We’ve been researching costs to build an addition to our house here in Honolulu. Your site doesn’t list Hawaii, so I thought I’d contact you.

In discussing with architects and draftsman, we’re getting widely ranging estimates of $100- $350 per sq foot for an add on of a free standing 1000 sq foot residence over our current lanai. Any input is appreciated or info on how to get an accurate estimate.
Mahalo!
Don

Aloha Don,
(Note to readers: I had to look up Mahalo It is an Hawaiian word meaning thanks, gratitude, admiration, praise, esteem, regards, and respects)

Unfortunately, you did not give me any of the particulars of your planed addition that affect (greatly) the cost of building a home addition.

Photo of a Lanai courtesy of LA Times Crossword Corner

So, I ran the cost to build calculator found on my “Getting Started” page for building a simple 1,000 sq ft addition in the city of Honolulu.
I used the “Quality Class” # 6, building to minimum code (cheapest), all the way through (No HVAC, only a wall unit A/C), and came up with a total cost of $93,283 using a room addition contractor (General Contractor). That obviously, comes out to $93.28 per sq foot.

You could easily triple that cost depending on the quality of materials and design you choose.

As I have stated in previous posts, the cost per sq ft for small structures (home additions) is almost always higher than for larger structures, because subcontractors may want a few more dollars for their labor because they could be earning more on a larger job for almost the same amount of time, and because expensive costs such as roofs, foundations, etc. are being spread over a smaller sq footage.

Anyway, it’s interesting that I came up with a number close to your lowest bid.

As they say, you’ve only got one way to go, up!

Aloha, (I found out Aloha can also mean “Goodbye”),
Carl

(Aloha Mr. Heldmann,

Thank you for your assistance- greatly appreciated.

Mahalo nui loa- Thank you very much.

Don)