Calculate the cost of building an accessory dwelling unit
BEGINWhat type of unit to build?
Include separate water and gas?
If you plan to rent out your ADU, you may want the utilities on separate meters, so your tenant's utility bills will be separate from yours.
NEXTIs home located on hillside?
Construction on slopes or hillside requires additional design and site prep work, like grading the surface or providing additional support for the structure. be separate from yours.
NEXT
We estimate that your project will cost with a likely range of
Below is a detailed breakdown of this estimate. You can change the ADU details to see how the estimate changes.
Low estimate  Medium estimate  High estimate  
Designs and permitting fees

$13,000  $13,000  $13,000 
Structural engineering report

$1,000  $1,000  $1,000 
Title 24 energy calculations

$500  $500  $500 
Hard construction costs

$77,350  $91,000  $104,650 
Contingency

$15,470  $18,200  $20,930 
Total cost  $107,320  $123,700  $140,080 
Cost per square foot  $268  $309  $350 
Low estimate  Medium estimate  High estimate  
Designs and permitting fees

$15,500  $15,500  $15,500 
Structural engineering report

$1,000  $1,000  $1,000 
Title 24 energy calculations

$500  $500  $500 
Solar installation

$15,000  $22,000  $30,000 
Hard construction costs

$116,688  $133,750  $150,813 
Contingency

$23,338  $26,750  $30,163 
Total cost  $172,026  $199,500  $227,976 
Cost per square foot  $430  $499  $570 
Low estimate  Medium estimate  High estimate  
Designs and permitting fees

$13,000  $13,000  $13,000 
Structural engineering report

$1,000  $1,000  $1,000 
Title 24 energy calculations

$500  $500  $500 
Hard construction costs

$97,350  $111,000  $124,650 
Contingency

$19,470  $22,200  $24,930 
Total cost  $131,320  $147,700  $164,080 
Cost per square foot  $328  $369  $410 
Low estimate  Medium estimate  High estimate  
Designs and permitting fees

$13,000  $13,000  $13,000 
Structural engineering report

$1,000  $1,000  $1,000 
Title 24 energy calculations

$500  $500  $500 
Solar installation

$15,000  $22,000  $30,000 
Hard construction costs

$97,350  $111,000  $124,650 
Contingency

$19,470  $22,200  $24,930 
Total cost  $146,320  $169,700  $194,080 
Cost per square foot  $366  $424  $485 
Low estimate  Medium estimate  High estimate  
Designs and permitting fees

$15,500  $15,500  $15,500 
Structural engineering report

$1,000  $1,000  $1,000 
Title 24 energy calculations

$500  $500  $500 
Hard construction costs

$116,688  $133,750  $150,813 
Contingency

$23,338  $26,750  $30,163 
Total cost  $157,026  $177,500  $197,976 
Cost per square foot  $393  $444  $495 
Low estimate  Medium estimate  High estimate  
Designs and permitting fees

$15,500  $15,500  $15,500 
Structural engineering report

$1,000  $1,000  $1,000 
Title 24 energy calculations

$500  $500  $500 
Hard construction costs

$96,688  $113,750  $130,812 
Contingency

$19,338  $22,750  $26,163 
Total cost  $133,016  $153,500  $173,975 
Cost per square foot  $333  $384  $435 
Low estimate  Medium estimate  High estimate  
Designs and permitting fees

$15,500  $15,500  $15,500 
Structural engineering report

$1,000  $1,000  $1,000 
Title 24 energy calculations

$500  $500  $500 
Solar installation

$15,000  $22,000  $30,000 
Hard construction costs

$96,688  $113,750  $130,812 
Contingency

$19,338  $22,750  $26,163 
Total cost  $148,026  $175,500  $203,975 
Cost per square foot  $370  $439  $510 
Low estimate  Medium estimate  High estimate  
Designs and permitting fees

