New plan we are maybe thinking of doing a whole house in ICf ,would appreciate any opinions, from experienced users,,,,,,,,thank you
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Excellent choice. I've worked with ICF's and if I were going to build a new house for myself I would use ICF from the footer to the rafters. The system we used is called Tech-block and it claims to be an R-25 wall.
As a personal preference I would not use an ICF system that does not integrate a continuous concrete slab as a finished wall.
Scott ,thank you for your reply, but not quite sure what you mean by your last statement about continuos slab,,,,,,,,,,,,,,,,,,,,thanks fred
I think Scott is saying that some ICF's form up a finished grid of concrete, with "holes" in between that are nothing but EPS all the way through. His preference (and mine) is a system that uses EPS "planks" or similar that allow you to end up with a wall that is continuous concrete topt to bottom, end to end.
You might check out http://www.tfsystem.com .
Fred, BEMW explained it very well.
A couple years ago FHB did an article on ICF's (not sure what issue) if you can get a copy of that issue the article has excellent explanations and diagrams concerning the different styles of ICF's being used.
Scott R.
I have it in my own walk out basement level and have used it on several other places. Worked next door to one where they did two stories wioth it. There are peculiar problems with going that high up but everyone I know who actually lives in one loves it.
Pro's -
No drafts
Easier to heat or cool.
Extemely quiet
Versatile
Con's -
hosts insects or vermin in some places
learning curve for first timers
Excellence is its own reward!
Are there any problems with installing windows in ICF products ? You mention a learning curve ,the builder im thinking of working with has used it for numerous foundations but i dont believe he has gone 2 stories high yet , but we are thinking of making it parade of home entry and learning experience for local tradespeople, Any coments on some things to look out for also in doing a parade of homes?.......thank you .Fred
Lots of bracing, puimp carefull but steady, be sure he undestands vibrating, have plywood scraps and screws handy in case of blowouts. Use spray foam to insure against them. frame window bucks from PT with anchors set into them.
Above all, think ahead.
parade of homes -you already know about timing and schedules then but it is important to have the finish crew ready to go with exterior stucco coat. Too long in the sun and the foam deteriorates..
Excellence is its own reward!
What Piff said , Only use forms that are open so that normal concrete can be placed. (imho) I also would not use forms that have metal ties ,go for the plastic ties to cut down on all the thermal bridges . use open bottom window and door bucks . ( eliminates air pockets) I also used a convayer truck instead of a pump . before placing concrete check all ties and bracing ,corners etc too be certain that every thing is done . make certain that all of the vent holes utility passages and the like are formed in. its alot easier to cut foam than concrete. Don
This looks like a good place to insert my ICF question. How do you put a brick veneer on an ICF wall? More specifically, what do the brick ties tie to? Do I use extra long nails, through the foam and into the concrete?
The ones I use have a composite face every eight inches that will allow a screw to fasten into it. It's like having a 1" stud @ 8"oc.
Excellence is its own reward!
Is there a standard for how much load the joint between the brick tie and the sheathing or framing has to be able to withstand? I just have this little movie running in my head where a brick over wood installation works fine but brick over ICF fails under the same load, with the nails pulling out of the composite nailer or the foam peeling off the concrete.
I can't answer with test standards and numbers. But I can say these 'plastic' things are dang tough. Personally, I would expect they would take at least as much pullout resistance as 1/2"CDX. Probably more since most ties I see are put on with 1"roof nails.
These compsite strips are not just mounted to the surface of the foam. They are part of the same grid that runs all the way through the wall. It has snap shaped saddles to fit rebar into and keep it aligned. So when you screw into the composite, it is part of the same structural connection in the concrete. It won't delaminate like ply or rot like wood. .
Excellence is its own reward!
There are two ways I have seen to deal with a brick veneer. One is to do the foundation with thicker concrete (i.e, 10" core vs 6" core), but that is obviously expensive. Another, which was used on my 'Blue Max' house is a special ICF form which kind of bows out 4" to support the brick. So it starts at the botton with a 6" core and ends at the top with a 10" core. Another 6" core block sits on top. The ledge has vertical and horizontal rebar, plus a zillion sittups to increase the strenght. A word to the wise, however, these are ugly as sin if exposed, so consider making the ledge below grade and putting a 4" concrete block filled with concrete to bring it above grade.
With the Tech-block system all that is need to make a brick ledge is to take a panel that is used for the footers and turn it upside down. This can be done anywhere in the wall.
Scott R.
Best piece of advice is chose your contractor extra carefully because poor workmanship is a major pain once the concrete sets up. Get a contract with lots of specifics like maximum out of plum, etc., and keep a big holdback. Do not accept boilerplate like "according to accepted practices, etc.)
Plan for extra agravation re plumbing and electrical. Nothing is done the way everybody expects, so do it yourself or pay somebody, either way you'll pay more.
Windows are a real slice too, with the 12" thick walls (plus brick for me), add in the variations in wall and every one hade to be customer fitted.
Other than than, very energy efficient, quiet, and real solid. Glad I did it, just wish I had been much more selective about the contractor.
I am a contractor near Nashville. I am in the process of building my first ICF house which my family will occupy. We have it bricked and will be sheetrocking this week.
I used the Reward I-Form and was very satisfied with the product and their assistance. We just finished the wiring and I did not see that it was much different than wood. We channeled out for the wire and located the boxes next to the ties. We used the boxes with tabs on them for screw mounting. I cannot see any reason plumbing to be an issue. I plumbed my house and just ran the supply and drain through the floor. The electrician cut the foam with a knife. If I had my way we would have used a roto zip. The electician I used is very particular and felt it would be too messy.
You do need to preplan for anything going through the wall and have your windows chosen prior to construction. I goofed up and made a couple of my openings too large. Somehow I got in my head the windows were 3/0 and they were 2/8. However it is better to be a little large that too small with ICF.
Danny
Plumbing is an issue because the exterior walls are solid. Even if you cut into the foam, sweating joints becomes a trick - either you melt the foam or the torch won't stay lit due to lack of air, or both. I had to figure out a number of ways of dealing with pressure pipes along exterior walls for things like hose connections. Similarly, vent stacks and the like required the removal of the insulation, which takes time and costs money.
Naturally, I made more grief for myself by going with a suspended concrete floor and readiant heating. Talk about plumbing challenges.
Of course there are many more electrical wires that have to be put into exterior walls so the the styrofoam has to be notched. Believe me, this adds up. Better yet, I saw an ICF house (fortunately in a different region from mine) where the inspector decided the electrical had to be in conduit or BX. I made my notches with a cheap electric chainsaw with a bolt of wood bolted to the end as a depth guage. Very messy, by styrofoam vaccums well. I used the plastic boxes with wings. I made a notch for the wings and the box is very solid once the drywal is up.
Of course the worst of my experience was fixing the crappy workmanship of the ICF contractor. A wall with a 3/4" bow in both axies was a particularly memorable joy. He told me he would shave the ICF to bring it into line. Never did. The worst was paying another $12K to have the mainfloor slab releveled. It was out by 3/16" over 4 feet in some areas. Hence the need for holdbacks: once the last check was cashed, I never saw him again and paid to fix up his mess out of my own pocket. Oddly enough, he sent a number of prospects over to my house as a reference. That cost him.