Multi-Family Housing Design

Single-family houses are material-intensive, thermally inefficient, and spread a settlement across more land than necessary. Multi-family housing—where two or more family units share walls, roofs, or common facilities—has been the norm throughout most of human history. Roman insulae, medieval row houses, Puebloan apartment complexes, and Norse longhouses all housed multiple families efficiently.

In a post-collapse settlement, multi-family housing makes practical sense: less material per family, better thermal performance, more compact settlement layout, and natural mutual aid between neighbors. But it also creates challenges: noise, privacy, and interpersonal friction. Good design minimizes the drawbacks while maximizing the benefits.

Housing Models

Longhouse

A single long building divided into family units along its length. Each family gets a section (typically 4-6m long) of the building’s full width (4-6m). Doors open to the outside; families share a common roof and potentially shared hearth.

Historical examples: Viking longhouses (up to 50m long), Iroquois longhouses (up to 100m long), Borneo longhouses.

Advantages:

Very material-efficient (one continuous roof, two exterior walls shared among all families)
Warm—each family’s fire contributes to heating the entire structure
Naturally social—shared corridor or common area runs the building’s length
Simple structural design—no complex corners or intersections

Disadvantages:

Limited privacy (especially acoustic)
If one section catches fire, the entire building is at risk
Individual families can’t expand their unit independently
Social dynamics are forced—personality conflicts have no buffer

Best for: Founding phase when materials and labor are scarce and social cohesion is high.

Row Houses (Terraced)

Individual family units sharing side walls, each with its own front and back door, its own roof section, and its own hearth/stove. Think of connected townhouses.

Advantages:

Each family has a private, self-contained unit with its own entrance
Shared walls save ~30-40% of wall material compared to detached houses
Shared walls provide fire resistance (a thick masonry party wall stops fire spread)
Each unit can be different sizes to match family needs
Good balance of community and privacy

Disadvantages:

Noise transmission through shared walls (mitigated by thick, massive walls)
Units at the ends of the row lose one shared wall’s thermal benefit
Limited natural light on the shared-wall sides

Best for: Established settlements wanting permanent, comfortable housing.

Courtyard Cluster

Multiple small housing units arranged around a shared courtyard. Each family has its own small building; the courtyard is shared outdoor space.

Advantages:

Maximum flexibility—units can be different sizes and construction types
Courtyard provides sheltered outdoor workspace, children’s play area, and social space
Each unit has exterior walls on all sides (good ventilation and light)
Easy to expand—add another unit to the courtyard edge

Disadvantages:

More material per family than row houses or longhouses
Less thermal benefit from shared walls (units may or may not share walls)
Courtyard maintenance is a shared responsibility

Best for: Established settlements with adequate materials, families wanting some independence within community structure.

Apartment-Style (Stacked)

Multi-story buildings with units on different levels. Upper units accessed by external stairs or balconies.

Advantages:

Extremely land-efficient (smallest footprint per family)
Warm—heat rises from lower units to upper units
Good defensive properties (upper floors are hard to access)

Disadvantages:

Complex structural requirements (upper floors must support significant loads)
Difficult for elderly or disabled access
Fire escape from upper floors is dangerous
Water delivery and waste management more complex at height

Best for: Settlements with limited buildable land, skilled builders, and primarily young/able-bodied population.

Private vs. Shared Spaces

Minimum Private Space

Every family (or individual without a family) needs a private space that is exclusively theirs—where they can close a door, have a private conversation, and control their own environment.

Minimum private unit sizes:

Individual: 8-12 m² (sleeping, personal storage)
Couple: 12-16 m² (sleeping, personal storage, some private living space)
Family with children: 20-30 m² (parents’ sleeping area, children’s sleeping area, storage)

These are minimums. Anything larger improves comfort and reduces friction. A family unit of 25-35 m² with their own small hearth or stove is comfortable long-term.