$13,000  $13,000  $13,000 
Structural engineering report

$1,000  $1,000  $1,000 
Title 24 energy calculations

$500  $500  $500 
Solar installation

$15,000  $22,000  $30,000 
Hard construction costs

$77,350  $91,000  $104,650 
Contingency

$15,470  $18,200  $20,930 
Total cost  $122,320  $145,700  $170,080 
Cost per square foot  $306  $364  $425 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$14,000  $14,000  $14,000 
Structural engineering report

$1,500  $1,500  $1,500 
Title 24 energy calculations

$500  $500  $500 
Hard construction costs

$119,000  $140,000  $161,000 
Contingency

$11,900  $14,000  $16,100 
Total cost  $148,900  $172,000  $195,100 
Cost per square foot  $372  $430  $488 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$16,500  $16,500  $16,500 
Structural engineering report

$1,500  $1,500  $1,500 
Title 24 energy calculations

$500  $500  $500 
Solar installation

$15,000  $22,000  $30,000 
Hard construction costs

$168,750  $195,000  $221,250 
Contingency

$16,875  $19,500  $22,125 
Total cost  $221,125  $257,000  $293,875 
Cost per square foot  $553  $643  $735 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$14,000  $14,000  $14,000 
Structural engineering report

$1,500  $1,500  $1,500 
Title 24 energy calculations

$500  $500  $500 
Hard construction costs

$139,000  $160,000  $181,000 
Contingency

$13,900  $16,000  $18,100 
Total cost  $170,900  $194,000  $217,100 
Cost per square foot  $427  $485  $543 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$14,000  $14,000  $14,000 
Structural engineering report

$1,500  $1,500  $1,500 
Title 24 energy calculations

$500  $500  $500 
Solar installation

$15,000  $22,000  $30,000 
Hard construction costs

$139,000  $160,000  $181,000 
Contingency

$13,900  $16,000  $18,100 
Total cost  $185,900  $216,000  $247,100 
Cost per square foot  $465  $540  $618 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$16,500  $16,500  $16,500 
Structural engineering report

$1,500  $1,500  $1,500 
Title 24 energy calculations

$500  $500  $500 
Hard construction costs

$168,750  $195,000  $221,250 
Contingency

$16,875  $19,500  $22,125 
Total cost  $206,125  $235,000  $263,875 
Cost per square foot  $515  $588  $660 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$16,500  $16,500  $16,500 
Structural engineering report

$1,500  $1,500  $1,500 
Title 24 energy calculations

$500  $500  $500 
Hard construction costs

$148,750  $175,000  $201,250 
Contingency

$14,875  $17,500  $20,125 
Total cost  $184,125  $213,000  $241,875 
Cost per square foot  $460  $533  $605 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$16,500  $16,500  $16,500 
Structural engineering report

$1,500  $1,500  $1,500 
Title 24 energy calculations

$500  $500  $500 
Solar installation

$15,000  $22,000  $30,000 
Hard construction costs

$148,750  $175,000  $201,250 
Contingency

$14,875  $17,500  $20,125 
Total cost  $199,125  $235,000  $271,875 
Cost per square foot  $498  $588  $680 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$14,000  $14,000  $14,000 
Structural engineering report

$1,500  $1,500  $1,500 
Title 24 energy calculations

$500  $500  $500 
Solar installation

$15,000  $22,000  $30,000 
Hard construction costs

$119,000  $140,000  $161,000 
Contingency

$11,900  $14,000  $16,100 
Total cost  $163,900  $194,000  $225,100 
Cost per square foot  $410  $485  $563 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$15,000  $15,000  $15,000 
Structural engineering report

$2,000  $2,000  $2,000 
Title 24 energy calculations

$500  $500  $500 
Hard construction costs

$174,250  $205,000  $235,750 
Contingency

$17,425  $20,500  $23,575 
Total cost  $211,175  $245,000  $278,825 
Cost per square foot  $352  $408  $465 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$17,500  $17,500  $17,500 
Structural engineering report

$2,000  $2,000  $2,000 
Title 24 energy calculations

$500  $500  $500 
Solar installation

$15,000  $22,000  $30,000 
Hard construction costs

$237,813  $276,250  $314,687 
Contingency

$23,781  $27,625  $31,469 
Total cost  $298,594  $347,875  $398,155 
Cost per square foot  $498  $580  $664 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$15,000  $15,000  $15,000 
Structural engineering report

