A good annexe doubles the living space of your Mars caravan. A poorly set up one becomes a sail in the first gust and writes off in five minutes. Here's how to set it up properly, look after it, and save it when the wind comes up.

Setup — Done Right the First Time

If you've already got the existing Setting Up Your Mars Caravan Annexe article, this complements it by focusing on the things that protect the annexe over the life of the trip — particularly in wind.

Site Selection Matters as Much as Setup

• Look up at the trees around you. Bent trees, leaning posts, debris on the ground = a windy site. Pick another spot if you can.
• Park so the van shelters the annexe from the prevailing wind, not vice-versa.
• Avoid pitching the annexe on the windward side of the van.
• Watch for natural wind funnels — gaps between buildings, valleys, gaps between trees.

The Setup Order

1. Level and steady the van first. An unsteady van means a misaligned annexe.
2. Lay out the annexe walls and roof on the ground before lifting.
3. Set up the centre arms / spreader bar first to give you the basic shape.
4. Lift the roof and secure it to the awning track.
5. Attach walls to the roof and to each other.
6. Tension the structure progressively — don't over-tension before everything is in position.
7. Peg out the walls.
8. Add storm straps over the top (if fitted) to anchor to the ground.
9. Final check — every peg seated firmly, every guy rope tensioned, no flapping fabric.

Pegging — Where Setups Fail in Wind

The Right Pegs for the Ground

• Hard ground / dirt: standard sand pegs or 200mm steel pegs work well.
• Sand: long sand pegs (300mm+) or screw-in sand anchors. Standard pegs pull straight out in a gust.
• Soft / boggy ground: 300mm+ steel pegs driven at an angle.
• Compacted gravel/clay: heavy hammer required; consider using a power drill with a peg adapter to pre-drill if it's very hard.

Pegging Technique

• Drive the peg at an angle of 30–45° away from the load (e.g. away from the annexe).
• Peg should be 80–100% in the ground.
• Avoid bedrock or buried hard layers — pull the peg, move 30cm, try again.
• If a peg goes in too easy, the ground won't hold it. Use a longer one, or use two pegs in a triangulated configuration.

Storm Straps

• If your annexe has storm straps over the top, use them. Don't skip them just because the forecast looks calm.
• Run storm straps to the heaviest, deepest pegs (or to the van's chassis points if designed for it).
• Re-tension after the first hour — fabric stretches when new, especially in heat.

The Wind-Sensitivity Hierarchy

How much wind is too much, roughly:

• Up to 20 km/h: normal use, no special concern.
• 20–40 km/h: tension up, check pegs, secure loose items, take walls down if you have any partially up.
• 40–60 km/h: consider rolling the awning in. Walls take serious load.
• 60 km/h+: awning down, walls down. Don't try to ride it out.
• Forecast 70 km/h+ gusts: pack the annexe before the wind arrives. Setting it up in 70 km/h gusts is impossible; taking it down in them is dangerous.
  

See Wind & Awning Safety: When to Pack It In in the existing help centre for more on the awning side.

Re-Pegging When Wind Comes Up Unexpectedly

Wind has come up faster than forecast. The annexe is starting to billow and lift. What now?

Quick Triage

1. Walk the perimeter — check every peg and guy rope. Re-tension anything loose; re-drive any peg that's lifted.
2. If walls are flapping noticeably, take them down. They're the biggest sail surface.
3. If the roof is lifting at corners, get more anchor points in — additional pegs, additional storm straps.
4. Get heavy items (camp chairs, table, BBQ) inside the annexe weighing down the floor edges.
5. Have a decision point — if it gets worse, you take it down. Don't try to "outwait" worsening conditions.

Taking the Annexe Down in Wind

• Drop the walls first — they're the biggest sail.
• Roll the awning if it's on awning track.
• Disassemble centre poles last (they're the spine holding it together — premature removal collapses everything).
• Stash fabric inside the van or under the awning if you can't fully pack it.
• Two people: one holds, one un-pegs. Solo: work corner to corner methodically.

Care & Maintenance Over the Trip

Daily

• Check pegs after wind events.
• Sweep dirt out of the floor — accumulated dirt eats fabric over time.
• Look for water pooling on the roof after rain — push it off; pooling stretches fabric.
• Watch for guy rope wear at attachment points.

Weekly

• Hose down panels if dusty.
• Check zippers — sand and grit kill them; brush out and lubricate with silicone spray.
• Inspect stitching at high-load points.

End of Trip / Storage

• Pack down completely dry. Wet fabric stored long-term grows mould.
• If you have to pack wet, set it up at home within 48 hours to dry.
• Brush out dirt, sand and leaves before folding.
• Roll/fold loosely rather than tightly — reduces crease wear.
• Store in a dry place out of UV.

Rain Care

• Roof should slope so water runs off, not pools.
• Push water off any visible pooling immediately — even small pools become heavy.
• Don't touch the inside of canvas in heavy rain — your fingers create wicking points that let water through.
• Check walls for leaks at seams and zips after the first big rain.

Re-Pegging When Things Have Already Gone Wrong

The annexe pulled up two pegs in a gust and is leaning. The fabric isn't torn yet but it will be soon.

1. Get everyone away from the moving structure (most injuries happen when people are inside reaching for things while the annexe is moving).
2. Find the highest-load corner first — usually a guy rope on the windward side.
3. Get a long peg into solid ground close to the original peg position, at the right angle.
4. Move to the next pulled peg.
5. Once all pegs are back in, re-tension the structure.
6. Inspect for fabric damage — small tears now become large tears in the next gust.
7. Make a call: stay set up (now that it's anchored properly) or take it down (if wind is still building).

When the Annexe Is Beyond Saving

Tears more than 10cm, broken poles, mangled track attachment — pack it down, save the bits, and book a repair when you can. Most annexe damage is repairable if caught early; ignored damage spreads fast.

The Single Best Piece of Advice

Watch the weather. Wind apps (Windy, Weatherzone) show forecast wind speed and gust speed for your exact location. Check them before setting up, and check again every morning. Predicting wind beats reacting to it.

Related: Wind & Awning Safety: When to Pack It In· Canvas & Annexe Pack-Down· Setting Up Your Mars Caravan Annexe