Why HydroGap for your tiny home?

HydroGap keeps a tiny home dry and mold-free.

Seattle Tiny Homes’ lead contractor, Ben Klassen, is known for being cutting edge. While attending a recent national building convention (where he took first place among all the contractors in a final test for certification), Ben learned about HydroGap, a state-of-the-art house wrap. Because mold and moisture can cause significant problems in tiny spaces that are not built properly, Seattle Tiny Homes is vigilant to intelligently construct a problem-free product that will last a lifetime.

The benefit of HydroGap is that it has built in spacers, with a gap of 1 millimeter, for water to flow freely away from the house. The house wrap provides superior protection against mold and moisture damage. And it’s an ideal combination of strength, water-holdout, and vapor permeability.

Innnovative products like HydroGap, combined with old-fashioned, high-quality construction, ensure that every Seattle Tiny Home will provide a lifetime of comfortable use.

Make a house look like a home (and keep it stable)

For a truly homelike feel, there’s nothing like cedar siding on the exterior. For the Ballard model we’re building, we used kiln-dried, tight-knot cedar. We chose a lap pattern with a seven-inch reveal alternating with a one and three-quarter-inch reveal. We love the distinctive look it gives.

Here’s a close-up of one of the dormer windows. We used cedar sidewall shakes rather than continuing with the siding. Someone is going to enjoy his or her view out of the little red window!

A bay window also adds a homelike touch, but window manufacturers don’t build bay windows small enough for tiny homes! So we had one custom built. It’s installed at the back of the home and adds a sense of light and extra space.

Each corner of the tiny home is secured with a hurricane tie-down. For added safety, the stud securing the hurricane tie-down is affixed to five inch steel tubing on the trailer.

In addition to working on our tiny home, our building team has been busy with another tiny structure. We thought you’d enjoy a shot of their handiwork. Notice the classic gambrel roof that makes this little building really stand out.

Details that make a difference

So what’s this and why are we showing it? It’s an image of the tiny home’s electrical box (above), which is where electrical power enters the structure. It’s also the location for the breakers. We also wanted you to notice the metal drip edge and extra flashing just above the box. It’s details like this, duplicated over all the windows and door, that ensure that air and moisture stay in their places.

Here’s another detail you might appreciate on the Ballard model tiny home we are currently building. We’re putting beautiful kiln-dried, tight-knot cedar siding on it, and we insert a metal plate – like the one you see above in the photo – behind the planks at every seam. Why? It’s just one more step to keep water out so the happy owner of this home will never have to deal with mold or rot.

The exterior of the Ballard model tiny home we’re building will soon be done! Here’s a shot of the cedar framing we’re adding to all the doors and windows (above). You’ll also notice the double flashing system to keep water and moist air out of the home. The first line of defense is the metal drip edge that slightly overhangs the window or door. Then, in addition, we’re also using Tyvek flashing tape to seal the top of the metal drip edge – creating an additional line of defense.

Take a peek at a sleeping loft under construction

We’ve been really behind on blogging (the tiny house will be built before we catch up!), so we wanted to start featuring some photos to give you an idea of what’s going on. This is a picture of one of the two sleeping lofts in the Ballard model we are building. Notice how the dormer window gives it a real sense of spaciousness – and a view outside.

Let the Light In

A large window on this side means plenty of light in the tiny home.

Using Tyvek Drain wrap instead of a rain screen saves a half inch in the width of the house - meaning that much more space inside.

The high quality Tyvek system for window flashing helps ensure water and air stay in the right places.

Living in a tiny space is great, but you want to ensure plenty of light and a sense of airiness. That’s why we designed the Ballard model with an abundance of windows.

For the windows themselves, we chose solid wood frames with aluminum cladding on the exterior for longevity. When installing them, we used the Tyvek system for window flashing. It’s more expensive than simple window flashings but is one more step to ensure that moisture and air stay in the right places.

Inside the house, the natural wood frames are beautiful and add a sense of elegance. No matter where you are in the house, the view outside is always close by.

Of course, adding windows to a tiny home is a bit of an art. There are multiple goals to consider: a sense of architectural balance, ensuring there is enough light inside, and best use of the space inside. In an environment where every inch counts, it takes a lot of effort to get the windows placed for maximum beauty and effectiveness. But we think we’ve succeeded with the Ballard model!

Raising the roof!

Early stage construction of the roof. You can see the beginning outline of one of the dormers.

A close-up of one of the dormers. Every angle of the wood has to be cut exactly right.


The roofing structure is in place, seen in this view from the back of the home. The actual windows will be added later.

The roof with the WIP (water and ice paper) installed. It's now ready for the final roofing material!

In a tiny home, you want the maximum amount of living space within the exterior dimensions. That’s one of the reasons the roof our Ballard model – a space designed for a small family – includes two dormers.

These dormers add a significant amount of space and light to our two sleeping lofts without making the house taller or wider. Of course, dormers that rise from the roofline are time consuming and require a lot of carpentry skill. Every angle has to be cut exactly right. But dormers are well worth the extra time and effort.

