Smoking is the preservation method that does three things simultaneously: it removes moisture from the surface and outer layers of food, it deposits antimicrobial compounds from wood smoke (creosote, phenols, and aldehydes) that inhibit bacterial and fungal growth, and it seals the surface with a thin resinous layer that slows further moisture exchange with the environment. The combination makes smoked food shelf-stable at room temperature for days to weeks without refrigeration — a preservation tool that requires no electricity, no jars, no special equipment beyond a fire, green wood, and a structure to contain the smoke.
The full smoking post in the Field Rations Archive covers the preservation science, food preparation, brine ratios, and process in detail. This post covers the builds — how to construct improvised smoking structures from available materials at three scales: a simple single-use smoke box for small batches, a barrel smoker for regular household use, and a permanent smokehouse for serious preservation volume.
SMOKE TYPES AND TEMPERATURES
Two smoking methods exist and they are not interchangeable in function or outcome:
Cold smoking (60-90°F): Smoke without significant heat. Preserves and flavors without cooking. Used for fish, cheese, cured meats, and sausages that have already been salt-cured. Cold smoking alone does not kill pathogens — the food must be salt-cured first. Cold smoking adds the antimicrobial surface treatment and flavor after curing. The food is not cooked by cold smoking.
Hot smoking (180-275°F): Smoke with enough heat to cook the food while smoking. Kills pathogens, removes moisture, and deposits smoke compounds simultaneously. Used for whole fish, poultry, pork ribs, brisket, and most foods smoked without prior salt curing. The product is cooked through and smoke-preserved. It does not last as long as cold-smoked and salt-cured product but requires less preparation.
Know which method you are using before building — cold smoking requires maintaining very low temperatures, which requires separating the heat source from the food by distance or design. Hot smoking allows the heat source and food to be in closer proximity.
Wood selection: Hardwoods only — softwoods (pine, fir, spruce, cedar) contain resins that produce unpleasant and potentially toxic smoke. Fruit woods (apple, cherry, plum, peach) produce mild, sweet smoke appropriate for fish, poultry, and pork. Oak and hickory produce heavy, strong smoke appropriate for beef and game. Alder is the traditional smoke wood for fish in the Pacific Northwest. Maple produces moderate smoke suitable for most applications. Use dry, seasoned wood — green wood produces more smoke but less heat and more water vapor, which can create surface moisture issues on cold-smoked product.
BUILD 1 — SIMPLE SMOKE BOX
Single-use or occasional use. Materials on hand. No permanent construction.
A smoke box is any enclosed or semi-enclosed structure that contains smoke around food for a sufficient period. It does not need to be airtight, perfectly constructed, or aesthetically pleasing. It needs to keep smoke in contact with the food and keep the rain off.
Cardboard box smoker (cold smoking only): A large cardboard box — appliance box, moving box — serves as a cold smoker for a single batch. Cut ventilation holes near the top on two sides. Hang or rack food inside using skewers, wire, or clean string through holes punched in the box sides. Place a metal tray with smoldering wood chips on the ground outside the box; route smoke in through a small hole at the bottom of one side via a short length of flexible aluminum dryer duct or simply by placing the box over the smoke source at a distance — position the box downwind of a small smoldering fire with a channel of boards directing smoke into the box bottom.
Cardboard is flammable — the smoke source must not have open flame and must not contact the box. Cold smoking only. A smoldering pile of wood chips with no visible flame is the correct smoke source for a cardboard box smoker.
This is a one-use system appropriate for an immediate need. It is not a long-term solution but it works and costs nothing beyond what is already on hand.
Wooden crate or pallet wood box: Same design as the cardboard box smoker but constructed from pallet wood or any available lumber. More durable, can be used for hot smoking at low temperatures, can be reused. Build a simple box frame from pallet boards with a loose-fitting lid. Hang food from the top interior. Place a cast iron pan or metal tray of smoldering wood chips on the floor of the box with a small rock or spacer to allow air circulation under it. This is hot smoking — the chips and restricted airflow produce both heat and smoke. Vent through gaps in the lid construction.
