My architect has designed a house with an inside corner which is "bumped out" 5' on each side in order to have windows on each side of this corner to let in lots of light. I want to build with ICFs but am considered that this corner he has designed won't work with ICFs. Most manufacturers have 90 degree corners that are on the order of 32" x 16" or so in length.

The Prescriptive method for ICF in residential construction states that a minimum length of 24" solid wall segment is req'd extending the full vertical height at corners. I'm having trouble visualizing this. Does this mean the corner wall can be 12" length on each side and the corner forms can be cut to accomplish this?

Is it possible to build this corner bump out with ICFs in order to have good sized windows on each side?

Thanks for your help.

The prescriptive method and now the IRC have been written to allow the layman to build a basic house with it's allowances or tolerances. Your top (lintel) and bottom bars are required to pass the opening by a minimum of 24" to maintain structural integrity. Anything less requires a calculation by an engineer. What your architect is drawing can be acheived with an engineers review - most likely some form of cage will be required.

What you are describing we do all the time. Don't let this stop you from building ICF. The prescriptive method and 2006 IRC are complicated and unforgiving. The "generic" engineering that manufactures use/give are much easier and forgiving. Offhand I'd say Logix, NUDURA and Reward have the best engineering.

Thanks for your responses! I have been keen on ICF for a while, but my architect is not very keen on them for use in Missouri, thinking that the cost/benefit over 2x6 with blown cellulose is not worth it.

StLouisZ, After the heavy weather, i.e., winds and tornados, that has passed thru Missouri and neighboring states, you might ask your architect if he's entered the safety and security of your family into the cost/benefit equation. We're going to build in rural Kansas and structural integrity is the most important characteristic we looked for. Wish it was a bit less expensive, but.... Dave