Wall

This article is about the constructable building only. For natural and smoothed walls, see Structure.

Walls are impassable structures primarily used to create rooms.

Acquisition

Walls are built and repaired by colonists assigned to construct. Walls are constructed with 5 Stuff (Metallic/Woody/Stony, 50 for SMVs) and take 135 ticks (2.25 secs) to build.

Wall construction may sometimes fail and waste the materials, more often with lower construction skill.

Summary

Walls are impassible objects that block movement, line of sight, and line of fire. An area enclosed by walls, doors, or other impassible objects like coolers is considered a room. Each room has its own room stats - consisting of cleanliness, beauty, wealth, and spaciousness. Power conduits can be constructed below a wall, negating the conduit's beauty penalty. Floors under a wall are also negated for room stats.

Walls can also support roofing, up to 6 tiles away in all directions. If walls, columns, and all other supporting objects are removed, then the roof will collapse and injure pawns and objects below. While most natural walls count as walls for the purposes of rooms, collapsed rocks do not.

Corners, i.e., diagonal walls, are not required to complete a room. Corners will provide weaker temperature and beauty insulation than vertical or horizontal aligned walls, but still create rooms. Pawns cannot travel or attack through diagonal gaps. However, fire can go through diagonals.

Walls also provide excellent cover from projectile attacks, blocking 75% of shots. Pawns behind a wall with an adjacent free space will "lean" around the wall to shoot at enemies on the other side.

Special

Certain damage types are designed to deal more damage to impassible terrain, and to walls specifically:

Walls take 8× damage from Bomb type damage; 4× from being an impassable, and 2× for being a wall
Walls take 30× damage from Thump type damage; 15× from being an impassable, and 2× for being a wall
Walls take 7.5× damage from Breach type damage; 10× from being impassable, but 0.75× for being a wall

Meditation

Ascetics can meditate at a wall for a Meditation Focus Strength of 22%.

Analysis

Walls, or natural rock, are practically essential to every colony. It's certainly possible to create room of doors or coolers, and use other forms of defences, but it thoroughly impractical for a variety of reasons. As impassible structures, they are important when controling enemy flow and creating defences, be they basic curtain walls or to elaborate killboxes. Sapper and breach raids will explicitly try and break them, but other raiders will path around so long as any target can be reached.

Note that non-sapper, non-breacher raiders will occasionally ignite or throw grenades or Molotovs at walls. These are infrequent and random - they won't intentionally attempt to breach a wall, but if the wall is destroyed by a single explosion or the resulting fire, they will path through the breach. As such, walls that are non-flammable and have over 400 HP to resist the damage from standard explosives should be used for defenses, even when only routing standard raiders. Ideally, these walls would be also be two thick.

Material choice

Wall materials each have their own advantages and disadvantages:

Wood

Wood is easily obtainable in a vast majority of biomes, and are the fastest wall to create. They are very helpful when first starting a Crashlanded scenario, and often essential for Lost Tribe and Naked Brutality starts. However, wood is flammable. Other than raiders lighting it on fire, a bad dry thunderstorm or conduit explosion could end up engulfing your entire base in flames. Especially by the time you get to using Electricity, you should replace wood with another material.

Stone

Stone is very abundant, but very time consuming. In addition to constructing the wall, cutting up stone blocks takes quite a bit of work. However, stone types are available in bulk, generally fairly hardy and are completely fire-proof. Ideally, all large walls should be made of one of the more durable stone types however strategically placed sections of stone walls will act as a "fire break" to limit the spread of a fire while your colonists fight it.

Granite is the most durable wall material. Limestone is the 2nd most durable. Limestone has no advantage as walls over granite, unless your biome happens to lack the harder stone.
- Note that breachers, one of the most relevant cases of wall durability, can break any stone wall in the same amount of hits.
Sandstone walls are the quickest stone wall to build, which can save a lot of time for large bases. They are also the weakest stone type able to resist a single standard 50 damage explosion without failure, while no material short of plasteel can resist two. This makes Sandstone the lowest acceptable tier for outer walls, mortar pits, unstable power cell enclosures, and similar defences.
Slate has essentially no redeeming qualities compared to other stone types. They are destroyed by a single explosion and their benefits of being lighter as when in material form is rarely relevant. They are still stronger than steel and wood, and are non-flammable, but they should only be used when other, stronger stone types aren't available.
Marble walls give +1 beauty to a room and colonists looking at it. Since even a normal marble small sculpture provides 68 already while requiring only ten times as much material it is usually more beneficial to craft sculptures instead. They are otherwise the least durable stone wall.

