1370 Wilbur Avenue — Garage Rebuild

11 · Cost, Schedule & Procurement

Construction Cost Analysis

Revision 3 · September 2026

The detailed quantity takeoff is based on the coordinated frame geometry. All 88 members, 138 connection nodes, and 9 pier foundations have been counted from the model. Total estimate: $185,000–$325,000 (with GC overhead, profit, and 15% contingency).

Cost breakdown

#SectionLowHigh%
AExisting roof demolition$5,425$8,9753%
BPre-construction (eng + permits)$19,634$37,83414%
CFoundations (9 piers)$7,653$13,4605%
DSteel shop fabrication$16,712$28,11611%
ESteel erection (non-prevailing wage)$15,940$25,80011%
FSecondary roof framing$2,568$4,2882%
GRoof weatherproofing$9,601$14,9446%
HWall assembly (behind panels)$7,486$11,0555%
IInterior metal panels$10,510$18,4607%
JPainting (steel)$1,320$2,4391%
KLoft build-out$4,376$7,9953%
LElectrical$7,880$12,8005%
MSolar (net of 30% ITC)$21,333$27,36712%
NBalcony$5,645$10,4754%
ODoors & windows$4,500$9,5004%
PGeneral conditions$2,580$4,4002%
Direct costs$143,163$237,908
QGC overhead & profit (13–22%)$18,611$52,340
Total with GC$161,774$290,248
RContingency (15%)$21,474$35,686
Recommended budget$183,249$325,934

Rounded: $185,000 – $325,000. Midpoint ~$255,000.

Owner-builder (no GC, no contingency on GC markup): ~$160,000 – $270,000.

Where the money goes

Category% of direct cost
Engineering + permits14%
Steel (material + fab + erect)22%
Roof (framing + weatherproofing)8%
Walls (framing + insulation + panels)12%
Solar (net of ITC)12%
Electrical5%
Loft + balcony + doors/windows11%
Foundations + demo + GCs + contingency26%

Items needing real quotes

#ItemPotential swing
1Steel fab minimum charge−$5k / +$12k (2.65 tons is tiny — call 3 SD shops)
2Structural engineering scope−$6k / +$12k
3Prevailing wage trigger+$8k–17k
4Asbestos in old roof+$3k–6k
5Foundation complications+$3k–10k
6GC vs. owner-builder decision+$19k–52k

Procurement schedule

Long-lead items to order early: