Need help - Estimated Cost of Remodel/Addition


I have been Suggested to have this money ready for the remodel of primary home.

I know we have balpark figure of $350/sqft, but this home has normal ceiling, but not high ceiling.

New Addition and Remodel:

874 Square Feet Remodel + 1,900 Square Feet New Addition x $175-$250 per square foot.

2,774 Square Feet Total x $175 = $ 485,450 Low End

2,774 Square Feet Total x $250= $ 693,500 High End

Includes home fire sprinkler.

Doesn’t Include Covered Front Porch, Patio, Landscape Plants,Cameras, Security, Intercom, lawn sprinkler system, Landscape Features such as walls, gates, planters or fencing, paving or driveway which you need to add about another $100,000.

These are items that you would discuss and work with your general contractor.

  • I have carrying cost for 12 months.

Is this normal range at San Jose price or something I am missing?


Just financing and soft costs like design, permits …Demo, utilities dump fees …


rewiring (100 amp min, 200 amp with electrical charger), upgrade existing plumbing, waterless tanker heater, kitchen appliances…


Yes, soft costs like design, permits are additional.

Demo and dumping should be part of above costs.

I have already installed 200 amp panel with city permit and one electrical charger. Costs $5500 incurred already.

Definitely, rewiring needs to look at and the cost ( I think that I need to account).

The above plan includes centralized A/C and heater in the design. Rest, need to check.

Our architect told us get a pre-quote from vendors, before we start applying permit to know how much it costs appx. Depending on the costs, we need to reduce the scope before applying permit.


Use subs from 209 or 831 area codes


GC profit
GC contingency
GC administration


This I do not understand.

My plan is to contact few builders and ask for quote/contract. They need to have GC and the team to finish the job. The builder must have GC to complete the task or align the resources etc.

The plan is pay the builder on milestone basis.

Am I missing something here?


Planning to contact builders from down south ( Morgan Hill, Gilroy…) as they have lot of subs.


You may see these costs listed individually as line items depending on the type of GC you use. Whether or not you see it doesn’t change the fact that you need to pay for it. If you aren’t paying for it with dollars and cents, you are paying for it in other ways.

IMO, the low end looks pretty low. If you are doing this for the first time, don’t count on that to get things done. Mistakes will be made, and they will need to be remedied.


First time posting here. At 250/ sq ft i think this is a steal. When you got an estimate, did the builder include take offs from all material suppliers? If not, take a close look at it and check if it is realistic. Builders in the Bay Area typically charge 20-25% for O+H(Overhead & Profit). Is that included in the $250/sq ft You might also want to keep a 15% contingency fund on top of everything else. You will end up using every single penny from this fund.

Did the builder give a “rough estimate” or a contractual agreement to sign? If it is the prior, then that is just that “rough estimate” and he can leverage his position to his benefit after you get into contract with him. For a $700,000 estimate i would get a performance bond signed and have the contract reviewed by an experienced real estate lawyer. Performance bonds typically cost 1% of the project cost.I highly recommend it!


We are still in design stage, not at the pre-quote level yet. My arch is, in fact, telling me that my desired plan needs this much cash and she is checking with me whether it is fine to proceed further?

This is an estimate, based on my requested design, from my architect, from her client’s previous quotes. Her quotes were ranging $175/sqft to $325/sqft and client choose $250/sqft bidder.

My architect was telling me that I need to have pre-quote from selective builders, review it before submitting to city approval.


$175 or $250 is next to impossible over here and I speak from experience being a GC licensed in state of Ca and having flipped over 15 properties and built over 10+ scrapers now you’ll go into tug of war with people who would be actually working for you. This stress is not worth the few pennies saved.


Jil, are you working with a design build firm that are giving you with these estimates or did you hire an architect yourself?

Using square foot as a measurement of potential cost is an exercise in frustration filled with errors and pitfalls. Contact a local GC with a full set of approved developed plans and let him come and take a look at your project. Have him take a look at it thoroughly and come up with a contract price.

I agree with cloud, the $250 is almost impossible. For your sized project, materials alone would cost $100/sq ft in the Bay Area. If you need fire sprinklers the local fire department jurisdiction may instruct to install an oversized water meter which costs a fortune to meet the GPM requirements. This is just an example, but there might be several hidden costs that you or your architect will not catch but an experienced GC might.


FYI: I am working with Architect and still need to engage GCs with full plan. Before going to the full plan mode, Architect gave a ballpark estimate. She has already indicated me to be ready for $325-$400 depending on finish Materials.

I fully agree with both of you (and others suggestion). General guidance here, from many members, is to assume around $350/sqft.

Now, as such, I am forced to reduce the size of the home addition (from 1900 to 1400) to meet my finances.