Detached ohana units
A small home of its own, behind or beside the main house
A detached unit has its own foundation, roof, entry and utility connections. It is the most private of the five, and it has the longest list of questions: how large, how far from the line, how steep, and how the water and sewer reach it.
Not included unless the scope says so: appliances, furniture, fencing and landscaping beyond the work area.
What a detached unit includes
Foundation and framing designed for wind and termites
Roofing, windows, doors and exterior finish
A kitchenette, a bath and one or two bedrooms
Water, sewer or wastewater, and electric connections
Site work, a path to the door and the final inspection
What changes the cost
Six things move the price
The same floor plan costs different amounts on different lots. These are the reasons.
The slope
A steep or narrow lot changes the foundation, and decides whether a truck or crane can reach the back.
The distance to utilities
Trenching from the street or the main house to the new unit adds time and material.
Sewer or wastewater
A lot on the city sewer connects one way. A lot on a cesspool or septic system may need a new wastewater system.
Size and kitchen
A second bedroom or a full kitchen costs more than a studio with a cooktop.
Wind and termites
Hurricane ties, treated framing and salt-resistant fasteners are part of the plan, not extras.
What ships
Windows, cabinets and trusses carry long lead times, and their price is the price on the day they are ordered.
We print no figures here. The written estimate lists each of these for your lot.
How it goes
A sample build, start to finish
Counted from the day the permit issues. The permit itself is on the permit path page.
- 01Weeks 1 to 2
Step 1: Site prep and layout
Clearing, staking, trench lines and the first inspection of the layout.
- 02Weeks 2 to 5
Step 2: Foundation
Footings and slab or posts, with the inspector's visit before the pour.
- 03Weeks 5 to 10
Step 3: Framing and roof
Walls, trusses and roof deck go up. The weather-tight shell comes next.
- 04Weeks 10 to 16
Step 4: Windows, rough work and inspections
Windows set, then electric, plumbing and mechanical roughed in and inspected.
- 05Weeks 16 to 24
Step 5: Finish and final
Drywall, cabinets, flooring, paint and fixtures, then the final inspection and the walk-through with you.
Sample content.
Permits and rules
What the city and the lot decide
We check these against your parcel before you pay for drawings. The owner confirms them with the Department of Planning and Permitting.
Size, height and setbacks
How large the unit may be and how close it may sit to the property line depend on your zoning district and the rules now in force.
Parking and access
Some lots must keep or add parking, and the fire department needs a way to reach the unit.
Utilities and capacity
A water meter or lateral, a sewer connection and electric service each need a sign-off.
Questions
Questions about detached units
Can I build more than one second unit?
Rules on how many dwelling units a lot may hold depend on the zoning district and the rules now in force. We check your parcel and tell you in writing.
Does it need its own water meter?
Sometimes. It depends on the lot, the size of the unit and what the water board requires. We ask the water board early because it runs beside the plan review, not after it.
Who lives in it?
Whoever you plan for. We draw the unit around the person: a step-free path and a roomy bath for a parent, a quiet desk for a grown child. Rules on renting it are a separate question.
How long does it take to build?
The sample above shows the build after the permit. The permit review is the longer and less certain part, so we give it a range on the permit path page.
Does your lot have room?
Send a photo of the yard and the driveway. We'll tell you what to ask the city before you pay for drawings.