insulation outboard of the framing, or thermal breaks at the fastening line, and it is a real cost that belongs in the comparison honestly rather than being discovered later. Post-frame buildings with a conventional insulated wall assembly built inside the columns have much less of this problem, which is a good example of why the three-buildings distinction matters.
Sound, in both directions
Rain and hail on a metal roof are loud, and the standard reassurance — that decking and insulation solve it — is only partly true; the fully insulated, decked assemblies do a good deal, the minimally insulated ones do not. Inside, a clear-span building tends toward hard surfaces and large volumes, which means long reverberation and poor speech privacy between spaces. And a shop bay attached to living space transmits impact and machine noise through a shared slab and a shared structure far more effectively than a detached building would. If the shop will be used at hours the household is asleep, that is a design problem to solve at the drawing stage.
Changing the shell later is engineering, not carpentry
The flip side of the interior freedom is that the exterior is doing all the structural work. In a post-frame building the wall and roof sheathing is the diaphragm resisting wind and seismic load; in a pre-engineered steel building the frames were designed as a set for a specific configuration. Cutting a new opening, removing a bay of bracing or adding a large dormer is not a discretionary change — it needs the original design assumptions and usually a Missouri-licensed professional engineer. Owners who assume the whole building is as flexible as its interior are in for an expensive surprise.
Slab-on-grade means your services are in concrete
Most of these buildings sit on a slab, which means drainage, and often water supply and some electrical, are cast into it. There is no crawlspace to crawl into and no basement ceiling to open up. A drain line that needs rerouting means cutting and patching concrete, and a bathroom relocated five years later is a much bigger job than the same move in a house with an accessible underside. Plan the plumbing carefully at the outset, and give the drawings the same scrutiny you would give the elevations. In Missouri, where a basement is ordinary construction, this is worth weighing against the alternative rather than accepting as inherent.
Volume costs money to condition, every year
Tall ceilings and open plans are much of the appeal, and they are also more air to heat and cool and a stronger stratification problem in winter. Ceiling fans and careful supply-air design mitigate it; they do not remove it. The honest way to think about this is that the same square footage in a barndominium is usually a larger conditioned volume than in a conventional house, and that shows up in equipment sizing at the start and in bills forever afterwards.
Appearance rules can simply prohibit it
Covered in more detail above, but it belongs on this list because it is the disadvantage most likely to end a project rather than complicate it. A minimum roof pitch, a minimum eave projection, a minimum dwelling floor area or an outright prohibition on corrugated metal siding is not a hurdle you clear with a better submittal — it is a bar on the exterior the building is made of. Read the zoning district text for the specific parcel, in the specific district, for a site-built single-family dwelling, before anything else.
The financing and appraisal path is not the default one
This is the disadvantage most people discover latest. A less common building type in a rural market gives an appraiser fewer directly comparable sales to work from, and lenders vary in how they treat a large shop area within the same envelope. None of that makes it impossible, and none of it is a Missouri peculiarity — but it is a real source of delay and of surprise. It has its own page, because the answer depends heavily on who you are and what you are trying to finance.
Claims that do not survive checking
Four things repeated constantly about this building type, weighed against what can actually be sourced.
"It is much cheaper per square foot"
There is no reliable published cost figure for a Missouri barndominium, and this site will not manufacture one. The reasons are structural rather than evasive: Missouri assesses the dwelling and its site as residential property under RSMo 137.016(1.1) whatever the building is made of, there is no state-level construction reporting that separates this building type from any other house, and the vendor figures that circulate are shell prices being compared against finished-house prices. What can be said honestly is narrower and more useful: the shell is a smaller fraction of a finished house than people expect, the interior costs what interiors cost, and the genuine savings are in the shop-plus-house consolidation and in the simple roof rather than in the square-foot rate.
"A barn does not need a permit"
Two things are wrong with this. The first is that the agricultural exemptions in Missouri zoning law cover buildings used for the raising of crops, livestock, orchards or forestry, and a dwelling is not one of those. The second is that the exemption is from zoning and not from anything else — the building-code sections of RSMo Chapter 64 contain no farm exemption at all, and the septic permit, the floodplain permit and the driveway permit are separate instruments that do not care what you call the building. The legal guide on this site works through all of it with the statutes cited.
"Metal buildings and lightning"
A steel building is not more likely to be struck than any other building of the same height and exposure, and a continuous conductive shell is in principle a favourable thing rather than an unfavourable one because it gives current a path to ground away from the interior. What matters is bonding and grounding done properly, which is an electrical detail — and in a Missouri county with no building code, the utility inspects the meter base and nothing behind it, so this is one of the specific things worth paying an independent inspector to look at.