BUILD 2 — BARREL SMOKER
The standard. Reusable, scalable, adequate for household preservation batches.
A 55-gallon steel drum — the same barrel used for water storage, available at farm supply stores and through the same Craigslist/Facebook Marketplace sources — makes an excellent smoker. Steel handles heat well, the volume accommodates meaningful batch sizes, and the drum’s existing structure provides the container with minimal modification.
Materials:
- 1 clean 55-gallon steel drum — must be clean and uncontaminated. Drums that previously held food ingredients are ideal. Avoid any drum with chemical residue. If the drum had any non-food content, burn it out completely with a hot fire inside before use and allow to cool and air out thoroughly.
- Drill with metal bits and hole saw.
- Angle grinder or reciprocating saw — for cutting the door opening (optional).
- Steel expanded metal or wire mesh — for food grates inside the drum.
- Metal rod or rebar — for hanging food.
- Bolts or metal screws — for securing grates and rods.
- Thermometer — a grill thermometer with probe through the drum wall is useful but not required.
Vertical drum smoker (most common configuration): The drum stands upright — vertically. The firebox is at the bottom, the food is in the upper portion, heat and smoke rise naturally.
Cut or drill ventilation holes near the base of the drum — 4-6 holes, 1 inch diameter, evenly spaced around the circumference at 2-3 inches from the bottom. These are the air intake for the firebox. Install a sliding damper over each vent (a piece of metal with a bolt as a pivot point) if precise temperature control is desired — or simply partially cover with flat rocks for a simpler approach.
Cut an access door in the lower side of the drum — approximately 8×10 inches — for adding wood and managing the fire without lifting the lid. Use a reciprocating saw or angle grinder. Attach the cut-out panel back as a door using a bolt hinge and a bolt latch. This is not a precision operation — a functional door that opens and closes is the goal.
Install two or three grate levels in the upper portion of the drum using expanded metal cut to circle shape, supported by bolts through the drum wall at the appropriate height. Space grates 6-8 inches apart vertically. The lowest grate should be at least 18-20 inches above the firebox floor to allow adequate heat dissipation for lower-temperature smoking.
Drill 4-6 holes near the top of the drum for a rod to hang fish, sausages, or other items on hooks or string.
The drum lid serves as the smoker lid — it sits on top during use and can be propped slightly for venting or weighted down for heat retention.
Horizontal drum smoker (offset firebox): A more advanced configuration that separates the firebox from the cooking chamber — better for low-temperature smoking and for large volumes of meat. Two drums: one horizontal as the cooking chamber, one vertical or horizontal as the firebox, connected by a short duct at the firebox end of the cooking drum. Smoke and heat travel horizontally through the cooking chamber and exhaust through a stack at the far end.
This design allows precise temperature control — the distance between firebox and cooking chamber, combined with dampers on both ends, allows fine adjustment of temperature and smoke density. It is the configuration used in professional BBQ smokers and produces the most consistently managed results. More complex to build but not beyond an afternoon of work with basic metalworking tools.
Operating the barrel smoker: For hot smoking: Build a small fire of hardwood in the firebox. Allow to burn down to hot coals before adding the food — cooking over active flame produces bitter, acrid smoke. Maintain temperature with small additions of wood. Monitor with a thermometer.
For cold smoking: Build the fire outside the drum and route smoke in via the lower vent holes while maintaining very limited airflow — the goal is smoke with minimal heat. Bank the fire heavily with green wood or wood chips to produce maximum smoke at minimum combustion temperature. Check temperature frequently — above 90°F the cold smoking process crosses into partial cooking.
BUILD 3 — PERMANENT SMOKEHOUSE
For serious preservation volume. Seasonal or year-round use. Built to last.
A smokehouse is a purpose-built structure — typically 6×6 to 8×8 feet, 7-8 feet tall — dedicated to smoking large quantities of food. It is the infrastructure that supports preservation at the scale of a productive homestead: whole hogs, sides of beef, quantities of fish sufficient for winter storage, batches of sausage and cured meats sufficient to feed a household for months.
