Most garages around Boston are stick-built: wood framed on site over a concrete foundation. Kits, steel buildings and pole barns cost less up front by HomeGuide's national figures, but every one of them still has to carry the snow load and meet the frost rules of the Massachusetts code.
Every dollar figure on this page is a national figure published by HomeGuide, not a quote from us. HomeGuide publishes no Boston or Massachusetts garage prices. Lot access, ledge, frost depth and snow load all move what a real job here costs. Figures read in October 2026.
Is a metal or prefab garage kit cheaper than a stick-built garage?
Yes, a prefab garage is cheaper to buy, though the gap shrinks once it is set on a foundation. HomeGuide's modular garage page puts a two-car prefab unit at $7,200 to $26,000, or $11,000 to $37,500 with foundation and assembly, against $25,000 to $60,000 for a custom-built two-car garage. Garage kits run $2,000 to $20,000 for materials only. Around Boston, a kit must be rated for the town's code snow load and still needs a permit and a frost-depth foundation.
How much does a metal garage cost?
A prefab 20 x 20 metal garage costs $11,000 to $30,000 installed by HomeGuide's metal building page, the only metal-garage figure it publishes. Metal buildings in general run $20 to $50 per square foot for kit and installation.
Is a steel garage as durable as a wood-framed garage?
Both last for decades when built and kept up well; they fail in different ways. Steel does not rot or draw insects, but it dents, sweats inside in cold weather unless it is insulated, and rusts where salt gets in, which matters near the shore in Quincy or East Boston. Wood framing rots at the sill if water sits against it, so the sill must sit above grade on the foundation. HomeGuide publishes no price comparison of steel and wood garages.
Is a pole barn garage a good choice around Boston?
A pole barn, or post-frame garage, can work on a large lot but is uncommon in the city. HomeGuide puts pole barns at $15 to $40 per square foot installed and a 24x24 at $8,600 to $23,000. The posts have to go below the 48 inch frost line in the Massachusetts code, and the roof has to carry Boston snow. Post-frame suits a big shop or storage barn in Milton or Dedham more than a garage on a city lot.
Should I build a carport or a garage?
A carport is the cheaper choice and fits where a garage will not. HomeGuide lists a single carport at $2,000 to $7,200 installed and a double at $3,200 to $12,000, far below a garage. A garage locks, keeps out wind-driven snow and can hold a workshop. A carport keeps snow and ice off the car and needs less room on a tight lot.
Can a carport be enclosed into a garage later?
Yes, a carport can be enclosed into a garage if its posts, footings and roof can carry walls and a door. HomeGuide's carport-to-garage page puts the work at $10,000 to $40,000, with $10,000 to $25,000 for one car and $20,000 to $40,000 for two, and permit fees of $500 to $3,000. Most carports built on shallow post footings need new foundations under the walls first.
Can I add a garage to a house with no garage?
Yes, you can add a garage to a house with no garage if the lot and zoning leave room. On many Boston lots the answer is a detached garage at the back, reached by the existing driveway. HomeGuide publishes no price for adding a new attached garage to an existing house; the closest figure is $25,000 to $60,000 for an attached two-car garage.
Can a detached garage have a bathroom and plumbing?
Yes, but a bathroom means water and sewer lines, and in Boston's climate those lines must be buried below frost and kept from freezing inside. HomeGuide lists plumbing at $450 to $1,800 per fixture. A bathroom in a garage can also bring more questions from zoning if it starts to look like a dwelling, so check before you plan one.
What does a workshop garage need?
A workshop garage needs more power, more light, more height and some heat. Plan a subpanel, outlets on every wall, a deeper slab edge if heavy machines go in, and insulation if you work in winter. HomeGuide's outbuilding page says a 200-amp subpanel for power tools and welders adds $2,000 to $5,000. A wider side door makes it easier to move lumber in and out.
Does a prefab garage fit on a tight city lot?
Sometimes. A prefab garage still has to be trucked in, and some are lifted into place, so the driveway width, wires and trees decide whether it can reach the back of the lot. HomeGuide lists delivery at $5 to $10 per mile. Where a truck cannot get in, a garage framed on site is often the only way.
Want a number for your own lot? We visit, measure and put the scope and price in a written quote. Call or text (617) 326-7524.