Johnston Contracting Services Tiny Homes & Cottages Logo


500 Metcalf St., H1
Sedro-Woolley, WA 98284



Johnston Contracting Services uses 2D and 3D software to engineer and design pre-fabricated structures. This allows open lines of communication with the client through virtual walk throughs and realistic models. Designs can be used for a permitting process, contractor installation and for bidding.

JCS specializes in prefabrication of commercial and residential structures. The in house design team “Builds Green” through efficient design, and fabrication in a controlled environment. A controlled environment helps manage waste and moisture content.

Prefabrication is a building technique that refers to fabrication of parts for a structure, or product at a different location and transported to a site and assembled to form a completed structure.

With the thought process done in the design phase, a structure can be assembled on site in roughly 1/3 the time of a traditionally built structure. JCS refers to prefab in relation to roof, floor, and walls for custom structures like homes, buildings and even small outbuildings or accessory dwelling units (ADU’s).


Permit plan sets


Plan set drawings are a combination of design drawings, and structural drawings.  In larger projects and jurisdictions, electrical, plumbing, and landscape plans may also be required.

JCS has the ability to produce full sets of design drawings and have them engineered in multiple states.  A "Ready for Permit," package will include all necessary items to submit your project to the building department, and incorporation of all design changes required by the building department.  Let JCS help guide you through the permitting process.