DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (http://www.diychatroom.com/)
-   Building & Construction (http://www.diychatroom.com/f19/)
-   -   ICF vs. Wood Framed (http://www.diychatroom.com/f19/icf-vs-wood-framed-121328/)

JackOfAllTrades 10-26-2011 12:28 AM

ICF vs. Wood Framed
 
Going to build a custom 2-story home in Northern AZ. It will be built on a slab, no basement. The area can see some high winds (60MPH+) and there is a potential for some seismic activity (3.0 - 7.0 quakes), while very rare, there are some fault lines that can produce a 6.0 or greater quake every 150 years.

I like the ICF for strength and for providing better resistance to pest intrusion (mice, termites, scorpions, rodents) vs. wood frame.

So the question stands, should I go with a wood frame, 16" O.C, 2x6, shear paneling/OSB throughout OR go with the ICF?

The exterior, regardless if ICF or wood, will receive a stucco finish. Will utilize Styrofoam backing, chicken wire and then stucco finish.

Of course ICF is stronger in regards to wind loads but what about earthquakes? It seems that wood would be more flexible in quakes vs. ICF.

AndyGump 10-26-2011 12:35 AM

My personal opinion is to frame with wood.
Wind loading is really not a problem, seismic is the same.
Easier to build, much can be done ones self.
Less expensive.

ICF is a pain to get electrical and plumbing thru without highly skilled craftsmen (and women).

Of course there are advantages and dis-advantages to each but for my money...wood.

Andy.

ddawg16 10-26-2011 02:46 PM

My garage is wood framed with OSB for shear walls. If we have the big one, I have no doubts my garage will handle the shaking a lot better than my house.

The minute you nail those Struct 1 OSB panels to your wood framing...strength goes up quite a bit. With proper anchor bolts and hold downs....it's not going anywhere.

But don't just wing it using info from the internet. On a project of that magnitude, get an architect/Engineer to do the design...there is a lot more to it than just nailing 2x4's 16" OC.

concretemasonry 10-26-2011 05:03 PM

The flexibility of a wood structure can be a real problem, because it takes very little "flex" to crack the interior joints that are not a picnic to repair properly. Fortunately you do not have either heavy or frequent shakes. At least you do not have hurricanes and storm surges, the concrete or reinforced masonry unless you laminate 3/4" plywood on a both sides of steel plate as sheathing for severe life safety coastal conditions.

Dick

robertcdf 10-26-2011 08:51 PM

If you're doing it yourself then stick with woodframe, if you're building your custom home I would do ICF all the way. The insulation benefits and durability are awesome. Use steel for all your inside framing as well so you have perfect walls everywhere.

jklingel 10-26-2011 10:49 PM

"The insulation benefits...." Name two (being sarcastic; an old line). That is very dependent on how the heat is getting into the building. If the sun is providing it, fine, go w/ ICFs if you want to deal w/ the above mentioned concerns and you like the "feel" and have the money. If you are providing the heat, then ICFs may or may not have the R value needed for your area and/or your goals. This has been discussed here several times and on other forums. If you need high R, then ICFs need to be insulated on the outside. (Note: I heard a rumor of an ICF company making asymmetric blocks, which is very wise.) Alone, and you providing the heat, they provide no thermal mass advantage because the mass is in the middle of the insulation. As for bug proof, they are not; ants love styrofoam. As for quite, resistant to air movement, and tough, that they are. Remember, though, that air leaks are generally at the wall penetrations, not randomly located in the wall. Lastly, ICFs are environmentally rude; way too much petrochemicals and embodied energy in them.

JackOfAllTrades 10-27-2011 04:51 AM

Quote:

Originally Posted by jklingel (Post 757699)
This has been discussed here several times and on other forums. If you need high R, then ICFs need to be insulated on the outside. (Note: I heard a rumor of an ICF company making asymmetric blocks, which is very wise.) Alone, and you providing the heat, they provide no thermal mass advantage because the mass is in the middle of the insulation.