$2,000  $2,000  $2,000 
Title 24 energy calculations

$500  $500  $500 
Hard construction costs

$194,250  $225,000  $255,750 
Contingency

$19,425  $22,500  $25,575 
Total cost  $233,175  $267,000  $300,825 
Cost per square foot  $389  $445  $501 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$15,000  $15,000  $15,000 
Structural engineering report

$2,000  $2,000  $2,000 
Title 24 energy calculations

$500  $500  $500 
Solar installation

$15,000  $22,000  $30,000 
Hard construction costs

$194,250  $225,000  $255,750 
Contingency

$19,425  $22,500  $25,575 
Total cost  $248,175  $289,000  $330,825 
Cost per square foot  $414  $482  $551 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$17,500  $17,500  $17,500 
Structural engineering report

$2,000  $2,000  $2,000 
Title 24 energy calculations

$500  $500  $500 
Hard construction costs

$237,813  $276,250  $314,687 
Contingency

$23,781  $27,625  $31,469 
Total cost  $283,594  $325,875  $368,156 
Cost per square foot  $473  $543  $614 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$17,500  $17,500  $17,500 
Structural engineering report

$2,000  $2,000  $2,000 
Title 24 energy calculations

$500  $500  $500 
Hard construction costs

$217,813  $256,250  $294,687 
Contingency

$21,781  $25,625  $29,469 
Total cost  $261,594  $303,875  $346,156 
Cost per square foot  $436  $506  $577 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$17,500  $17,500  $17,500 
Structural engineering report

$2,000  $2,000  $2,000 
Title 24 energy calculations

$500  $500  $500 
Solar installation

$15,000  $22,000  $30,000 
Hard construction costs

$217,813  $256,250  $294,687 
Contingency

$21,781  $25,625  $29,469 
Total cost  $276,594  $325,875  $376,156 
Cost per square foot  $461  $543  $627 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$15,000  $15,000  $15,000 
Structural engineering report

$2,000  $2,000  $2,000 
Title 24 energy calculations

$500  $500  $500 
Solar installation

$15,000  $22,000  $30,000 
Hard construction costs

$174,250  $205,000  $235,750 
Contingency

$17,425  $20,500  $23,575 
Total cost  $226,175  $267,000  $308,825 
Cost per square foot  $377  $445  $515 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$16,000  $16,000  $16,000 
Structural engineering report

$2,500  $2,500  $2,500 
Title 24 energy calculations

$500  $500  $500 
Hard construction costs

$212,500  $250,000  $287,500 
Contingency

$21,250  $25,000  $28,750 
Total cost  $254,750  $296,000  $337,250 
Cost per square foot  $340  $395  $450 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$18,500  $18,500  $18,500 
Structural engineering report

$2,500  $2,500  $2,500 
Title 24 energy calculations

$500  $500  $500 
Solar installation

$15,000  $22,000  $30,000 
Hard construction costs

$285,625  $332,500  $379,375 
Contingency

$28,563  $33,250  $37,938 
Total cost  $352,688  $411,250  $470,813 
Cost per square foot  $470  $548  $628 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$16,000  $16,000  $16,000 
Structural engineering report

$2,500  $2,500  $2,500 
Title 24 energy calculations

$500  $500  $500 
Hard construction costs

$232,500  $270,000  $307,500 
Contingency

$23,250  $27,000  $30,750 
Total cost  $276,750  $318,000  $359,250 
Cost per square foot  $369  $424  $479 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$16,000  $16,000  $16,000 
Structural engineering report

$2,500  $2,500  $2,500 
Title 24 energy calculations

$500  $500  $500 
Solar installation

$15,000  $22,000  $30,000 
Hard construction costs

$232,500  $270,000  $307,500 
Contingency

$23,250  $27,000  $30,750 
Total cost  $291,750  $340,000  $389,250 
Cost per square foot  $389  $453  $519 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$18,500  $18,500  $18,500 
Structural engineering report

