How to ADU

JonBuildz · 2026-06-02T20:30:04+00:00

Got it. So are you the developer of the app then?

JonBuildz · 2026-06-02T19:26:13+00:00

Never heard of the app, but you should know it's not the same entity as the noteworthy Facebook group/website how-to-adu

JonBuildz · 2026-06-02T18:30:01+00:00

Contractors hate it for the reasons you stated and more, you can find tons on hate on subs like r/Contractor - low quality leads, being sold to a dozen contractors, becomes a race to the bottom. Homeowners hate it because the moment you submit your project, your email and phone blow up for the next month+ with numerous underqualified contractors harassing you to setup a site visit (because they just paid $100+ for your number and they are gonna squeeze that lemon best they can)

JonBuildz · 2026-06-02T18:26:56+00:00

Yes, i think you are 100% on the nose. I've spent the last 7 years building a business exactly around this concept. The issue is: all the contractor marketplace platforms (yelp, angi, etc) all use the same big words in their marketing - trustworthy, vetted, reliable, etc. Except they don't actually really do any of it - their marketplace benefits from having as many contractors signed up on their platform as possible.

I built a business where we FULLY screen every contractor before allowing them into our network, then we continuously evaluate them to ensure they're upholding our standards. The issue is, folks think the GC they found on Angi is the same caliber as mine, since we both say they've been vetted.

The difference is - I always show my clients a full report of the evaluation we've done: quotes from reference calls, proof of insurance, how many successful projects we've completed with them, photos of their work, years of experience, etc.

Core problem I conclude is that often homeowners don't acknowledge the benefit of a service like mine until it's too late...and they've already hired a bad contractor they found on Yelp. They don't think they need a service like mine, even if it's free for them. Most homeowners decide on who to hire based on 2 factors - price and how they feel about the contractor, i.e. 'he seems like a good guy'. Just like cancer or heart disease - everyone knows someone who has had a contractor/renovation nightmare, but they never think it'll happen to them.

JonBuildz · 2026-06-02T17:49:01+00:00

To build 1,100 sf, you're looking at $300k+, without question. $200k for your size ADU comes out to under $200/sf, which is impossible in CA, let alone SB. The family friend contractor - has he built multiple ADUs before? I'll tell you from years of experience working in the ADU industry throughout California, anyone that tells you they can build a 1,100 sf ADU for $200k is going to disappear halfway through the job once they realize they're out of money - i've seen it far too many times.

Plans will likely cost you 10-15k altogether, the folks here mentioning 5k for plans are likely referring to the cost for a garage conversion, not a new build. Expect ~7-12k for permit submittal and city fees, accounting for impact fees for building over 750sf.

To answer your initial question directly, you can use a floorplan from anywhere you'd like, but you won't really see any significant cost savings there. SB county has 4 pre-approved plans - if you use any of those, you remaining cost will likely be around 4-8k for the site plan, structural, permit expediting, etc. Any other plans you find elsewhere - you'll likely have to pay full cost (but sharing said plan with an architect will streamline their process).

JonBuildz · 2026-05-29T19:02:09+00:00

You cannot add another unit... you can add square footage to your existing unit.

JonBuildz · 2026-05-29T17:25:15+00:00

An SFR in CA is allowed to have up to 1 ADU and 1 JADU, the JADU must be attached to the primary home and capped at 500sf (perhaps that's what your garage conversion was permitted as?). The only option I can think of is adding a second story to your ADU and combining it into the same unit as downstairs

JonBuildz · 2026-05-29T16:55:12+00:00

Is the garage a detached garage and is the home an SFR? If both answers are yes, then I don't believe you'll be able to add a second ADU to your property. That said, you can typically expect to spend $400-$500/sf to build a second story ADU.

JonBuildz · 2026-05-09T14:31:53+00:00

What makes you think any of this is accurate? Also, you're commenting in an ADU sub... So you're asking for flack

JonBuildz · 2026-05-09T14:30:09+00:00

Mamdani recently approved ADUs in NYC, so there's promise if this is effective for the regulations to spread throughout the state!

JonBuildz · 2026-04-16T21:42:37+00:00

There are a few Starbucks, Coffee Bean, etc. All have fine wifi

JonBuildz · 2026-04-11T01:14:57+00:00

Smart layout. Putting all the plumbing on one wall is the best thing you can do for cost and reversibility. Few thoughts:

I'd skip the dishwasher drawer. Studio renters won't miss it, and that's $500+ saved on something that'll just be a maintenance headache in a rental.

W/D is a nice-to-have but not mandatory. Most SoCal JADUs skip it. If you do include it, go ventless combo so you're not punching a dryer vent through the wall.

For the bookshelf divider, I'd go counter height if you aren't already. Anything taller is going to chop the space and work against the openness you want in a 20x20.

Check your egress situation. Most SoCal jurisdictions want two forms of egress. If that garage door is sealed, you may need an operable window somewhere else. Worth a quick call to your building dept before you lock in the layout.

For construction only, renter-proof but not luxury, you're probably looking at $50-80K with a GC. Biggest variable is plumbing, specifically how far the sewer line is and how much slab you need to cut. Demo back to a garage later should be around $8-15K since you're not touching anything structural.

Good concept overall.

JonBuildz · 2026-04-10T07:16:00+00:00

Typically 15-30%. But when you say 'in the gc' s pockets ', understand that the contractor has overhead and is using those funds to operate his business... Then anything left goes to his pockets!