I will be putting a stucco exterior which will give me an R-Value of 20, just with the styrofoam stucco. The ICF will give me an R-value of 20. Adding together, I will have an R-Value of R-40. If fiberglass can be added when the interior walls are framed, I could be easily at R-50.

One thing is for sure, ICF homes have a 50%-70% reduction in utility costs compared to the same wood-framed home.

Quote:

Originally Posted by jklingel (Post 757699)
As for bug proof, they are not; ants love styrofoam.

The styrofoam they now use is bug/insect proof. They spray the styrofoam with a chemical. Besides 99.9% of the homes out in AZ use stryofoam because they use it when applying stucco. Even wood framed homes get styrofoam applied to the exterior, which then gets covered with a thin layer of stucco.

What I meant by "bug proof" is that an ICF home is resistant to termites and rodent infestation/intrusion. There is no way they can make their way through 8"+ of concrete. When the building is constructed on a concrete slab, the ICF walls and floors form one continuous surface; this keeps out insects and rodents.

Every stick built wood framed home I have seen gets invaded by rodents, scorpions, centipedes and even termites. Especially the area where I plan to build (rural). Rodents can gnaw through wood and scorpions make their way in through all the gaps in wood.

jklingel 10-27-2011 10:29 AM

Dense packed cellulose has borates, which deters insects and rodents; not sure about scorpions. I've never read anyone reporting mice poop and bug nests in cellulose, so I suspect the infested houses have fiberglass; SUSPECT. As for the 50% reduction in utilities w/ ICFs, I only read that from ICF people and anecdotes. The science, as far as I have read, and as far as I can reason, is just not there for them. That is not one of their strong points. A stick house w/ dense packed cellulose is cheaper and easier to build, for DIY folks, and more thermally efficient. There was no comparison when I ran the numbers for my place, but different places have different prices and different environments. ICFs are "the way" to go below grade, IMO. I built a foundation w/ blocks twice; never again. Even the first time through, ICFs were much faster, easier to handle, and no more expensive than blocks w/ foam installed on the outside.

JackOfAllTrades 10-27-2011 01:40 PM

Quote:

Originally Posted by jklingel (Post 757937)
A stick house w/ dense packed cellulose is cheaper and easier to build, for DIY folks, and more thermally efficient. There was no comparison when I ran the numbers for my place, but different places have different prices and different environments. ICFs are "the way" to go below grade, IMO. I built a foundation w/ blocks twice; never again. Even the first time through, ICFs were much faster, easier to handle, and no more expensive than blocks w/ foam installed on the outside.

I will have a contractor/builder putting up the home, whether ICF or wood, it will be done professionally.

Some good points have been made. Here is where I find wood framed homes lacking:

1 - Building in a wooded area and when using wood frame, there is ALWAYS intrusion through the walls by rodents and insects, ALWAYS. I have yet to see a wood framed home built in that area that did not experience rodent or insect intrusion. Where the wood foundation meets the concrete slab is a weak spot for intrusion. Rodents will gnaw through wood and enter into the cavities/walls of the home and nest there.

2 - Subterranean Termites are a problem out here. On a wood frame home it is always a constant battle in trying to keep them from eating you out of a house.

3 - Strength. While wood framed homes can be made stronger via ties, straps, headers, etc., they are never as strong as a 12" concrete wall. Only concrete structures can withstand 150MPH+ winds and flying projectiles (tornadoes).

4 - Fire resistance. In a wooded area, fires are a constant threat. A wood framed home is never as "fire proof" as a concrete home.

5 - Longevity. Concrete & masonry buildings stand the test of time. The longest standing structures in the world today are always made out of concrete. Wood rots, flexes, splits, especially the wood we use today is NOWHERE near as strong as the wood we used years ago. The framing wood we use today is less dense, weaker and holds more moisture compared to the older, more mature wood was used years ago. Back then the trees were 50-100 years old, nowadays we use trees that are 10-20 years old for building.

