Insulated Concrete Forms (ICF) is an alternative to traditional wood framed construction. The forms consist of two pieces of foam connected together with plastic rebar. The forms fit together like lego blocks and as you stack, you fill with steel rebar and concrete. There are many benefits to building with ICF which I will discuss in this post.
- Quick construction
This was the primary reason why we decided to build ICF. ICF is a 5 in 1 step: the structure, continuous insulation, furring attachments, air barrier and vapour barrier are all completed at once with ICF. While you pay a little more upfront (compared to wood framing), building more efficiently ultimately saves time and money.
We decided to outsource the ICF to a local contractor however Brent will be completing all remaining construction. Since time is money, the quicker the contractor can get the structure up, the longer summer building time Brent has.
2. Energy efficiency
A close tie to quick construction is the improved energy efficiency. Concrete has high energy storage capacity with low thermal conductivity, it provides the most useful level of Thermal Mass. This helps to stabilize the internal temperature from day to night temperature fluctuations and provides a largely self-regulating environment. Reducing the amount of mechanical equipment needed for heating and cooling means less energy consumption, resulting in greater cost savings throughout the year. I designed the home using PassivHaus principals. I positioned the large backyard windows oriented towards the equator – which is South in the Northern hemisphere. This allows for passive solar gain. The overhang over the deck blocks out the high sun in the summer but allow for solar gain in the winter when the sun sits lower in the sky. This is all how I am hoping it will play out. Fingers crossed everything goes as planned! You
3. Large window sills
Due to the thickness of the wall, the window sills are so wide that I can sit in them. It looks so beautiful, like a castle. Since the jams are so wide we ordered our windows with no jams. This saved us money on the windows, however, now we must build custom jams.
4. No off-gassing
NUDURA, the ICF manufacturer we chose, emits no harmful CFCs, HCFCs or VOCs.
5. Low Waste
The waste resulting from the construction was so minimal that it only resulted in one trip to the dump. If the City of Ottawa recycled styrofoam, we would have been able to recycle all waste. Check with your local municipality to see if / where you can recycle styrofoam.
6. Natural Disaster Resistant
Last year our community was hit with a few tornadoes. I am curious how well our concrete ‘bunker’ would fair out if a devastating tornado hit. I think the roof might blow off but I think the overall structure would stand. Nudura’s website claims that it can withstand 250 mph winds
7. Quiet Interior
Once again, due to the thickness of the wall, the inside of your home will be very quiet. This would be very important to me if we lived on a busy road or in the city. Since we are in the country it is not too much of an issue.
8. Recycled Material
The plastic folding webs between the styrofoam in NUDURA Forms are manufactured from 100% recycled polypropylene and steel.
9. Fire Resistance
With a 6″ ICF thickness, NUDURA holds a 6 hour fire resistance rating.
Originally we were going to do the ICF by ourselves, however, due to my husband not going on strike, we decided to outsource. Nudura offers a day long crash course in the installation of Nudura ICF. Brent attended a course locally and felt confident in his ability to install. Guess we will never know if it was manageable enough to do on our own… Maybe we will try building a shed or a pool?!