Skeleton of a tiny home
Every cabin starts with a skeleton.
Get the skeleton right and every phase after it goes smoother. Get it wrong and you pay for that mistake in the walls, the roof, the finishes, and the resale.
So wood or steel?
Here is how I think about it.
Wood Framing
Wood is the default for a reason.
It is cheap, it is fast, and every framing crew in America already knows how to build with it.
The workhorse is dimensional lumber. Your 2x4 and 2x6 studs. When you need more strength you step up to engineered wood. LVL (laminated veneer lumber) for headers and beams. Glulam for exposed spans. I-joists for floors. LSL for rim board. You tie it all together with Simpson Strong-Tie hangers and connectors.
What I love about wood:
It is the lowest cost per square foot to frame.
Any local crew can build it. No specialists required.
It is forgiving. You can change things on site with a saw and a nail gun.
It insulates itself. Wood barely conducts heat, so you get very little thermal bridging.
What keeps me up at night with wood:
It rots. Moisture is the enemy, and micro-resort sites are often wet and wooded.
It burns.
Termites and carpenter ants love it.
It warps, cups, and twists as it dries and moves.
Your clear spans are limited before the engineering gets expensive.
Steel Framing
Steel is not one thing. It is two.
The first is light-gauge steel, also called cold-formed steel or CFS. These are studs and joists rolled from thin sheet steel. They can be panelized and shipped to your site ready to stand up. It is a natural fit for prefab and for guest units that get transported.
The second is structural steel. The heavy stuff. Hot-rolled I-beams and columns, sometimes called red iron. This is what you use when you want a long open room, a big cantilever, or a wall of glass with nothing holding it up in the middle.
What I love about steel:
It does not rot, burn, warp, or feed termites.
It lasts. A steel frame does not degrade the way wood does, so the cabin you build today is still sound years from now. Longevity for your asset is a big plus.
It is lighter than you think. Pound for pound, light-gauge steel gives you the same strength with less weight. If you are putting your cabin on a trailer, and naturally you will be conscious about weight, that lighter frame can be another reason to go steel.
It is dimensionally perfect(mostly).
It spans far. That means open plans and giant windows, which is exactly what often sells a unique stay.
It is consistent and prefab friendly, so quality does not depend on which crew showed up that morning.
What you have to respect with steel:
It costs more, both in material and in labor.
It needs specialized crews. Connections mean welds or self-tapping screws, not a nail gun.
Thermal bridging. Steel conducts cold and heat straight through your wall, so you must add continuous exterior insulation and thermal breaks or you will fight condensation and energy loss forever.
It is hard to change on site. You do not improvise with steel.
A Few Other Factors
The material is only part of the decision. A few other things will push you one way or the other.
Weather
Your climate matters. High wind, heavy snow, hurricane and seismic zones all put extra demand on the frame, and that can change what your engineer signs off on.
Permitting
Your local building department has opinions. Some jurisdictions are very comfortable with steel, others are set up almost entirely around wood. Ask before you design, not after.
Insurance
Framing material can affect what you pay and what you can even get covered. Steel is non-combustible, and in fire-prone areas that can work in your favor with a carrier.
Ask these questions early. They are cheap to answer on paper and expensive to discover on site.
That's all for today.
Till next week, dear readers.
