Addition vs. Buy with sq footage

Got a question guys:

Is it better, given the current peninsula prices of $1K/sq ft to buy the square footage already there or to add on?

What’s the current price rate for doing an addition? Let’s say 1000 sq ft and needing a bathroom, but not a kitchen? Like you take a 2-1 and expand backwards adding either one or two stories and putting in a family room (on the bottom), plus two bedrooms and a bathroom (second floor). Redwood City, Inc flats or Unincorp part of RWC, flat part.

How does an addition change the property taxes? How is that amount assessed?

How long does an addition take?

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Elt1 or ptiemann are better here.

But my 2 cents, To my knowledge, additions are cheaper at $200/sqft to $350/sqft (higher finish material) for single story even now. Labor is tough to get, people won’t come for small jobs. It all depends how do you work it out.

The trouble is current layout and how much you can extend without affecting the beauty. Second issue is lot size, shape, slope and county/city rules, esp set back limit and max size limit. You need to have an architect eye/view on those homes

To my knowledge, if additions does not exceed beyond 50% size of current home, it is considered add-on and property tax likely be cheaper. Otherwise, city/county revise as if new home built. This varies city to city, check your city planning departments.

Again, I am not an expert/experienced, gathered from my friends experience (Cupertino, Sunnyvale, San Jose).

RWC, elt1 is best to for you.

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The only deal at RWC i see is this (but backed up by some creek/stream)

Other one is

Just from remodeling a unit in the building that I sold, material/supply cost has gone up a lot lately. My contractor was complaining about how much plywood per piece was at HD now…

yes. But others are pending that could’ve worked…

Santa Clara tough to add one more bath as we have detached garage, but that can be converted I hope with a bath like 4 / 2.

Ruby st is backed up with a creek, potential flood damage, may be FEMA insurance etc.

I need 1800 sq ft and a 4th bedroom.

(Sorry I think I misread your post)

Santa Clara tough to add one more bath as we have detached garage, but that can be converted I hope with a bath like 4 / 2.

If home is 1030 then garage is 440 sqft, almost 1470 sqft

The detached garage is problematic if it can’t be brought to the side of the house, but 4800 sq ft is on the smaller side. Most lots are 6200.

That said, I agree that this kind of house is what I’m looking at.

I agree 4800 sqft is small, but higher area comes with higher cost too. RWC has become crazy nowadays and I do not know where it will end !

You know the truth, first to get in a home, then it appreciates, you sell and move bigger area.

This is what I have been telling to my friend/waiter (for 20 years) to get a some Condo/Townhome in bay area, but he is firm on SFH.

Yeah. It really is crazy…

I’m wondering why this one isn’t pending yet, though:

So still wondering though–what is the sq ft cost to build? A couple of years ago, elt1 said $400. Wondering if that’s $500 or $600 now.

$1k/sq ft is misleading. Most of what you’re buying is the land value. That’s why the existing house costs so much. It’s rare I’ve seen additions that work well in terms of flow and function of the home. Most seem like something extra bolted on.

You’ll notice for the same size lot the price per sq ft usually decreases as the home size increases.


Could be, contractors in the BA can charge whatever they want. Talk to a few. I have few connections left. But I heard prices are outrageous. Buy then add on in the next recession…
I would avoid a major addition. Maybe take a 3/2 and turn into a 4/3. Add a 600sf mater suite at ground level.
$500/SF . $300k


True. But minimum I’m seeing is $700/sq ft, so if cost to build is less, then the overall price tag could still be better.

I’m definitely looking at all angles.

elt1, what is the cost of building this home, now in 2018, for an experienced builder (tear down and rebuild like this)? Will it cost 800k or 1M or 1.2M level?

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I don’t really know anymore. Been living in paradise too long. Besides all my contacts are retired like me. My generation had a lot of great craftsman. There is now a shortage of skilled labor. Costs are skyrocketing and quality is suspect. There is even a shortage of unskilled labor… nowhere in the BA to house cheap labor. I would go to Stockton or Sacramento to get reasonable bids. My Stockton dentist will do a crown for $800 that would cost $1600 in San Carlos.


Cool, housing market dissected by dental procedure costs…


Labor is the most expensive part of construction


Good advice from Elt1. Build only what you just need and defer the rest for the next recession. I was able to build 500 sqft addition(includes a bathroom), and refloor old house, new roof everywhere, redo 2 bathrooms, reframe a garage, new windows, new stucco/exterior paint, 800 sq feet of paver pathways, architect + city fees - all inclusive about 290$ a sq ft. My interior finishes are nothing outstanding. Just simple stuff.