The Treehouse is Computational Linguistics Laboratory in the Department of Linguistics at the University of Washington. DELPH-IN related work at the Treehouse includes development of the LinGO Grammar Matrix and the the Montage project.

The LinGO Grammar Matrix, developed in collaboration with DelphinLingo and DelphinOslo, is a starter-kit for the rapid prototyping of scaleable precision grammars. Initial development of the Matrix was based on the LinGO English Resource Grammar and the JACY Japanese grammar. Early versions of the Matrix were used in the development of the NorSource and Modern Greek grammars, and feedback from these projects has spurred various refinements. More recently, development has also been driven by the application of the Matix to a variety of languages in the multilingual grammar engineering course at UW. Matrix-based grammars are all compatible with the LKB and all map surface strings to MRS representations.

The Montage project, involving UW, Stanford, and MPI Leipzig, aims to leverage recent advances in grammar engineering methodology and technology to assist field linguists in the documentation of underdescribed languages. The project pairs Matrix development with coordinated work on tools to assist linguists with ontologically-linked grammatical annotation of collected texts and the production of linguistic resources in best-practice digital archival format. In addition to benefitting from the DELPH-IN collaboration, Montage also has links to the computer-assisted linguistics and language archive communities, including E-MELD, OLAC, and the Rosetta Project.