Home / Materials and parts
Materials and parts
A first-build shopping list for approved design C. Tax, delivery and tools are not included.
Prices live in build/prices.js and were checked 2026-10-12 against the research pages under research/buying/. A line that shows a “was” price is one the research made cheaper. Every total on this page is computed from that file. See the price breakdown and build phases.
Have an experienced trailer fabricator approve the frame, axle placement, welds and tongue. Have licensed trades inspect propane and 120-volt work. Follow each maker's instructions and protect every wire and pipe from heat, edges and road damage.
A unit price is the price of one listed unit. “Allowance” means an exact-size listing was not found. Confirm dimensions, shipping and stock before buying. The axle-kit row is counted once. Its included parts appear again at zero cost only to make the checklist complete.
Words used here
- 11 ga / 16 ga
- Eleven-gauge and 16-gauge describe steel wall thickness. A smaller gauge number is thicker.
- VHB
- Very high bond (VHB) is structural double-sided acrylic foam tape.
- PEX
- Cross-linked polyethylene (PEX) is flexible drinking-water tubing.
- LiFePO4
- Lithium iron phosphate (LiFePO4) is the battery chemistry.
- TT-30
- Travel-trailer 30 amp (TT-30) is a 120-volt campground connection.
- MRBF
- A marine-rated battery fuse (MRBF) protects the heavy battery cable.
- DOT
- U.S. Department of Transportation (DOT) markings show that a road-light or tire was made to an applicable federal standard.
1. Frame and running gear
Welding wire and shielding gas belong in Tools, not this list. The axle is custom-sized. Confirm hub-face, spring-center, camber direction and brake orientation before ordering.
2. Floor and body
3. Plumbing and tanks
4. Propane
5. Electrical: 12 V and 120 V
6. Comfort appliances
7. Interior
Later — outside the first-build total
These parts preserve the approved future plan. None is included in the first-build grand total.
How I counted
| Material | Calculation |
|---|---|
| Frame tube | 2 × 18 ft main rails + 2 × 91 in ends + 2 × √(60² + 48²) in tongue members = 64.0 ft of 2 × 4. Eight × 91 in = 60.7 ft of 2 × 2. |
| Wall and roof tube | Side perimeters 98.3 ft + side studs at 24 in 105.3 ft + end perimeters 58.3 ft + end studs 39.5 ft + roof side rails 36 ft + ten 8 ft rafters 80 ft + opening perimeters 59.1 ft = 476.5 ft. Buy 24 × 20 ft. |
| Wall and roof sheet area | Two 216 × 79 in sides + two 96 × 79 in ends + 216 × 96 in roof = 486.3 sq ft. Door, four windows, 14 × 14 in vent and 14.25 × 14.25 in air-conditioner openings = 32.0 sq ft. Net = 454.3 sq ft. |
| Aluminum sheets | Net area is 14 sheets, but rectangular face layout controls: 6 per side, 2 per end and 6 on roof = 22 sheets. Offcuts cover small areas and trim tests. |
| VHB contact | The 476.5 ft wall/roof framing estimate is the first tape-contact estimate. 476.5 ÷ 108 ft per roll = 4.4, so buy 5 rolls. |
| Interior plywood | Zone footprints produce about 71 sq ft of load surfaces, so buy 3 sheets of 3/4 in. Listed cabinet widths, depths and heights produce about 150 sq ft of faces and sides, so buy 5 sheets of 1/2 in. Make a cut plan before purchase. |
Design numbers
| Weight number | Amount | Basis |
|---|---|---|
| Raw structural steel bought | 1,192 lb | Supplier tube-weight chart and the design cut list. |
| .030 aluminum bought | 303 lb | Supplier sheet weight and the design. |
The honest first-build number is over the cap. The materials total is above the $10,000 cap before tools, tax and delivery. Do not hide that gap by deleting brakes, alarms, road lights, fuses or propane safety parts.