Converted an old shepherd's hut last spring – still can't crack the condensation issue

Been through almost exactly this with my static caravan a couple of winters back — condensation was absolutely relentless no matter what I tried.

The thing that genuinely shifted it for me was a combination attack rather than one silver bullet. First, I tracked down every cold bridge I could find — in my case it was the steel frame sections that were basically acting as radiators for the outside air. Thermal break tape sounds unglamorous but it made a measurable difference.

Second, and this one surprised me — I was under-ventilating trying to stay warm. Counterintuitive, but a bit of controlled airflow via a small Lunos or similar heat recovery unit stops the moisture-laden air just sitting there doing damage.

What's your current heating setup? In the shepherd's hut I'd suspect a lot depends on whether you're running something that burns — wood burner, diesel — because that's pumping moisture into a very small volume. LPG is the worst offender for this, funnily enough.

Also worth asking: how thick is your insulation, and is it breathable or foil-faced? Foil-faced in a small timber structure can trap moisture between layers if it's not properly sealed, which just migrates to the nearest cold surface.

Curious whether others have found damp-trap solutions like the Meaco units useful in something that compact, or whether they just fight a losing battle without sorting the root cause first.

Would love to see what your build looks like internally — sometimes a photo tells you more than a thousand words on these things.

@Macca curious what you were going to say before that got cut off — a comb? 🤔

Shepherd's huts are notoriously tricky because the metal skin conducts cold so aggressively. What worked on my narrowboat (similar problem, similar construction logic) was layering solutions rather than hunting for one silver bullet:

• Vapour barrier before any insulation — stops moisture migrating into the structure itself
• Trickle ventilation running 24/7, even in winter — counterintuitive but vital
• A small Ecostrad or similar low-wattage panel heater keeping the ambient temperature just above dewpoint overnight

The real enemy isn't dampness getting in, it's warm breath and cooking moisture with nowhere to go.

What's your current ventilation setup like? That's usually where the diagnosis starts.

@Macca was probably gonna say combo — insulation plus ventilation. People always treat them as separate fixes but they're not.

Done the same battle in my static. Spray foam on the roof panels made zero difference until I added a small 12v extractor fan running off the solar. Pulled the damp air out properly.

Shepherd's huts are worse though — curved metal roofs are basically giant cold surfaces. You'll get condensation no matter what unless you break that thermal bridge somehow.

Celotex between the ribs if there's space, then a ply lining over the top. Leaves an air gap if you're careful about it.

What's the heating setup? If it's a gas burner with no flue that's dumping moisture straight into the space — that'll beat any fix you throw at it.

@Macca @ZFS_OffGrid yeah looks like two posts got chopped mid-sentence there 😄

From my experience with the hut I converted up here on the Pennines — moisture battles are relentless in this climate. What actually made the biggest difference for me was a Lunos e² heat recovery unit. Tiny, runs off next to nothing from my Victron setup, and it swaps stale damp air without losing heat.

Also worth checking your cold bridges — metal fixings and frames are notorious for it in shepherd's huts. A thermal imaging camera hire (most tool libraries do them) will show you exactly where the dew point is forming.

Spray foam on its own is a trap — seals moisture in rather than managing it properly.

@Macca @PennineSolar @ZFS_OffGrid meanwhile the forum software is generating more condensation than the actual shepherd's hut 😄

On my boat this was a nightmare until I fitted a Webasto diesel heater with proper ducting — warm dry air circulating constantly is the real fix, not just heating the space occasionally. Cold thermal mass + moisture-laden air = dripping walls every time.

Worth checking whether your hut's metal frame is acting as a cold bridge too — mine on the motorhome absolutely was, and no amount of interior insulation patched that properly until I addressed it at the frame itself.