An accessory dwelling unit is a small building with all the systems of a large one. That is what makes it a different job from a room addition — the framing is simple, but the unit needs its own everything, and where those things land is decided long before anyone cuts a stud.
Utilities come first. The unit needs water, drainage, and power, and how far those runs have to travel from the main house shapes both the cost and the site layout. Sorting the trench routes early usually costs less than moving them around a foundation that is already poured.
Then siting. Detached or attached changes the build substantially: an attached unit ties into the existing structure and has to respect its load paths, while a detached one is a standalone building with its own foundation and its own setbacks to respect. Which one suits a lot is usually decided by the lot, not by preference.
Rules on setbacks, height, parking and unit size vary between cities and counties, and Fox Framing works across four of them. Check with the building department for the jurisdiction the lot is actually in before you fix a footprint — the answer genuinely differs between, say, San Bernardino and Irvine, and it is not something to take from a blog post.
We build ADUs from slab to finish, detached and attached. Call (909) 758-1355 and we will walk the lot with you.
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Let Fox Framing Inc handle the structure — call and tell us what you are building.