"You can put it anywhere because rural Missouri has no rules"
This site has now found three fire protection districts acting as the building department in counties with no county code, one of them running plan review, staged inspections and occupancy sign-off across 227 square miles. Separately, the septic construction permit is statewide with no county gap, the floodplain permit applies wherever a participating community has mapped hazard area, and the driveway permit applies on any state route. The correct sentence is that in much of rural Missouri no one will inspect your building — not that nothing is required, and not that no one might.
Reading this because you are weighing a build? The next step is a plan drawn for your program.
What's different about Missouri
Frost depth sets your foundation, and it is not one number
For a post-frame building this is the most consequential figure on the page, because it fixes the depth of every post hole and pier. Across named Missouri jurisdictions the published frost line depth runs from 36 inches in the Kansas City Residential Code 2018, through 30 inches in Boone County's addendum to the 2012 International Codes, in St. Charles County's 2021 Residential Code and in Jefferson County, to 24 inches in the City of Springfield's 2018 IRC adoptive ordinance and in both Osage Beach and Lake Ozark, 18 inches in Nixa and the city of Ozark, and 15 inches in Sikeston. That is more than a twofold spread, and Springfield and Nixa publish 24 and 18 twelve miles apart. Never accept an inherited neighbouring figure — get the jurisdiction's own filled-in Table R301.2(1) in writing.
Missouri is the first state in this series where a basement is ordinary
The frost line alone gets you a good part of the way to a foundation wall in most of the state, and full basements are conventional residential construction here in a way they are not further south. That changes the comparison. A post-frame building sitting on embedded columns and a slab does not naturally produce a basement, and adding one means a different foundation system underneath the same shell — which is a design decision made at the beginning, not a change order. If a basement matters to you, say so before anyone prices a frame, because it moves the whole foundation strategy rather than adding a line item.
Claypan soils and a winter water table across northern Missouri
Thirty-eight Missouri counties carry a recognised Central Claypan series as a major map-unit component, derived from the USDA-NRCS Soil Data Access database, with the fullest suite in the northeast core. The official series description for the Mexico series — the type location is in Montgomery County — classifies it as a fine, smectitic, mesic Vertic Epiaqualf, which is the shrink-swell mineralogy and the shrink-swell behaviour stated in the taxonomy itself, puts the top of the claypan 7 to 18 inches down, describes the soil as poorly drained with very slow permeability, and records a perched water table with an upper limit of half a foot to a foot and a half below the surface from December to May in most years. For a slab and for embedded columns that is a drainage strategy you design around. For the septic system it is usually the binding constraint on the whole build.
Karst in the Ozarks — and it is not uniform either
Missouri Department of Natural Resources has mapped approximately 16,000 sinkholes and about 7,500 caves and warns that voids may be plugged or capped with soil or thin rock and "discovered during excavation, by drilling, or through geophysical exploration." But "the Ozarks are shallow to bedrock" is a reflex rather than a fact: measured from USDA-NRCS Soil Data Access, Greene County's survey area carries bedrock within roughly twenty inches on about 4 percent of its area, while Taney County's carries it on about 38 percent — nine times as much, with 63 percent of the survey area in map units whose slope class starts at 15 percent. Measure your own survey area. What actually governs foundations around Springfield is chert content and a fragipan mapped on roughly 38 percent of Greene County at 16 to 33 inches, which is the band the city's 24-inch frost line lands inside.
What your jurisdiction deleted from its energy chapter matters as much as what it adopted
For a metal-skinned building the envelope specification is most of the job, so the amendment list is the document to read. Clay County's § 150.16 adopts the 2012 International Codes and then deletes the air-leakage test, the slab-on-grade, basement wall, duct, lighting and thermostat provisions, amends wood-framed walls to R-13 and adopts no International Energy Conservation Code at all. Osage Beach deletes the energy efficiency chapter of the residential code in its entirety. That is not a licence to build a poor envelope — it means the jurisdiction will not check yours, and the consequences of getting it wrong land on your heating bill and on the back of your steel rather than on a plan reviewer's desk.
