Barrel Composting Toilet System:
MATERIALS AND COST ESTIMATE IS FOR A 3 BARREL SYSTEM, SIZED FOR 2 ADULTS IN FULL-TIME USE
55 GALLON POLYETHYLENE BARRELS, NEW, BLACK
BARREL TOP ASSEMBLY (FOR ACTIVE BARREL):
¾” X 2’ x 2’ HARDWOOD PLYWOOD (SEE BOTTOM OF CONSTRUCTION
TOILET SEAT ASSEMBLY:
WOOD TOILET SEAT, ROUND
3” ABS SANITARY TEE, HUB X HUB X HUB $ 6
LOCATOR BOLT ASSEMBLY:
¼” X 2-1/2” CARRIAGE BOLTS, STAINLESS STEEL $ 4
HOLD-DOWN SPRING ASSEMBLY:
1-1/2" LONG SCREW EYES
3’ X 3’ FIBERGLASS INSECT SCREEN $ 6
RAIN COVER (FOR 2 AGING BARRELS)
2’ 3” X 2’ 3” CORRUGATED STEEL ROOFING PANEL $ 10
1 QUART CANNING JAR, WIDE MOUTH
--1 COMPOST CRANK $43
COMPOST CRANK RECEPTACLE:
--1 4” X 30” ABS PIPE $10
FOR 3 BARREL SYSTEM USING ALL NEW MATERIALS = $327
|Notes on materials: All materials except the barrels and the Compost
Crank and alternate tops (aluminum and concrete) can be found at major building supply centers. It's often easier to find the springs and stainless steel fasteners at hardware stores. |
--Barrels: 55-gallon high-density polyethylene barrels as described on these web pages are the commonly available type with top intact and two bung holes in the top. Metal barrels will corrode and should not be used. Polyethylene barrels with removable tops can be used, but will require a toilet top assembly different than that described here. For UV protection, barrels should be black if used in an outdoor installation. Or, barrels can be painted black with 3 coats of black oil-base enamel. Used barrels are often available at dairies and bakeries for about $15 apiece, reducing the above cost estimate by approximately $35 per barrel. However, in the event this design is eventually permitted by regulatory authorities, used barrels might not be allowed under a permit.
--Plywood top: Hardwood plywood is available in 2' square pieces at major building supply centers. Plywood with hardwood exterior veneers is recommended as it is more resistant to surface checking than softwood veneers. NOTE: See bottom of Construction
and Installation Manual for alternative top material suggestions.
--Toilet seat: Plastic seats are difficult to seal with weatherstrip to prevent insects from entering the active barrel. Wood seats are much easier to effectively weatherstrip.
--Weatherstrip: Should be closed-cell foam to prevent absorption of urine and consequent odors.
--Rain cover: Two 2" x 8" x 16" patio blocks per rain cover are minimum. 3-4 should be used in windy locations.
--Compost Crank: Can be found online at this link. We have tried a variety of other compost aeration tools, but none is as effective as the Compost Crank. The Compost Crank is an essential component of the Barrel Composting Toilet system and we do not recommend substitutes. (We do not sell this tool or have any financial connection with Lotech Products, the manufacturer of this product.)