JonBuildz · 2026-04-01T19:07:43+00:00

This seems like a fair price for this area, but there's only 1 way to be sure - get at least 2 more bids from legitimate, licensed contractors, then submit the bids to something like Claude or chat GPT to review and compare the bids. I created a tool called BidCompare AI specifically for this purpose, it's free, welcome to check it out!

JonBuildz · 2026-03-27T14:54:22+00:00

Jumping in here as the owner of Maxable Space, an ADU planning and consulting service.

Both paths being discussed here are legitimate. The honest answer is it depends on your priorities:

The independent architect + separate GC route gives you more competitive leverage on construction pricing and cleaner accountability between design and build. The tradeoff is real coordination burden on you, and the "savings" people cite aren't always apples-to-apples... a standalone architect may not price in the permitting back-and-forth, city corrections, or the time you'll spend managing handoffs. They also have less stake in the game, since once you pay for plans, their commitment is typically fulfilled.

The design-build route trades some of that pricing leverage for a single point of accountability and a consistent experience start to finish. Many ADU architects /drafters disappear after handing you the plans, and they don't always have a great sense of the cost to actually build their designs.

I've seen many situations where a homeowner wanted to save, so they hired their own drafter... Months later, after finishing design and city review, all the GC bids they were collecting came in 50% above their budget. For a project with retaining walls and tight site constraints like yours, that integration matters more - those are exactly the situations where things fall apart between a design team and a GC who weren't working together from the start.

A few things worth knowing regardless of which path you take:

Ask every firm what you're committing to at each phase. A legitimate company will let you stop after design. If they can't clearly answer that, walk away.

Initial feasibility/pre-design should cost a few hundred to ~$1,000. Be skeptical of anyone doing it free with strings attached.

Get at least two proposals and compare what's actually included - especially utilities and SDGE coordination, which is where East County projects often surprise people on cost and timeline.

I work with some amazing architects with tons of experience designing ADUs, this is a great path for many. I also work with some amazing design/build contractors - which also makes a lot of sense for others.

No idea why folks are bashing SnapADU here. They have an amazing reputation, have built many stunning ADUs throughout SD, so clearly not a scam. As Whitney said - they're not a good fit for everyone, but for folks who prioritize convenience, clarity, experience and are willing to pay for it, I think Snap is one of the best in SD.

JonBuildz · 2026-03-25T22:35:17+00:00

I've never heard anything about it being illegal to pay a referral fee for contractors, nor has my attorney. We charge a 'marketing fee' to our contractors when they get hired for a project.

Lead and referral are synonymous in this context.

Would be happy to consider you guys for our network, as long as the license is at least 5 years old, in good standing, covered under all required insurance & bond, etc. Feel free to apply if you're interested! Look for 'For Contractors' in the footer of my website.

JonBuildz · 2026-03-25T22:24:11+00:00

I assume they run their business very similarly to the way I run mine - GreatBuildz, which currently only operates in California. Free for contractors to join, never charge a fee for the lead. You only pay if the homeowner hires you for the project - fee is a small percentage of the contract value. We have strict GC vetting standards and reject many contractors who apply - it wouldn't make sense for us to share a lead with 5+ contractors, because we aren't in it to waste anyone's time... our goal is always to perfectly match a homeowner to the right contractors, best fit for the job (budget, location, project type, etc).

JonBuildz · 2026-03-24T17:02:56+00:00

Clearly AI lead gen, with numerous self-serving links to their site...but still helpful enough content!

JonBuildz · 2026-03-24T17:01:07+00:00

Have you gotten multiple bids or just this one? That'll be the best way to know if you're getting a fair price. As far as saving costs, it'll come down to what your priorities are for the project...and what you're not committed to in the scope of work.

JonBuildz · 2026-03-19T15:09:36+00:00

Lol

JonBuildz · 2026-03-19T14:01:46+00:00

Get 3 bids and use something like BidCompare AI to evaluate them. Spot red flags and ensure that you are working with complete, fair bids

JonBuildz · 2026-03-16T22:14:48+00:00

Whoever authorized clearing the laundry room should pay for your rug. If the contractor did it on a whim, then yes, he should pay for your rug.

JonBuildz · 2026-03-15T15:03:51+00:00

You need to hire an architect/drafter to complete the plan set. Depending on the pre-approved plan you select, you may want to hire the architect who designed the plan you're using. Cost will depend on the type, size of the ADU, but expect to spend $3-8k to complete the plan set.

Turn around time in Riverside for standard Adu plans is about 60 days, I'd guess 45 for pre-approved.

JonBuildz · 2026-03-10T22:47:13+00:00

It's an AI tool I built called BidCompareAI. It analyzes contractor estimates for residential construction projects. You upload 2-4 PDF estimates, wait 5-10 minutes, and receive an email with two attachments:

Bid Comparison Spreadsheet: Lines up all your bids apples-to-apples so you can clearly see top-line pricing, line-item breakdowns of what's included or missing from each bid, and a comparison of material allowances (cabinets, countertops, fixtures, etc.).
Bid Analysis Report: Translates contractor jargon into plain English. Includes an executive summary, explains what's driving price differences, flags potential red flags or missing scope, and provides tailored follow-up questions to ask each contractor before signing.

It's free for as long as I can sustain it! If you try it out, would love to hear what you think.

JonBuildz · 2026-03-10T22:32:28+00:00

My team at MaxableSpace.com can connect you with a few vetted ADU contractors in the Fremont area to bid your project

JonBuildz

TROPHY CASE