Old garages around Boston usually fail from the ground up. A footing that reaches below frost and a floor that drains to the door are what keep a new one straight.
The slab and foundation decide how long a Boston garage lasts. Freeze and thaw is what breaks most old garage floors here: water gets under a thin slab with no footing, freezes, and lifts the concrete until it cracks. A new garage foundation starts below the 48 inch frost depth the state code sets, so the walls do not move with the seasons.
Most garages here get a frost wall or footings with a slab poured inside, on a compacted gravel base. We slope the floor toward the door or a drain so meltwater from cars runs out. Ledge, old fill and buried rubble are common on older lots, and each changes how the ground is prepared before the concrete truck comes. On a sloped lot, the high side may need a retaining edge so soil does not push on the wall.
We also replace slabs in garages that are still standing, which is common where the walls and roof are sound but the floor has cracked, sunk or tipped. The old slab is broken out, the base is rebuilt and the new slab is poured to a proper slope. Before any digging, Dig Safe must be notified at least 72 hours ahead, not counting weekends and holidays.
Garage slabs & foundations in Boston: common questions
How deep does a garage foundation go in Massachusetts?
The residential code sets the frost line at 48 inches, so footings reach that depth unless an engineer designs a frost-protected shallow foundation.
Why did my old garage floor crack and tip?
Usually because it was thin, had no footing and sat on poor fill. Frost and water lifted and dropped it over many winters.
Can you replace just the slab?
Yes, if the walls and roof are sound. We support the structure, remove the old floor and pour a new one.
How it works
- Free on-site estimate: Call, text or book online. We look at the lot, access and where the garage can go.
- Plans & written quote: Size, layout, materials and price in writing.
- Permits & site prep: We check what the job needs, then prepare the ground and the slab.
- Build & walk-through: Framing, roof, doors and finish, then a walk-through with you.