Aerial view of a Mariner Construction ICF home on pour day: full-height ICF walls with window openings braced, concrete pump boom reaching over the building, and the mixer truck feeding it

ICF Homes & Foundations

Concrete Walls.
Warm House.

Homes and foundations built with Insulated Concrete Forms: foam blocks stacked, reinforced, and filled with up to twelve inches of concrete.

Get an Estimate Call (207) 495-7398

ICF homes & foundations

We build ICF homes and foundations across Central and Southern Maine and beyond, from excavation through forming, rebar, pour, waterproofing, and backfill.

Homes, footing to roofline
Foundations and stem walls
Retaining walls
Garages and outbuildings
Pools New
Commercial and agricultural structures

Gabe's finished ICF home in Mt. Vernon: white board-and-batten gable, red siding, and a deck, in winter sun — Gabe built his own house with ICF in Mount Vernon, Maine

Why use ICF blocks

An ICF wall is solid concrete, insulated on both sides, poured around the house in one continuous piece. There are no seams and no weak spots: the insulation is everywhere the wall is. The house heats for less, shrugs off cold snaps, and keeps the road noise where it belongs. And concrete does not burn.

Patented in 1966, and ordinary construction in Canada and the Alps ever since, in winters harder than ours. The same system builds schools, apartments, and hotels.

40–60% lower heating and cooling bills
75% reduction in air infiltration
10× stronger
200 mph wind resistance
4+ hr fire rating
STC 51+ around 3× quieter

The Process: An ICF House

Footing forms with rebar set in the excavated houselot — 01 Forming the footings

Stacks of white ICF blocks staged around freshly poured concrete footings — 02 Footings poured, blocks organized

First courses of ICF foundation wall stacked on the footings — 03 Building the first floor

Aerial view of first-floor ICF walls stacked on the foundation, fall foliage behind — 04 First floor ready to be poured

Concrete pump truck and mixer set up to pour the ICF walls — 05 Pumping the walls full of concrete

Second-floor ICF walls braced, window openings bucked, fall woods behind — 06 Second floor almost fully stacked

Interlocking ICF blocks stacked above a second-floor opening — 07 The interlock, up close

Roof truss hanging from a crane line above the ICF walls — 08 Flying the trusses

Aerial view of the house with trusses set and the gable sheathed — 09 Trusses set, roof taking shape

The ICF shell under snow, roof sheathed and wall brackets still up — 10 Closing in

Red clapboard siding going on over furring strips in winter — 11 Hanging the siding

The finished house in morning fog: white board-and-batten gable, red siding, and a deck — 12 Roofed and sided

The finished garage at dusk, moon overhead — 13 The finished exterior

The finished kitchen: white cabinets, dark countertops, patterned tile backsplash, and wide pine floors — 14 Warm, quiet, and ready to move in

What it costs

Installation is efficient by design: the forms interlock and stack true, so an ICF build may only be about 3 to 7% more than wood construction up front, a premium that comes back in the first three to five years. The heating bills run 40 to 60% lower, and a tighter envelope means a smaller HVAC system can condition the same house. Energy efficiency tax incentives may apply, and insurers sometimes charge less to insure a concrete structure.

Foundation only

The smaller job

A stronger wall and a basement that holds its temperature. The smallest way into the system.

Full exterior walls

Maximum benefit

Insulated concrete around the whole house. The full heating savings, a quieter house, and a structure that shrugs off wind, cold, and fire.

Block sales

Mariner is a dealer for BuildBlock, SuperForm, and Element, and we sell to contractors and homeowners alike: whether a builder is quoting a full foundation or an owner is stacking their own garage, the blocks come from a crew that installs them for a living.

Common questions

What's actually inside the wall?

Foam insulation on both faces, tied together through the core, and structural concrete filling the space between. The ties double as furring strips, so siding and drywall fasten to the wall the same way they would to framing. The manufacturer's cutaway:

Cutaway model of a BuildBlock ICF wall: continuous foam insulation on both faces, integrated furring strips and rebar ties, and a monolithic concrete core — Source: BuildBlock

Will it look like a concrete bunker?

No. A finished ICF home is indistinguishable from a conventional one. The forms are structure, not finish. The exterior takes siding, clapboard, brick, or stone exactly as a framed wall would, and the interior is drywalled the same way.

Is it harder to build with?

Different, not harder. Stack, brace, pour, instead of frame and sheathe. The work is in what happens before the concrete: bracing checked, rebar placed, corners square, because the pour makes it all permanent.

Does ICF only make sense in a cold climate?

ICF is effective in every climate. Continuous insulation and thermal mass cut cooling loads in hot regions the same way they cut heating loads here. In Maine the heating side is simply where the money shows up fastest.

Can I just build a really well insulated wood wall?

A very good wood wall is possible, and we build them. What framing cannot match is the combination of air sealing and thermal mass. A stud wall has a thermal bridge every 16 inches and no mass to buffer temperature swings. Those are properties of the assembly, not of how much insulation gets packed into it.

The longer version, covering cost, sound, moisture, siding, and winter pours: Why ICF in Maine.

Where we work

We build ICF homes, foundations, and specialty structures statewide for homeowners, architects, and builders — most often across Central Maine (Augusta, Waterville, Gardiner, Winthrop, and the Belgrade Lakes region) and Southern Maine (Portland, South Portland, Scarborough, Falmouth, Yarmouth, Cape Elizabeth, Freeport, Windham, Westbrook, Gorham, and Saco).

Get an Estimate

Tell us about your project, whether it's a full set of plans or just an idea. We follow up to talk it through, usually within two business days.

Gabe: (207) 495-7398 gabe@marinerme.com

Justin: (207) 495-7334 justin@marinerme.com

Concrete Walls. Warm House.