The ICF industry has been manufacturing in America for over 40 years, concrete construction started around 2000 years ago, steel reinforced concrete maybe 130 years ago—but somehow ICF construction in New England is still considered a new concept. Stodgy old New Englanders are famous for being “late adapters.” That and the abundant forests around us keep us “stuck on the stick.” Cavity wall stick-framed construction uses the cheapest materials, and almost any half-skilled carpenter can frame a wall and stand it up. So it’s easy to see the appeal to stay with the stick.
When I first took up carpentry in the 1970’s wood was my thing and that was it. Hardwood, softwood, plywood, chipboard. That was my world. When I started contracting I had to open my mind to all materials: metal, glass, stone, concrete, gypsum, foam, vinyl—everything. But even as I got to know these other products I was still a carpenter at heart, and always tried to steer the job back towards wood whenever I could.
As my business and I matured I was asked to add a large 6000+ addition onto a local hotel. The existing building was masonry and concrete structure and the addition would be too, no stick framing allowed. I was anxious.
The plan called for exterior walls built with concrete blocks, 2” of foam applied over the exterior, and furring attached to the interior. I was getting a harsh education, as the masonry bids came back. All that money spent, and I still had to insulate and hook finishes on the wall.
Around this time a local guy I grew up with introduced me to Insulated Concrete Forms (ICF). The more I studied it the more sense it made. Structurally superior, more insulation, sound attenuation, fire resistant, and easy attachment for drywall. Everything done in one shot. Bang. Move On.
My customer, the owner with around 50 years of serious contracting experience, said in his thick Jersey accent, “yeah that’ll work good, use that.” It wasn’t a mystical leap of faith, he was just smart enough to grasp the obvious value of ICF.
As we begin to acknowledge the importance energy efficiency, durability and sustainability; we’re finally demanding a higher performance from our building envelopes. Yet we still cling to the to the stick. I see folks spending a lot of time on air sealing, with up to 3 layers of insulation. Infiltration barriers on the outside, vapor barriers on the inside, talk about laminations of labor. Consider this, wood is dead plant matter, organic material that you are encapsulating within synthetic materials in your attempt to boost thermal performance. Make one mistake with your moisture management and you’ve got serious, “who’s your lawyer?” troubles.
Insulated Concrete Forms have no organic material trapped within. Steel reinforced concrete is used to build the strongest structures on this planet. Concrete is brewed from mostly local materials, water, sand and stone. Re-Bar steel is 100 percent recycled and the ICF that we sell is 70 percent recycled material by weight and provides an unbroken plane of expanded polystyrene (EPS) foam totaling five inches thick.
While the R-value is impressive, the absolute airtight quality of monolithic concrete should not be underestimated. No gaps, seams, joints, to seal. Equally important is the “flywheel effect” of all that thermal mass. It takes a lot of energy, be it hot or cold to change the temperature of a heavy mass wall. This has the effect of moderating swings in the indoor temperature and reducing cycles of heating and cooling equipment. Combine ICF walls in conjunction with ICF suspended concrete floors and/or slab on grade, and you create an incredibly stable heavy mass structure. The ability for concrete to store heat makes geo-thermal and solar heating much more viable. I’ve built ICF homes that can be heated with 90-degree water.
ICF’s require a carpenter’s skill set and are more cost competitive than ever before. Stack, brace, pour, DONE! The product allows considerable design flexibility. Walk-in coolers, hot tubs, pools, root cellars, multi-story housing, basements, schools, and the most comfortable home you can own.
Don’t be afraid, un-stick yourself.
Joel Baker is President of VTICF, distributor of Amvic products.
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