The above are some of the disadvantages I find with wood framed homes. While they make "treated wood" to prevent termite infestations, such wood is much more expensive to use in framing. Typically they use treated wood at the sill where the wood meets the concrete slab but the rest of the home is not treated wood. All termites do is walk over the treated wood and infest the non-treated wood above it. :huh:

How does one keep out the rodents with a wood framed home? Is that even a possibility?

jklingel 10-27-2011 02:11 PM

Jack: Those are some of the + and - of each, yes. As for "How does one keep out the rodents with a wood framed home? Is that even a possibility? " my understanding is that dense packed cellulose solves that problem. A good place to ask is greenbuildingadvisor.com. BTW: A pro bug killer told me that ants have zero fear of treated wood, so it won't help much, either. Concrete is fireproof, yes, but the foam is not and subsequent fumes are very toxic. I once asked, when I was considering using ICFs for the reasons you stated, if they survive a fire. The answer was "I doubt that you'd want to live in the stink left in the concrete, if the concrete survived an intense fire." Dense packed cellulose is a fire retarder, but I don't know if the stink in it would be any better than anything else. It may keep the fire from penetrating the wall, but would possibly have to be replaced because of the stink. I dunno. I do know that I dare not run my cutting torch on my garage slab or the concrete blows up in chunks. Bottom lines: Fires are pretty nasty, regardless of what is in their way. Their ain't no perfect building material for all situations. We have to pick "the best" (in our opinion) for our goals, budgets, and environment.

AndyGump 10-27-2011 02:19 PM

I think that you have made up your mind Jack.

ICF just might be the way for you to go.

Andy.

concretemasonry 10-27-2011 02:35 PM

Being cheap is easy if it is a short life structure. A little more spent during planning and construction is a good investment in the end. - Maybe that is why the developed world does not use wood as a major residential building material since they build to last.

woodworkbykirk 10-27-2011 09:05 PM

a previous poster said that icf's need to be insulated on teh outside, um they are thats the 2 1/2" of foam on the outside of the concrete.... hence I.C.F insulated concrete form......

with icf most regions require the installer to be licensed on the specific product via taking a 1 or 2 day course in order for it to pass inspection, it is a engineered product. personally im licensed both on Nudura and Arxx. mind you once you've used one brand most of them are the same.

for energy efficiency, icf's by far outperform wood framing.. case in point last year i built a 4000 sq foot vet clinic which was 90% icf. this building was replacing a 900 sq ft space. the owner showed us a copy of the energy costs for the first 6 months in the new space in comparison to the old space which was almost 1/5 the size. the new space's heating bill was 1/4" that of the old space

regarding being able to use it for earthquake zones. im uncertain. you will have to talk to the local supplier or engineers to find out if its ok to use, wind should be fine

JackOfAllTrades 10-27-2011 11:59 PM

Being energy efficient is key, mainly due to the rising costs of electricity and gas. Wood frame can be made to be energy efficient but ICF does provide an advantage to heating/cooling costs.

As one person mentioned, masonry has stood the test of time. In Chicago the homes that have lasted 100+ years are masonry. The same for the rest of the world, masonry structures have stood for hundreds of years. I believe these wood framed homes of today will be lucky to see 50 years before major work has to be done to keep them standing.

I will talk it over with my architect and engineer to see which direction I go, ICF or wood frame. I appreciate all the input! :thumbup:

woodworkbykirk 10-28-2011 03:44 PM

a key thing to remember is, no matter what the product used to build the house, a quality install is key... there are plenty of guys building houses out there. and from what ive seen only a handful do it well or above and beyond code. there are several builders in my region that do things as cheap as possible and then they wonder why 1/2 the homeowners are calling them 3 years later with all kinds of problems with their house. also following manufacturers guidelines for a proper install do wonders for a building... if you just throw things together the product will fail and then you have issues.. guys that think 3/8" gaps in siding is perfectly fine because caulking seals things there wrong.. caulking is only good for 1/8" - 3/16" gaps, its to seal not to be used as filler.. it dries out and cracks then water gets in

reasons like this wonder why i cost more than the other guy, 1) your getting a higher quality product, 2) if for some reason something does happen i will come back and fix it


All times are GMT -5. The time now is 11:05 AM.


Copyright 2003-2014 Escalate Media LP. All Rights Reserved