Some Missouri jurisdictions prohibit the exterior itself
This is a real constraint and it is district-specific, so scope it before you conclude anything. Lake Ozark § 405.100.E prohibits "the use of flat or corrugated sheet metal for the exterior walls or roof covering," with standing seam excepted, alongside a 4:12 minimum roof pitch, a 12-inch eave and a 22-by-40-foot minimum dwelling. Osage Beach carries the same ban under §§ 405.140 and 405.150 by Ordinance 20.72 with a 3:12 minimum pitch — but not in its A-1 Agricultural district, and not in one inch of the unincorporated county. Clay County's Land Development Code § 151-10.6 excludes smooth, ribbed or corrugated metal or plastic panels as house siding and corrugated, galvanized and zinc roofs. In Christian County, by contrast, the metal and pitch prohibitions attach only to manufactured homes in manufactured-home subdivisions and the city of Ozark's prohibited-materials rule is a commercial design guideline, so a site-built dwelling in the rural districts faces no material restriction at all.
Pros and cons, honestly
Pros
- Clear spans and no interior bearing walls: the floor plan is not fixed by structure, and it can be reconfigured later without a load path being involved.
- A shop and a dwelling share one foundation, one roof, one envelope and often one service entrance, which is a genuine structural saving rather than a styling choice.
- Simple roof geometry — usually one ridge and few penetrations — which is where long-term roof maintenance and leak risk actually come from.
- The shell closes in quickly and can be locked up before the interior is finished, so the build can be phased or partly owner-completed without the building weathering.
- Wide openings for equipment, vehicles or a workshop bay are inexpensive in a clear-span frame and can be added later on a wall that was never carrying load.
- Steel frames and treated post-frame columns are long-lived, and the two things that shorten their life — water at the ground line and condensation on the skin — are detailing decisions you can inspect and verify.
- In much of Missouri the design is not constrained by a plans examiner's preferences, because in 89 of the state's 114 counties the county has no authority to hold a building code at all.
Cons
- Condensation behind an impermeable, conductive metal skin is the characteristic failure of this building type. It is preventable by design, and in a jurisdiction that has deleted its energy chapter nobody will check that it was designed.
- Thermal bridging through steel purlins, girts and fasteners means the assembly performs below the nominal insulation value, and the shortfall concentrates exactly where condensation forms.
- Rain and hail on a metal roof are loud, hard-surfaced clear-span interiors reverberate, and a shop bay sharing a slab and a structure with living space transmits impact noise very efficiently.
- The exterior is the structure. Cutting a new opening or removing bracing later needs the original design assumptions and usually a Missouri-licensed professional engineer, which is the opposite of the interior's flexibility.
- Slab-on-grade puts drainage and often supply lines in concrete, with no crawlspace or basement ceiling to reach them through — so a plumbing change later means cutting the floor.
- The same floor area is usually a larger conditioned volume than in a conventional house, which shows up in equipment sizing at the start and in energy use permanently.
- Several Missouri jurisdictions prohibit corrugated or flat sheet metal as house siding or roofing outright, or impose minimum roof pitch, eave and dwelling-size rules the standard package does not meet.
- Fewer directly comparable sales in a rural market makes appraisal less predictable, and lenders differ in how they treat a large shop area inside the dwelling envelope.
- No county building code also means no independent check on workmanship. In a no-code Missouri county the electric cooperative inspects the meter base and explicitly not the wiring behind it.
Is a barndominium structurally as strong as a conventional house?
What is the biggest thing that goes wrong with these buildings?
Are barndominiums cheaper than a conventional house?
Can I have a basement under a barndominium in Missouri?
Will a metal roof be unbearably loud in a Missouri thunderstorm?
How do I insulate one properly?
Is post-frame or steel frame better?
Does the shop half have to be smaller than the house half?
Questions answered? Tell us what you want to build and we will put real numbers against it.
Keep reading
The pages that answer the next question this one raises.
Are barndominiums worth it?
The companion decision page: resale, appraisal, financing friction, the shop-plus-house case, and who this building type is not right for.
Read itBarndominium laws and codes in Missouri
Who is legally allowed to regulate your parcel, how to find out which of them actually does, and what each one will and will not look at.
Read itPost-frame homes
The column-and-girt version of this building, and the ground-line and diaphragm details that decide how long it lasts.
Read itSteel construction
Red-iron and pre-engineered frames: the widest clear spans, and the thermal detailing that has to come with them.
Read itShouses
The shop-plus-house program specifically, including the local rules that cap accessory floor area or set a minimum share of living space.
Read itWant a real number instead of a range?
Start your plans and we will come back with a budget for what you actually want to build, not a national average. Send the parcel ID or an address when you have one and we will price it against your land. That conversation costs nothing.