How to Make and Use a Rain Collector in Project Zomboid (Build 42.19)

Vanilla Build 42.19 · outdoor rain collectors · 400 L / 600 L · purify tainted rain · plumb fixtures with a pipe wrench

Rain collector Outdoors carpentry build

Planks 4 small · 6 large

Nails 4 small · 5 large

Garbage Bags 4 bags, either size

Tarp 1 tarp replaces bags

Hammer Kept; other hammers OK

Pipe Wrench Plumb fixtures

Purify tablets Vanilla chemical option

Build 42.19 rain collector table

Four outdoor recipes share two sizes: garbage-bag liner or tarp liner for the small crate and large barrel. They sit under Outdoors carpentry. The skill gate is Woodwork (still labeled carpentry in many UIs).

Rain factor is how fast the container fills while exposed to rain—not a percentage of capacity per second. The small crate’s higher factor (0.4) fills faster than the large barrel (0.25), even though the barrel holds more water overall.

Large barrels support an open/closed lid toggle. Closing the lid keeps the 600 L container but stops rain intake—close it when you want to stop collecting, and leave it open when you need rain.

How to craft and place

1. Raise Woodwork to 3 (small) or 5 (large). Books, early TV carpentry shows, and ordinary wood builds all help—see the carpentry guide.
2. Gather a hammer (or any accepted hammer tool), planks, nails, and either four garbage bags or one tarp. Garbage bags are often the bottleneck: kitchens, dumpsters, and trash bags on zombies are common sources.
3. Open the build / crafting UI and choose the Outdoors rain-collector recipe that matches your liner (bags vs tarp).
4. Place the finished collector fully outdoors under open sky—not under a roof, overhang, or fully enclosed room. Roof-top tiles that still count as outside work well and are ideal for plumbing layouts.
5. Wait for rain, then right-click to drink, fill bottles, or manage fluids. Treat collected water as tainted until you purify it.

Using collectors: fill, access, and move

Outdoor placement

Collectors only gather when the square is outside. Indoor placement or tiles under roofing will not fill from rain. Placing several units on a flat roof above a kitchen or bathroom is the standard base layout: rain access above, plumbing to fixtures below.

Accessing water

Interact with the collector like any other fluid container: drink directly, pour into bottles or pots, or use the fluid UI to transfer volumes. A standard plastic water bottle holds 1.0 L; a cooking pot holds 1.5 L and can also catch some rain on its own (pot rain factor 0.8).

Build 41 history (not current)

Many Build 41 guides quote small 160 / large 400 unit capacities. On Build 42.19, use the 400 L / 600 L table above instead of those older numbers.

Water purification

1. Boil on a heat source

1. Fill a cookable fluid container (cooking pot, saucepan, kettle, or other heat-safe vessel) with tainted water.
2. Light a stove, campfire, barbecue, or other heat source—prefer outdoor or ventilated setups so you do not burn the safehouse.
3. Place the container on the heat and wait until the fluid is no longer tainted.
4. Store clean water in closed bottles or clean pots. Do not pour clean water into a collector that still holds tainted rain unless you intend to re-purify the mix.

2. Water Purification Tablets (vanilla)

Build 42.19 includes a vanilla purify-water craft: keep a non-empty fluid item in hand and consume Water Purification Tablets (about 20 uses per full pack). This is a real base-game chemical route—you do not need a filter mod only for tablet purification.

Plumbing sinks to a rain collector

After city water fails, you can point indoor fixtures at an outdoor collector such as a rooftop rain barrel.

1. Place a filled (or filling) rain collector on the level above the fixture, ideally on the same tile or an adjacent tile one floor up.
2. Ensure the fixture is in a proper indoor room (walls and roof so the tile is not treated as outside).
3. Hold an unbroken Pipe Wrench in your main inventory.
4. Right-click the fixture and choose the plumb action.
5. Test by drawing water at the faucet. Plumbing does not clean the fluid—if the barrel is tainted, the tap is tainted.

Other water sources

Base water strategy

• Build at least one small collector as soon as Woodwork hits 3; upgrade or add large barrels at Woodwork 5 for drought buffer.
• Prefer tarp recipes when garbage bags are scarce; bags are still fine when you loot four at once.
• Keep a few pots or bottles of purified water indoors as a closed reserve so a dry week does not force river runs.
• Use tainted rain freely for crops and cleaning; purify only the drinking and cooking share.
• Never leave an unattended indoor campfire solely for boiling—fire risk often costs more than the water you save. Pair water work with generator power and outdoor cooking spots when possible (power and water restore guide).

Numbers at a glance

• Small crate: Woodwork 3 · 400 L · rain factor 0.4 · 4 planks / 4 nails / 4 bags or 1 tarp · +30 XP
• Large barrel: Woodwork 5 · 600 L · rain factor 0.25 · 6 planks / 5 nails / 4 bags or 1 tarp · +50 XP
• Plumb: Pipe Wrench · collector higher floor · indoor fixture · test Fill / Drink
• Safety: rain is tainted · boil or tablets · plumbing does not purify

FAQ

Related guides

• Restore power and water
• Carpentry tips and leveling
• Building walls and fortifying a base
• First-week survival
• Base location ideas