Site selection: The smokehouse should be downwind of living structures — on a prevailing downwind site so smoke exhausts away from the house. Minimum 30 feet from any structure. On level, well-drained ground. Accessible from the kitchen and processing area.
Construction: Frame with 4×4 posts and 2×4 wall framing on 16-inch centers — the same basic framing as any small structure. Wall sheathing can be board and batten, rough-sawn lumber, or any available sheathing. The walls do not need to be insulated or finished — they need to contain smoke. Gaps and imperfect seaming are acceptable as long as the structure is weathertight overhead and does not leak significant smoke from the lower walls during use.
Roof: a simple gable or shed roof with metal roofing — metal handles the heat and smoke exposure better than shingles long-term. Install a ridge vent or a small cupola at the peak for smoke exhaust. The exhaust point should be closeable — a sliding damper at the ridge vent allows temperature and smoke retention to be controlled.
Interior: Install horizontal hanging poles across the full width of the structure at 4-foot and 6-foot heights — for hanging whole animals, sides, or large batches of fish. Install 2-3 removable wire grate shelves for smaller items. The interior should be accessible on all sides from within the structure.
Firebox: The firebox can be inside the smokehouse at floor level (traditional, simpler) or outside with a buried smoke channel running into the smokehouse floor (allows cold smoking at very low temperatures without any heat from the fire reaching the chamber).
Inside firebox: A simple brick or concrete block firebox in one corner of the structure, with a cast iron door or metal plate as the stoking access. A metal smoke diffuser plate above the firebox prevents direct flame contact with food. Adequate for hot smoking. Cold smoking requires careful fire management to minimize heat.
Outside firebox with buried channel: Dig a trench from the firebox location to the smokehouse floor entry point — typically 6-10 feet long, 12 inches deep, covered with flat stones or metal sheet. The fire burns in a pit at the far end; smoke travels through the trench and enters the smokehouse cool. This is the traditional cold smoking design used for fish and sausage preservation and produces consistently low temperatures regardless of fire size.
Capacity: A 6×6 smokehouse with hanging poles at two heights can handle an entire hog broken into sections, 50-100 lbs of fish, or several hundred lbs of sausage in a single batch. This is the preservation volume that moves the household food supply from months to a full year of protein.
QUICK REFERENCE — BUILD COMPARISON
| Build | Cost | Time | Batch Size | Hot Smoke | Cold Smoke | Durability |
|---|---|---|---|---|---|---|
| Cardboard box | $0 | 15 min | 2-4 lbs | No | Yes | Single use |
| Pallet wood box | $0-10 | 1-2 hrs | 5-10 lbs | Low temp | Yes | Seasonal |
| Barrel smoker (vertical) | $20-60 | 2-4 hrs | 10-30 lbs | Yes | With care | Years |
| Barrel smoker (offset) | $40-100 | 4-6 hrs | 20-50 lbs | Yes | Yes | Years |
| Permanent smokehouse | $300-800 | 2-3 days | 100+ lbs | Yes | Yes | Decades |
FINAL THOUGHTS
A smoker is the preservation infrastructure that converts a successful hunt, a productive fishing trip, or a butchering day into months of shelf-stable protein. The barrel smoker is the correct starting point — meaningful capacity, modest cost, buildable in an afternoon, adequate for everything short of whole-animal preservation. Build it before you need it. Use it before you need it. The first smoked batch is a learning experience best had when the food is not the only food.
The smokehouse is the long-term investment that makes sense when the homestead is producing more animal protein than the barrel smoker can process. Build the barrel. Learn the process. Build the smokehouse when the volume requires it.
For the full smoking preservation process — salt curing, brine ratios, food preparation, and food safety — see Smoking in the Field Rations Archive. For the salt curing that precedes cold smoking, see Salt Curing in the Field Rations Archive. For storing smoked product in the correct conditions, see Root Cellar Build in DIY Schematics.