$2,500  $2,500  $2,500 
Title 24 energy calculations

$500  $500  $500 
Hard construction costs

$285,625  $332,500  $379,375 
Contingency

$28,563  $33,250  $37,938 
Total cost  $337,688  $389,250  $440,813 
Cost per square foot  $450  $519  $588 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$18,500  $18,500  $18,500 
Structural engineering report

$2,500  $2,500  $2,500 
Title 24 energy calculations

$500  $500  $500 
Hard construction costs

$265,625  $312,500  $359,375 
Contingency

$26,563  $31,250  $35,938 
Total cost  $315,688  $367,250  $418,813 
Cost per square foot  $421  $490  $558 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$18,500  $18,500  $18,500 
Structural engineering report

$2,500  $2,500  $2,500 
Title 24 energy calculations

$500  $500  $500 
Solar installation

$15,000  $22,000  $30,000 
Hard construction costs

$265,625  $312,500  $359,375 
Contingency

$26,563  $31,250  $35,938 
Total cost  $330,688  $389,250  $448,813 
Cost per square foot  $441  $519  $598 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$16,000  $16,000  $16,000 
Structural engineering report

$2,500  $2,500  $2,500 
Title 24 energy calculations

$500  $500  $500 
Solar installation

$15,000  $22,000  $30,000 
Hard construction costs

$212,500  $250,000  $287,500 
Contingency

$21,250  $25,000  $28,750 
Total cost  $269,750  $318,000  $367,250 
Cost per square foot  $360  $424  $490 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$18,000  $18,000  $18,000 
Structural engineering report

$3,000  $3,000  $3,000 
Title 24 energy calculations

$500  $500  $500 
Hard construction costs

$250,750  $295,000  $339,250 
Contingency

$25,075  $29,500  $33,925 
Total cost  $299,325  $348,000  $396,675 
Cost per square foot  $333  $387  $441 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$20,500  $20,500  $20,500 
Structural engineering report

$3,000  $3,000  $3,000 
Title 24 energy calculations

$500  $500  $500 
Solar installation

$15,000  $22,000  $30,000 
Hard construction costs

$333,438  $388,750  $444,063 
Contingency

$33,344  $38,875  $44,406 
Total cost  $407,782  $475,625  $544,469 
Cost per square foot  $453  $528  $605 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$18,000  $18,000  $18,000 
Structural engineering report

$3,000  $3,000  $3,000 
Title 24 energy calculations

$500  $500  $500 
Hard construction costs

$270,750  $315,000  $359,250 
Contingency

$27,075  $31,500  $35,925 
Total cost  $321,325  $370,000  $418,675 
Cost per square foot  $357  $411  $465 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$18,000  $18,000  $18,000 
Structural engineering report

$3,000  $3,000  $3,000 
Title 24 energy calculations

$500  $500  $500 
Solar installation

$15,000  $22,000  $30,000 
Hard construction costs

$270,750  $315,000  $359,250 
Contingency

$27,075  $31,500  $35,925 
Total cost  $336,325  $392,000  $448,675 
Cost per square foot  $374  $436  $499 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$20,500  $20,500  $20,500 
Structural engineering report

$3,000  $3,000  $3,000 
Title 24 energy calculations

$500  $500  $500 
Hard construction costs

$333,438  $388,750  $444,063 
Contingency

$33,344  $38,875  $44,406 
Total cost  $392,782  $453,625  $514,469 
Cost per square foot  $436  $504  $572 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$20,500  $20,500  $20,500 
Structural engineering report

$3,000  $3,000  $3,000 
Title 24 energy calculations

$500  $500  $500 
Hard construction costs

$313,438  $368,750  $424,063 
Contingency

$31,344  $36,875  $42,406 
Total cost  $370,782  $431,625  $492,469 
Cost per square foot  $412  $480  $547 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$20,500  $20,500  $20,500 
Structural engineering report

