It used to be good old fashioned wood stick framing was the only option for constructing a tiny house. These days, options are plentiful and still growing! Here are the options we offer along with our take on the pros and cons of each.
Advanced Wood Framing-This is our modern twist on a classic, reliable system-wood stick framing. Most tiny houses being built today still utilize the familiar system of 2×4 wall studs and 2×6 rafters. In an effort to reduce weight, reduce redundancy, and increase thermal performance, we utilize a method known as Advanced Framing. Stud and rafter spacing is set at 24″ centers. Since rafters sit directly above studs, there is no need for a double top plate, just a single. Instead of placing a lot of trimmer studs at doors and windows, we use Simpson metal angles that safely transfer shear forces to the king stud. We attempt to size and place windows in between stud spacing so that we don’t have to add any more studs than is needed. This doesn’t always work with the layout, but when it does it sure makes life easier. Wood framing is economical, familiar, forgiving, and extremely versatile. We can do curved and warped surfaces with wood that are not possible with other methods. The downside? It is a tad bit lighter than SIP framing, but heavier than steel framing.
Light Gauge Steel Framing– This method takes the familiarity of wood framing, but uses steel studs. All of the studs are screwed together, not nailed. Instead of using solid heavy headers over large rough openings, a lightweight metal truss is integrated into the framing. The framing system itself is amongst the lightest, but it presents challenges when it comes to attaching other materials to the studs. Exterior sheathing isn’t too big a deal with self tapping screws, but what about interior materials? We would have to use a paneling product that can also be attached with self tapping screws. Let’s say you use 3/8 or 1/2 drywall. These negate the use of lighter framing altogether. You could use 1/4″ plywood, but screw holes will have to be filled and the panel painted. What if you want a stain grade natural wood product? You would then have to use a thick tongue and groove board and blind screw into the studs, again negating the weight savings. Trailer Made is working on sourcing pneumatic spiral fasteners for their steel framing system, which is a move in the right direction, but these nails are still much clunkier than an 18 ga finish nail, so you either have to be ok seeing large nail heads, or be ready to wood putty every single hole. You would also have to purchase a specialty nail gun to shoot these nails. You could also add a wood furring strip to the inside of the metal stud so you have something to nail a product like 5/16″ pine v-edge boards too, but now you are adding weight back into the build in addition to losing interior clear width. If you really want steel framing, we can do it, but expect higher pricing and not much weight savings in the overall build. We would subcontract the fabrication of the steel framing over to Trailer Made Trailers, who now in addition to producing the highest quality tiny house trailers on the market, is now entering this market of steel framing kits for tiny houses, along with Volstrukt.
Structural Insulated Panels (SIP’s)– SIP’s are our personal favorite! Here is a whole write up about them! We do find them to be just a tad bit heavier than stick framing due to the fact that there is OSB skin on both sides of the panel, and there are still some studs at the panel edges and rough openings, but the panels are pre-cut, go up really fast, are very straight, have superior insulative qualities, are incredibly strong, and give you infinite attachment points for interior finishes, cabinets, and built ins. No need to worry about hitting a stud! While we cannot warp the panels, we can cut circles, arcs, and ovals out of them. If you want some form of a curved roof, having the CNC routers cut the curve in the wall panels and then stick framing the roof sure makes life easier for us! The downside to using SIPs are weight and freight. They will be heavier than steel or wood stick framing. It is not outrageous though (see solid timber log style below!!) The main obstacle to overcome is freight. The SIP plant we use is in Michigan and panels have to be shipped to our shop in Durango. To only ship one project is not cost effective. Two projects is better, but not quite cost competitive with stick framing. Three projects on one truck will reach the break even point with stick framing. Four or more and it is actually cheaper to use SIP’s vs stick framing. In terms of doing custom tiny house builds with SIP’s, we are the most experienced builder in the country.
Therma Steel Panels– This company is based in Virginia. Although a panel product, these are not technically considered SIP’s. They contain light gauge steel framing members encapsulated in EPS foam (same insulation as with traditional SIP’s) The studs are alternated and placed such that you still have attachment points for exterior and interior materials, but with no thermal bridging. This product is even lighter than steel framing, just as strong if not stronger, and has better thermal characteristics. I know of at least one other tiny house builder who has had great success using this system, but this is in part because they are a larger company and use this product almost exclusively, so they can get better freight rates with full trucks. As a smaller builder, we would not only have to pay a lot in freight, but the product itself is the most expensive framing system that we could use. Somewhere in the vicinity of 2-3 times that of traditional SIP’s. Still, if the lowest weight possible with superior insulation is a top priority, this is the best of the best.
Solid Heavy Timber Log Cabin– We’ve only done two builds in this style, and there is reason for this. First and foremost, this is the absolute heaviest framing method you could choose, and thermally not quite the best option, at least on paper. Locally, we can source solid timber in Spruce or Ponderosa Pine. The spruce is lighter but harder to come by. We will try to make sure the logs are as seasoned as possible, but they will probably still shrink in a few months, meaning you will have to come back in and chink them. Wood typically only rates at R-1 per inch, but despite this, the sheer massing seems to keep the house cozy one it is brought up to temperature. The ceiling would be stick framed and insulated normally. Other drawbacks include not being able to run wires in the logs, instead having to do exposed conduit. Same for plumbing lines. Why go log framing? The aesthetic would be the primary reason. You don’t see many log framed tiny houses. Another advantage is ease of construction. Instead of stick framing and working with all these different layers, these walls are only one layer and go up very quickly, saving on costs.
Light Log Cabin Style– If you like the “look” of a log cabin, but not the weight, then we can source kits from Unforgettable Tiny House. These kits utilize seasoned Siberian spruce for a great balance of weight, insulation, strength, durability, and aesthetics. This wood is much more stable and should not need chinking down the line.