In 2016, we had the incredible opportunity to evaluate the load-bearing capacity of our Treehouse Attachment Bolts (TABs) at the ICC-accredited testing facility at Washington State University (WSU). There, we conducted a series of directional tests on our Standard Limb (SL) and Heavy Limb (HL) TABs in two different tree species: Doug Fir and Western Red Cedar. Made of heavy-duty, heat-treated steel, TABs are the backbone of our science of treehouse-building – we use them in every one of our builds around the world. The results blew us away, demonstrating that our TABs exceed expectations for how much force they can safely endure. WSU’s findings underline the strength of our treehouse hardware and will benefit the treehouse-building community for years to come, helping us build the safest, most sustainable treehouses possible.