$3,000  $3,000  $3,000 
Title 24 energy calculations

$500  $500  $500 
Solar installation

$15,000  $22,000  $30,000 
Hard construction costs

$313,438  $368,750  $424,063 
Contingency

$31,344  $36,875  $42,406 
Total cost  $385,782  $453,625  $522,469 
Cost per square foot  $429  $504  $581 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$18,000  $18,000  $18,000 
Structural engineering report

$3,000  $3,000  $3,000 
Title 24 energy calculations

$500  $500  $500 
Solar installation

$15,000  $22,000  $30,000 
Hard construction costs

$250,750  $295,000  $339,250 
Contingency

$25,075  $29,500  $33,925 
Total cost  $314,325  $370,000  $426,675 
Cost per square foot  $349  $411  $474 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$18,000  $18,000  $18,000 
Structural engineering report

$3,000  $3,000  $3,000 
Title 24 energy calculations

$500  $500  $500 
Hard construction costs

$347,425  $367,000  $386,575 
Contingency

$25,075  $29,500  $33,925 
Total cost  $396,000  $420,000  $444,000 
Cost per square foot  $330  $350  $370 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$20,500  $20,500  $20,500 
Structural engineering report

$3,000  $3,000  $3,000 
Title 24 energy calculations

$500  $500  $500 
Solar installation

$15,000  $22,000  $30,000 
Hard construction costs

$430,113  $460,750  $491,388 
Contingency

$33,344  $38,875  $44,406 
Total cost  $504,457  $547,625  $591,794 
Cost per square foot  $420  $456  $493 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$18,000  $18,000  $18,000 
Structural engineering report

$3,000  $3,000  $3,000 
Title 24 energy calculations

$500  $500  $500 
Hard construction costs

$367,425  $387,000  $406,575 
Contingency

$27,075  $31,500  $35,925 
Total cost  $418,000  $442,000  $466,000 
Cost per square foot  $348  $368  $388 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$18,000  $18,000  $18,000 
Structural engineering report

$3,000  $3,000  $3,000 
Title 24 energy calculations

$500  $500  $500 
Solar installation

$15,000  $22,000  $30,000 
Hard construction costs

$367,425  $387,000  $406,575 
Contingency

$27,075  $31,500  $35,925 
Total cost  $433,000  $464,000  $496,000 
Cost per square foot  $361  $387  $413 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$20,500  $20,500  $20,500 
Structural engineering report

$3,000  $3,000  $3,000 
Title 24 energy calculations

$500  $500  $500 
Hard construction costs

$430,113  $460,750  $491,388 
Contingency

$33,344  $38,875  $44,406 
Total cost  $489,457  $525,625  $561,794 
Cost per square foot  $408  $438  $468 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$20,500  $20,500  $20,500 
Structural engineering report

$3,000  $3,000  $3,000 
Title 24 energy calculations

$500  $500  $500 
Hard construction costs

$410,113  $440,750  $471,388 
Contingency

$31,344  $36,875  $42,406 
Total cost  $467,457  $503,625  $539,794 
Cost per square foot  $390  $420  $450 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$20,500  $20,500  $20,500 
Structural engineering report

$3,000  $3,000  $3,000 
Title 24 energy calculations

$500  $500  $500 
Solar installation

$15,000  $22,000  $30,000 
Hard construction costs

$410,113  $440,750  $471,388 
Contingency

$31,344  $36,875  $42,406 
Total cost  $482,457  $525,625  $569,794 
Cost per square foot  $402  $438  $475 
Low estimate  Medium estimate  High estimate  
Boundary survey

$2,000  $2,000  $2,000 
Designs and permitting fees

$18,000  $18,000  $18,000 
Structural engineering report

$3,000  $3,000  $3,000 
Title 24 energy calculations

$500  $500  $500 
Solar installation

$15,000  $22,000  $30,000 
Hard construction costs

$347,425  $367,000  $386,575 
Contingency

$25,075  $29,500  $33,925 
Total cost  $411,000  $442,000  $474,000 
Cost per square foot  $343  $368  $395 