We also framed the roof for two skylights (which will be installed later) to let in even more light and views of the sky.

Some technical details: to create the roof, we glued and screwed half-inch CDX plywood to the rafters, then covered it with WIP (water and ice paper). The rafters themselves are secured to the top plate of the walls with TimberLoks®, which meet code requirements for hurricane tie-downs.


“Glue and Screw” Makes the Walls Go Up

The wall begins to take shape. The studs are secured to the trailer with TimberLoks®, a corrosion-resistant bolt that tightly ties the walls in place.

Each wall panel is glued into place, then screwed. This creates sheer panels for extra safety and also keeps squeaks and rattles to a minimum.

Progress! With the walls up, work has already started on the roof. Openings for the windows will be cut out later.

Construction is rapidly progressing on the Ballard model (a space designed for a small family) that we’re currently building. We’re a little behind on blogging, but here are a few details about the walls:

  • We designed the trailer so the majority of wall studs would rest on top of angle iron (extremely strong), then be secured to the trailer with corrosion-resistant TimberLoks®. Each corner of the walls is also secured to the trailer with hurricane ties.
  • Our team took care to glue and screw all structural components. This is extremely time consuming – taking more than five times longer than simply nailing – but it turns the walls into sheer panels that are super strong and able to stand up to high winds on the highway and any bumps or jostles from the road when the home is towed. We don’t want any squeaks or rattles!
  • We’ve chosen products with the greatest strength yet lightest weight, while trying to be as green as possible.

Our goal is to create a home in which the structure is fully integrated with the trailer. The measures we’ve taken exceed the international standard of building for hurricanes, but we want to create the safest environment possible for a family.

Labor Day celebration – construction has begun!

The floor framework inset into the trailer. The black material is a moisture/rodent barrier.

The insulation has to fit perfectly!

Zero ozone depletion potential - the way we like it.

The floor with the insulation installed. Now ready for the subfloor!

Building a tiny house is very different from building a regular home. Almost nothing is “standard.” It’s like creating a piece of art. It’s enjoyable, fun, but also takes a lot of time and skill to make sure the home is structurally sound. We’re thankful for our highly qualified team!

Just recently construction began on our Ballard model, and we’d like to share some details about the floor:

  • The base of the floor is hand-selected marine grade plywood.
  • We used a special vapor wrap barrier for the floor that breathes one way and is extremely resistant against condensation and rodents. Keeping moisture out is a top priority.
  • Because of the way the trailer was designed, we were able to set the floor down into the frame, adding even more stability to the house than if we had built it on top of the trailer.
  • Each piece of the floor was cut to minimize air gaps. Then the smallest cracks were filled with spray-in foam insulation. Using the latest insulation from Dow (zero ozone depletion rating), we were able to get an R-value in the floor of almost R20 (counting the flooring materials). No cold feed in this house!

We’ll keep you posted as construction continues. Happy Labor Day, everyone!

The trailer: a sturdy foundation

The foundation for our Ballard model home.

Just recently we took delivery of a trailer that will be the foundation for the Ballard model home we are currently constructing. Our team custom designed this trailer with several important traits:

  • It’s rated to hold up to 10,000 pounds.
  • The angle iron braces extending out from the trailer can hold nearly 1,000 pounds each. The studs of the home will rest on these extensions.
  • The angle iron cross members are specifically placed to fall directly under the floor joists.

Each element of the trailer is precisely planned to provide a solid foundation for our tiny home. The next step was seting up the trailer to be perfectly level to build upon, not even off by a few degrees. Construction can begin!

Not just any old trailer.

We’re getting ready to launch construction of a Ballard model home, and the first big step is selecting the right trailer.

After all, the trailer is the “foundation” for a tiny house on wheels. Pick the wrong trailer and you risk the long-term structural integrity of your home.

To get it right, Sharon (founder of Seattle Tiny Homes) teamed up with a structural engineer and two contractors to brainstorm the best solution. Together they designed a trailer with several goals in mind:

1 – Use every possible inch of the trailer to allow for maximum square footage while still providing complete support for the structure.

2 – Integrate the trailer fully into the home’s construction, so the home plus the trailer become one complete unit, rather than a structure tacked on to a trailer.

3 – Use the best quality materials to provide a lifetime of service, while still keeping the trailer as light as possible.

After multiple conversations and scribbled drawings, we’ve come up with an excellent solution. It’s a custom designed trailer with steel brackets that allow key studs of the home to be firmly secured to the trailer with TimberLocks®. We’ll also use Simpson strong ties at each corner. These and other extra steps make the tiny home and the trailer a completely integrated unit.

The end result is a home built for a lifetime of safety, stability, and longevity. In a strong headwind while driving, hurricane force winds, or an earthquake – this home should stand straight and true. In fact, it exceeds international hurricane standards.

We’ve ordered the trailer and expect it soon. We’ll post pictures when it arrives!