wiring in ICF

[Piper]

So I posted this question on the general board but didn't get much in the way of responses. I'm building an attached 24 x 32 garage with 11 foot ceiling. It'll be ICF and I need to run electrical. I know there's a special hot knife kit available for around $400, some guys say electric chain saw, others say router. I'm wondering if anyone has done this and what they did. If I have to buy the 400 kit I will but am wondering about "real world" experience.

Piper

 

[rsanter]

I like the idea of running conduit in the walls before the pour. any added electrical you have to install can be done in the foam.

I have seen the hot knife and also a rotozip to make the slot for the wiring

how about one of those round cutters you put on a grinder for wood carving, the outer edge looks like the chain of a chain saw

bob

 

[Tech Guy]

Piper I would go conduit as well. Makes life easier down the road.

 

[Piper]

I've done a bit of research on the conduit idea. While everyone says it's the "ideal" situation I've heard that as this introduces a lot of holes in the icf that the risk of a concrete blowout is really high. It's the sort of thing that I'm sure the pros can do quickly but I don't want to learn on my new addition. There are a few places were I will need to do conduit but for the bulk of the boxes I'm looking at somehow cutting the foam once the pour is done.

The main complaint I hear from folks is that the hot knife toggles on and off which slows cutting time. The really expensive ones don't (course I don't want to have to buy the expensive kit for 1 use). I'm wondering what would happen if I were to take a 120v hot water heater element and used that. I appreciate that they need a thermostat but I think I could fashion up something safe and cheap. Does a hot water heater element need to be in hot water to work? What'd happen if there was a handle and thermostat on it and it was used in the air? I've talked to a couple of guys who've used with success the electric charcoal bar-b-que elements for icf. I think the hot water heater element would be pretty similar but a much better shape.

Any experience??

Piper

 

[phiftyseven]

Don't use a water heater element. They will burn out if not submerged in water.

 

[hidollartoys]

I have cut a lot of foam with a fish filet knife (non-powered). The ones that you buy in the sporting goods stores and wal-mart(sporting goods area). Not to expensive and you can resharpen as required. If damaged throw away and buy new. Blades are 6 or 7 inches long and very thin.

 

[Jess]

The contractors I have seen use a small electric chain saw with a plate on the end of the bar adapted as a depth guage. Its a bit messy, but does the job. They spray foam the slot after the wiring is installed. I have never seen the hot knife idea used around here, but the ICF isn't that common yet.

Jess