Saving weight on your Tiny House build:
One of the most important goals of designing a tiny house is saving weight. One should choose each appliance carefully with weight a top consideration. In addition, certain building materials should be avoided.
Visit my web page for overweight THOW nightmares.
Stay away from things like concrete or granite counter tops (1.5″ thick 18.75 lbs./sq.ft), cast-iron bathtubs (1000 lbs.), and asphalt shingles. A “Farm-House” sink can weigh 200 lbs. You need to be willing to compromise your pet design aspects for saving weight.
Overlooked Weight Savings:
Traditional framing uses lots of lumber. Jesse Burke saved over 1000 pounds by sheathing the inside of the “smart framing” with 3/8 plywood on the inside instead of the outside. It’s glued and nailed every six inches to provide the shear strength needed. The windows and doors are aligned with framing members to avoid having to add additional supports. After insulating with rigid insulation the house is wrapped in Tyvek® before receiving light weight aluminum siding. The interior walls are finished with an acrylic based trowel on finish
For more information on weight saving framing materials check out my website page Framing Types.
Skip the sub-floor with the right trailer
A custom made tiny house trailer can act as a firm foundation without needing to add additional sub-floor. The cross members are properly spaced for flooring and the bottom of the trailer has an aluminium face to stop any pests or water incursion. Simply fill with insulation and apply flooring.
Choosing the right building materials:
Building materials weight tables are available on the Internet in many different forms. Just search for “building materials weights.” Usually these tables give you the weight in pounds per square foot (PPSF). Depending on how you want to calculate your tiny house weight you might prefer to know how much each piece of lumber weighs.
Plywood can be purchased in varying qualities. Plywood, good on one side, is smooth and has less blemishes. Birch plywood is quite nice. When stained it makes a very pleasing interior.
1/4 inch: 22.72 pounds per 4×8 sheet
3/8 inch: 33.92 pounds per 4×8 sheet
1/2 inch: 45.44 pounds per 4×8 sheet
5/8 inch: 56.64 pounds per 4×8 sheet
3/4 inch: 68.16 pounds per 4×8 sheet
OSB (oriented strand board) is the plywood you see that looks like it’s made out of wood chips glued and pressed into shape. It’s less expensive than plywood but weighs about two pounds more per sheet. I see it being used regularly on tiny house builds. If you use forty sheets that,s eighty extra pounds.
Gypsum Wallboard (sheetrock)
3/8 inch: 49.92 pounds per 4×8 sheet
1/2 inch: 66.56 pounds per 4×8 sheet
5/8 inch: 83.2 pounds per 4×8 sheet
Sheet rock is heavy. It’s basically a rock dust squeezed between two pieces of paper. I never recommend it’s use in a THOW. Besides being heavy, the movement during towing will cause these panels to disintegrate around each screw and the joints between panels will crack apart. These are good for regular homes but not right for a Tiny House.
Tiny House Total Weight:
Once you’ve completed your tiny house build you will want to have it weighed so you know exactly how much weight in furnishings you can have. You will be glad you scrimped and saved every pound during the build stage.