A-103 Cost build-up · in development
Know Your Cost.
The tax number is the easy half.
Every estimator on the internet will multiply your square footage by a number someone averaged in 2019. That is not an estimate, it is a guess with a dollar sign on it. This sheet prices the build line by line, at the grade you actually intend to finish it.
Preview · 600 sf addition, three grades
Illustrative figures. The live sheet prices against your town, your scope, and current CT supplier and labor rates.
| Line | Builder | Mid | High |
|---|---|---|---|
| Site & foundation | $22,400 | $27,600 | $34,800 |
| Framing & envelope | $38,900 | $46,200 | $58,500 |
| Roofing | $9,600 | $14,400 | $26,000 |
| Windows & doors | $11,200 | $18,700 | $34,500 |
| Mechanical, electrical, plumbing | $28,000 | $33,500 | $42,000 |
| Insulation & drywall | $14,300 | $16,800 | $21,200 |
| Interior finish | $24,600 | $41,000 | $78,400 |
| Construction subtotal | $149,000 | $198,200 | $295,400 |
| Per square foot | $248 | $330 | $492 |
| Resulting annual tax, Putnam | $2,070 | $2,754 | $4,104 |
Why grade matters more than square footage
Between builder and high-end grade, the same 600 square feet swings by $146,000, and carries roughly $2,000 a year in additional property tax with it. Square-foot averages hide that entirely. Choosing your grade up front is the single largest lever you have on both numbers.