Lic #1007864 · Santa Clara County · General Contracting
Custom ADU & Additions
Detached ADUs, room additions, garage conversions, and JADUs — permitted, engineered, and built to estate standards.
Acre-plus hillside estates with demanding engineering — retaining structures, long driveways, and architect-driven custom construction.
California's ADU laws have unlocked enormous property value, and JMG builds accessory dwelling units and home additions that match the main residence — not prefab afterthoughts. From Los Altos to San Ramon, our ADUs and additions command premium rents and appraisals.
In Los Altos Hills and across Santa Clara County, JMG delivers adus & additions under California Contractor's License #1007864 — permitted, inspected, and personally overseen by owner Jerry Guinn. We manage the entire lifecycle: feasibility, design, permitting, utilities, and construction, delivering turnkey units and seamless additions ready for family or income.
Los Altos Hills keeps its rural character by rule: one-acre minimum lots, private lanes, the town pathway system, and properties that may run on septic rather than sewer. Projects here demand site-sensitive engineering and careful utility planning — exactly the ground-up estate work JMG self-performs with in-house crews.
What's included in Los Altos Hills
Recent adus & additions work
The process in Los Altos Hills
Private Consultation
Walk the property with owner Jerry Guinn. Honest scope, realistic timeline, and a written line-item estimate — free.
Design & 3D Rendering
See the finished project in photorealistic 3D before a single wall comes down. Finishes get locked before demo day.
Permits, Handled
Plans, submittals, corrections, and city or county coordination under CA License #1007864. You sign — we run the process.
Build & Final Inspection
Sixteen in-house trades on one schedule, one accountable owner. Inspection passed, walkthrough done, keys in hand.
ADUs & Additions in Los Altos Hills — FAQ
Feasibility check on your lot, design and 3D rendering, permit submittal, then construction. State law guarantees most ADUs a 60-day ministerial review — we prepare complete packages so that clock never stops.
Related reading
More services in Los Altos Hills
ADUs & Additions in other cities
ADUs & Additions · Los Altos Hills