Metal

In comparison to stone, steel is less durable and flammable. However, steel is much faster to construct. It may also be a necessity in a material-scare biome like the ice sheet. Overall, steel walls are useful as a quick installation or when nothing else is available, but the other demands on steel supplies and the relative fragility of the resulting walls make them a poor choice in most circumstances.

Plasteel and Uranium make for the two strongest walls in the game and are non-flammable, but these materials are significantly rarer and more expensive than other alternatives. As such they should be reserved for locations that need to take a lot of damage without failure, such as the entrance, back wall, and defenses of a killbox.

Precious materials

Not technically a category in-game gold, silver, and jade walls are similar in that they are significantly more beautiful than regular walls while offering very low HP. Whether you should invest your precious materials in walls or sculptures depends on the expected quality of the sculpture and how many rooms the walls are facing.

The increase in wealth of ten walls facing

One room is inferior to a small sculpture of at least normal quality,
Two rooms is inferior to a small sculpture of at least masterwork quality for silver and jade and none for gold,
Three rooms is inferior to a small sculpture of at least legendary quality for silver and masterwork quality for jade,
Four rooms is inferior to a small sculpture of at least legendary quality for silver and jade.

The increase in beauty of ten walls facing

One room is inferior to a small sculpture of at least normal quality for gold and silver and poor quality for jade,
Two rooms is inferior to a small sculpture of at least good quality,
Three rooms is inferior to a small sculpture of at least excellent quality for gold and jade and good quality for silver, and
Four rooms is inferior to a small sculpture of at least masterwork quality for gold and excellent quality for jade and silver.

Further advantages of walls are, however, that they don't reduce the room size and do not rely on having an artist.

Stats table

Wall	Beauty	Work to Build	HP	Flammability	Market Value
Material	Beauty	Work to Build	HP	Flammability	Market Value
Bioferrite	0	000,338 ticks (5.63 secs)	600	75%	4.95
Gold	20	000,122 ticks (2.03 secs)	180	40%	500
Granite blocks	0	000,950 ticks (15.83 secs)	510	0%	7.9
Limestone blocks	0	000,950 ticks (15.83 secs)	465	0%	7.9
Marble blocks	1	000,883 ticks (14.72 secs)	360	0%	7.7
Plasteel	0	000,297 ticks (4.95 secs)	840	0%	46
Sandstone blocks	0	000,815 ticks (13.58 secs)	420	0%	7.4
Silver	6	000,135 ticks (2.25 secs)	210	40%	51
Slate blocks	0	000,950 ticks (15.83 secs)	390	0%	7.9
Steel	0	000,135 ticks (2.25 secs)	300	40%	10
Jade	10	000,675 ticks (11.25 secs)	150	0%	27
Uranium	0	000,257 ticks (4.28 secs)	750	0%	31
Wood	0	000,095 ticks (1.58 secs)	195	100%	6.3

Version history

0.7.581 - Wood wall and metal wall merged into wall with the introduction of the stuff system.
1.1.0 - Terrain requirements now depends on what they’re built from. This means stone walls can’t be built on bridges any more.
1.1.2654 - Increase psyfocus gain of wall from 11 to 22.
1.3.3067 - Metallic walls now use stuff-specific UI and blueprint graphics.
1.3.3117 - Added a "build door" gizmo that displays when a wall or wall blueprint is selected.
1.3.3200 - Thump damage multiplier versus walls reduced from 4× to 2×.

Architect

Structure: Animal flap • Autodoor • Bridge • Column • Door • Fence • Fence gate • Ornate door • Wall • Security door
Related: Roof