What Can Be Shared

Sharing facilities reduces per-family construction costs significantly:

Good candidates for sharing:

Kitchen: A shared cooking area with a large hearth serves 4-8 families. Saves fuel (one fire cooks for many) and construction (one chimney, one food prep area). Common in historical communal living
Bathing facility: A shared bathhouse with heated water is more practical than individual bathrooms. Saves water, fuel, and space
Laundry: A shared laundry area with wash tubs, a fire for heating water, and drying lines
Storage: Shared root cellar, granary, and workshop tools
Outdoor workspace: Courtyard or covered porch for food processing, crafts, social time

Poor candidates for sharing:

Sleeping space — people need acoustic and visual privacy for sleep
Toilets — hygiene requires personal responsibility. One composting toilet per family unit, not shared between families
Personal storage — each family needs secure storage for personal items, tools, and supplies

Sound Isolation

Noise is the #1 complaint in multi-family housing. Babies crying, arguments, snoring, and early risers disturb everyone through thin walls.

Design strategies:

Mass — the thicker and heavier the shared wall, the more sound it blocks. A 40cm earthbag wall blocks more sound than a 15cm timber wall. Target: shared walls at least 30cm thick with dense materials
Decoupling — an air gap between two separate wall layers blocks sound dramatically. Even a 2cm gap between two plastered walls provides significant improvement. Fill with loose insulation (straw, wool) for even better performance
Double-wall construction — for critical noise separation (between bedrooms of different families), build two independent walls with a 5-10cm gap between them. Each wall stands on its own foundation/base plate with no rigid connection to the other
Seal gaps — sound travels through any opening. Seal under doors, around pipe penetrations, and where walls meet ceiling

Thermal Advantages

Shared walls provide significant heating benefits:

A party wall (shared between two heated units) loses essentially zero heat—both sides are at similar temperatures. This eliminates the heat loss that an exterior wall would cause
A row of 6 units with shared walls has only 8 exterior wall faces instead of 24—a 67% reduction in exterior wall surface
Upper units in a stacked design benefit from heat rising from lower units—they may need significantly less fuel

These advantages are measured, not theoretical. Multi-family housing in cold climates uses 30-50% less fuel per family than equivalent detached houses.

Architecture shapes social interactions. Design intentionally:

Privacy gradient: Arrange spaces from most public to most private:

Public → shared courtyard/common area
Semi-public → front porch/entry of individual unit
Semi-private → family living area (behind a closeable door)
Private → bedroom/sleeping area (behind a second door)

This gradient gives residents control over their level of social interaction. They can choose to be social (step into the courtyard) or private (close their door) at any time.

Conflict reduction:

Avoid placing kitchens or living areas of different families sharing the same wall—the noise and activity patterns will clash
Orient entrances so families don’t look directly into each other’s units
Provide adequate storage so communal areas aren’t cluttered with personal belongings
Design clear maintenance responsibilities for shared spaces

Aging in place: At least some units should be ground-floor, step-free, and wide-doored enough for someone with limited mobility. As community members age or sustain injuries, they need housing that accommodates their abilities without relocation.

Construction Sequence

For row houses or longhouse construction:

Build shared walls first — these are the structural backbone
Add individual unit features — private hearths, internal partitions, door/window openings
Roof as one continuous structure — more weather-resistant than individual roofs
Interior finishing — each family can finish their unit to their own preference and schedule

This approach allows the community to focus effort on the critical shared infrastructure first, then individuals customize their private spaces.

Material Savings Summary

Configuration	Wall material vs. detached	Roof material vs. detached	Fuel use vs. detached
Detached house	100%	100%	100%
Row of 4	62%	85%	60-70%
Row of 6	56%	82%	55-65%
Longhouse (8 units)	50%	75%	50-60%
Courtyard cluster (6)	70-80%	90%	70-80%

The material savings are substantial—especially in a world where every timber must be felled by hand and every brick made from scratch.

Explorer

Multi-Family Housing Design