Sierra Builders GuildVolunteer
Seven Sierra Builders Guild volunteers standing behind the stone arch bridge they are building among manzanita trees, with the plywood arch form still in place
Guild crew on a stone arch bridge build

Nevada County, California

Learn to build what outlasts the fire.

The Sierra Builders Guild trains volunteers in hands-on construction skills, then puts them to work on fire-resilient housing, water storage, and trail infrastructure for our foothill communities.

Join a workshopSee what we build

Our Mission

To provide education, networking, and resources to community members who share an interest in creating safer and more meaningful connections with the land they live on.

Join us if you are

  • Land owners
  • Licensed contractors
  • People curious about alternative building techniques
  • Aspiring apprentices
  • Journeyman builders

Our Vision

To support and grow an institution that develops fire safe and resilient shelters and homes through a collaborative community effort.

About the Guild

A community of builders, shaped by the foothills.

Founded by craftsman Zachi Anderson, the Sierra Builders Guild brings neighbors together to share building skills. It supports new ideas in fire-resilient, off-grid, and alternative construction across Nevada City, Grass Valley, and the rest of Nevada County.

A round fieldstone tower with a sculpted cement mushroom-cap roof and arched doorway, set among pines

  • Build for fire country

    Ferro-cement shells, earth-sheltered and underground homes, on-site water storage, and defensible perimeters. We teach construction that gives a structure a real chance when wildfire comes through.

  • Learn by doing

    No lecture halls. Volunteers learn alongside experienced craftspeople on real projects, from the first mix of mortar to the last stone set in an arch.

  • Give it back to the land

    Retaining walls, stone arch bridges, and trail features help keep our trails open and our hillsides in place for years to come.

The crafts

Stone, steel, cement, and water.

The skills we teach are the ones that let a building, or a trail, take a hard season and keep standing.

  • Ferro-cement

    Fire-resistant domes, shells, and earth-sheltered homes

  • Stone masonry

    Retaining walls, stone arch bridges, and steps

  • Water storage

    Cisterns and tanks for fire defense and dry summers

  • Trail infrastructure

    Drainage, crossings, and trail features

  • Metalwork

    Armatures, rebar cages, and hardware for the build

  • Concrete & mortar

    Mixing, application, and curing that holds up for decades

Looking down into a sculpted ferro-cement planter well lined with soil pockets, plants, and spiral drip irrigation

What construction looks like

Red dirt, grey stone, and a lot of hands.

A volunteer setting rust-colored stones on a tiered dry-stacked retaining wall in front of an earth-sheltered home
Dry-stone terraces. Hand-set retaining walls step the hillside down to the drive.

A look at recent guild builds, from breaking ground to the finished arch.

A builder standing beside a white ferro-cement dome wall, with corrugated drain pipe and filter fabric laid along the trench
Drainage first. Waterproofing, filter fabric, and perforated pipe go in before a single shovel of backfill.
Two builders shoveling red dirt from a wheelbarrow into a trench beside a ferro-cement wall, with a skid steer behind them
Backfill. Red dirt goes back against the shell, one wheelbarrow at a time.
A freshly poured concrete patio scored in a curving grid, winding through a wooded yard toward a cement mixer
Hand-scored pathway. Fresh concrete tooled into curving pavers that follow the garden beds.
Guild volunteers hauling buckets of mix from a cement mixer beside a curved ferro-cement wall
Mix day. Buckets of cement move from the mixer to the wall by hand.

Ferro-cement projects

Built into the hillside, built to last.

An earth-sheltered ferro-cement home with sculpted retaining walls and hand-set stone terraces. Every wall, arch, and stone came from guild hands.

The arched white entry tunnel of an earth-sheltered home, flanked by potted cacti beneath oak trees
Arched entry. A double-arch tunnel leads down into the sheltered living space.
Curving white ferro-cement planter walls around an oak tree, with an arched entry and stacked stone terraces beside an earth-sheltered home
Earth-sheltered home. Ferro-cement shell, sculpted retaining walls, and dry-stacked stone terraces.
Steel rebar and expanded metal lath forming the armature of a flared column and dome before plastering
The armature. Rebar and metal lath shape every curve before any cement goes on.
A craftsman in gloves hand-packing cement onto the curved interior wall of a ferro-cement room beside an arched opening
Hand-packed interior. Cement pressed into the lath by hand, smoothing the inside of an arch.
Workers troweling the gray interior of arched alcoves set into a sculpted ferro-cement wall finished to look like banded sandstone
Sculpted sandstone finish. Banded, hand-carved facade while the crew trowels the alcoves inside.
A crew spraying cement onto a large circular rebar-reinforced tank wall lined with white membrane, with a central column, in an oak forest
Water tank pour. A big crew shoots cement onto a round, rebar-reinforced tank wall.
Four cheering crew members standing beside newly finished terraced ferro-cement raised garden beds filled with soil and gravel paths
Terraced garden beds. Finished raised beds and steps, and a happy crew.

Stone Arch Bridges

Hand-set arches that carry our trails over creeks and gullies, built to stand for generations.

A finished stone arch bridge with a red-earth deck and curving dry-stone walls on a foothill trail
Foothill trail arch. Finished, backfilled, and ready for foot traffic.
A mortared fieldstone arch footbridge spanning a shaded creek, framed by ivy and oak trunks
Fieldstone footbridge. A single mortared arch carries the trail over a seasonal creek.
A grey-green stone arch bridge resting on granite boulders over a small forest creek
Boulder-founded arch. Stone voussoirs sprung from native granite boulders in the creek bed.

Trail Projects

Cutting, grading, and maintaining the foothill trails our community walks every day.

A guild member in a wide-brimmed hat operating a red mini excavator, digging into red soil among pines
Site prep. Clearing roots and cutting grade before the stone goes in.
A red dirt trail curving beneath manzanita branches through autumn brush
The trails we serve. Built and maintained by guild volunteers.
A builder in a cap sculpting a ferro-cement trail railing shaped like a twisting tree branch on arched legs, in an oak and manzanita forest
Sculpted trail railing. Ferro-cement hand-carved to read like a fallen branch along the path.

Workshops & events

Learn with your hands.

We hold hands-on sessions around Nevada City and Grass Valley throughout the year. Dates and locations go up in our Facebook group first.

See upcoming events(opens Facebook in a new tab)
  • Workshop

    Stone masonry for trails & property

    Set stone for walls, steps, and arches, and learn how to read and split the rock.

  • Workshop

    Ferro-cement construction

    Tie mesh over an armature, then apply and cure cement for thin, strong, fire-resistant shells.

  • Build day

    Community project builds

    Put new skills to work on fire-resilient housing, water storage, and trail projects around the county.

  • Gathering

    Guild socials

    Meet other builders, swap techniques, and hear what is coming up next.

Get involved

There's room for every pair of hands.

Volunteer

No experience needed. Show up for a build day, bring gloves, and learn alongside the crew.

Apprentice

Work with experienced craftspeople over many projects and grow from helper to builder.

Support

Donate materials, tools, or funds, or suggest a project in your community.

A guild volunteer setting river stones into a mortared wall beside a ferro-cement form

Join the Guild

Come build with us.

Join the Sierra Builders Guild group on Facebook for workshop dates, build days, and project updates, or call to talk with someone about getting started.

Join the Facebook group(opens in a new tab)(530) 270-9250