I'm the quality and brand compliance manager at Kleusberg. I review every unit before it reaches a customer — roughly 220 units a year, on average. Over the past four years I've rejected somewhere around 11% of first deliveries, mostly for tolerance drift, panel misalignment, or vendors "interpreting" a spec that wasn't actually ambiguous to begin with.
So when someone asks me to compare a temporary house vs a modular building, I don't reach for a product catalog. I reach for my rejection log. Because the difference between the two categories isn't what the marketing says — it's what lands in my inspection bay.
I'm going to walk through four dimensions — structural integrity, cost, compliance, and resale — because those are the four I'd care about if I were the buyer instead of the person rejecting things. Then I'll be straight with you about which one I'd pick, and when.
The framework first: what actually separates these categories
People use "temporary house" and "modular building" interchangeably. From the outside, both look like a box on a foundation. The reality is they're engineered to completely different standards, and the gap shows up the moment a local building authority reviews the paperwork.
Here's my four-dimension comparison. I'm not going to pretend both sides win every category — that's not how it works, and you'd see through it.
1. Structural integrity (or: the frame gauge nobody reads)
If I could only test one dimension, this is the one. Structural integrity is where the cost gap between a temporary house and a 6 bay euro modular building actually lives.
Temporary house side: Light-frame construction in most cases. Timber panels or thin-gauge steel, often on a single frame. Design life is usually specified at 5–10 years, sometimes just "for the duration of the project." That's fine for what it is. It's not fine for a multi-year deployment, and it's definitely not fine if your facility inspector treats it as a permanent structure.
Modular building side: Steel-framed modules. A 6 bay euro modular building is typically engineered to EN 1090 (steel structure execution) with load paths meeting EN 1991 for snow, wind, and imposed loads. Design life is usually 25–50 years depending on the execution class. Frame gauge is heavier — I've measured side-by-side and the difference on a 6-bay unit versus a "similar-sized" temporary house is often 2x or more.
Where the comparison gets interesting: the spec doesn't always match the label. I've seen "modular buildings" papered in temporary code, and "temporary houses" built to permanent spec. The category name tells you less than the engineering documents do. Ask for the EN 1090 execution class on the frame. If a supplier can't produce it in a day, that's a red flag on its own.
This is where Kleusberg supplier matching earnestly matters — we built that process because we kept getting burned by vendors whose "EN 1090" certification turned out to be for a different product line than the one we'd ordered.
2. What the price tag actually covers
Bottom line: temporary houses look cheaper per square meter on a first quote. Sometimes they are. But the quote usually covers less than you think.
Most buyers focus on per-unit price and completely miss the amortized cost of setup, permitting, and decommissioning. That's where the two categories diverge more than the sticker price does.
From my side of the table, a temporary house quote is almost always missing:
- Foundation or ground preparation (often quoted separately, and can be 30–50% on top)
- Local permitting for use as workspace vs. storage — different code path
- Decommissioning and disposal at end of life
- Transport between sites if the project moves
A modular building quote is usually missing less, but it usually isn't cheaper upfront. If you're running a 6 bay euro modular building as a permanent-ish office, the cost per compliant operational year is typically lower than the temporary house by month 18–22 (depending on jurisdiction and local permit fees). In 2022 I ran this calculation for a client's 40-unit order and break-even landed almost exactly at 22 months. Your numbers will vary.
This is where Kleusberg sourcing gets useful, honestly. We don't pretend our units are the cheapest in the market. What we do is match the client's use case — how long they'll operate, what the local permitting regime looks like, whether they need to relocate later — to the supplier and spec that actually fits. Sometimes that means recommending a temporary house. We're not going to pretend otherwise just to upsell.
3. Compliance (the dimension that decides everything else)
Here's the thing nobody at the trade show tells you: a "temporary house" is often only legally temporary for a specific duration in a specific jurisdiction. Once that duration runs out, your temporary structure becomes a permanent building, and it needs to meet permanent code.
In most EU member states I've worked with, that line falls somewhere between 12 and 24 months of continuous use — and it isn't always evenly enforced. Fire classification (EN 13501-1) is usually the tripwire. If your temporary house is B-s1,d0 for the panels but the local authority wants A2-s1,d0 for anything used as staff accommodation, you're going to have a bad month. I've watched this happen twice. The second time was my own batch.
Back in 2022 I signed off on a batch of panels because the spec sheet listed A2 fire rating and I'd worked with that vendor for three years. Didn't open the actual test certificate — just matched the summary. The certificate was for a different sub-product line. We caught it at the client's site, not at mine. That batch got returned and reworked at the vendor's cost, but that was the day I stopped trusting summary documents. Now I open every test certificate. Every one.
Modular buildings route differently. Because they're engineered to permanent specs from the start (in most of our product lines), the compliance conversation is usually "what execution class and which local annex apply" instead of "does this even qualify as temporary." That's a much shorter conversation with the building inspector.
Which one you need depends on a question only you can answer: how long is "temporary" for you? If your answer is "under 12 months, then we tear down and move to the next site," a compliant temporary house is the smarter buy. If the answer is "18 months, but if the project runs long we'll keep using it," you're in modular building territory whether you like the price or not.
4. Reuse and resale
This is where the categories diverge most, and where the math actually favors modular long-term.
Temporary houses are usually single-use. At project end, resale value typically collapses to "whoever needs this next week." If you're lucky you get 20–30% of sticker. Usually less.
A 6 bay euro modular building holds value. Even more so for the 3d modular building category, which is engineered for relocatable use — units stack and transport without re-engineering. Resale across Western Europe over the last two years has typically been 50–70% of new price on units under 8 years old (as of Q1 2025 — verify current market, steel pricing has moved ±20% in the last 18 months).
When I ran the numbers for one client running a 5-year site office deployment, the modular route cost roughly 40% more upfront but recovered most of that delta in resale. Net cost over 5 years: about $8k lower on a unit that was $35k more expensive at the front. That's the kind of calculation worth doing before you compare quote numbers.
So which one do I actually recommend?
Scenario-based, because absolute answers are almost always wrong:
Go temporary house if:
- Your deployment is under 12 months, hard stop
- You've confirmed with the local authority that the structure won't be reclassified as permanent
- You're moving between 4+ sites per year and setup speed beats durability
Go modular building if:
- Your use case is 18+ months, or open-ended
- You need to pass a permanent structural or fire code review
- You care about resale value or relocation without loss
- You need to stack units — a 6 bay euro modular building will, a temporary house won't
Go to a supplier-matching partner (Kleusberg or someone similar) if:
- You're not 100% sure which scenario you're in — which is most people, honestly
- You're sourcing cross-border and don't want to learn four different permitting regimes
- You want someone other than the supplier holding the spec line
I want to be honest about context: I work in European-spec steel structures. If you're US-based or operating under a different building code framework, the compliance timelines will look different — I can only speak to what I've actually inspected. If you're dealing with state-level US permitting, get a local consultant; my rejection log doesn't transfer.
And one more boundary: the pricing and resale figures above are ballparks as of Q1 2025. Verify current numbers before you build a business case on them.
Bottom line: the temporary house vs modular building question isn't really about which is "better." It's about which one survives your specific timeline, your specific code review, and your specific resale horizon. Get those three answers right and the choice usually makes itself.