I’ve started a blog on building with SIPs (structural insulated panels)
Starting the 27th of November I will be making entries about my time at SIPs installation school.
You can link from the FH home page or you can go to www.sipbuilding.wordpress.com
jross — FH Editorial
Replies
I'm excited!
My wife and I are in the planning stages for a new home to be built in the mountains north of Phoenix. In a couple of weeks I will be meeting with the people at Premier to explore using SIPs. I will be watching your blog with much interest!
Thanks so much,
Burt
That sounds exciting. I'm curious, what kind of issues are you faced with as you confront the decision of whether or not to build with sips?jross -- FH Editorial
Basically a cost/benefit issue. I think the construction cost will be higher, and I know the energy consumtion will be a lot lower. Until I get a better reading on each, I don't know which way I will go.
I plan to general the construction myself, but that probably won't have much bearing on this issue.
There’s also the cost savings of less construction time. Though I think those savings are very job specific with lots of variables.jross -- FH Editorial
Take a look at my blog to see my SIP project. You'll have to go into the archives to see SIPs being assembled - about the 3rd or 4th week in July should do it. However, the neatest pics are the last week in June.
My builder is an experience SIP guy. He has come up with a few tricks of his own - the most interesting being how he does not use very many of the long "big red" screws.
For the folks in the Phoenix mtns, if that is a location with major day/night temp swings, something like a full T-mass house might be a better option.
Adventures in Home Building
An online journal covering the preparation and construction of our new home.
The day/night swing averages maybe 20-30 degrees most of the year. 85/60 in the summer, 65/35 in the fall, 50/25 in the winter.
You'll need to fill me in...full T-mass is what?
Thanks
T-mass is the "opposite" of an ICF. concrete-insulation-concrete instead of insulation-concrete-insulation.
There is a link from my blog to the T-mass site - I used that system for my basement. Take a look around and let me know if you want to know more.
http://jhausch.blogspot.comAdventures in Home BuildingAn online journal covering the preparation and construction of our new home.
Thank, I'll continue my research...
One of my biggest concerns about all of the "less conventional" methods I am considering is the level of expertise on the part of the local subs. I am building the house in a town of about 15,000 which is 75 miles or so from Phoenix, and would be reluctant to use any system that the local guys were not familiar with, unless I could be real sure of what I was doing.
I'll have a better handle on the "normal" systems locally in a couple of weeks.
Good point, local knowledge or experience with a system saves you from paying someone's tuition. On the other hand, an open-minded contractor and good factory support can bridge that gap.
One of the reasons I felt OK with T-mass for my basement was that it is very easy for a poured wall contractor to master.
http://jhausch.blogspot.comAdventures in Home BuildingAn online journal covering the preparation and construction of our new home.
Owner,
Little late to the party, but here is some info I found interesting.http://www.allwallsystem.com/Florida co.Concrete/insulation/concrete.Ease of install is emphasized.Pete
Those pics look great. I didn't see a crane on site. How were the sips lifted and how much was preassembled on the ground?jross -- FH Editorial
The builder has a loadall (off road telescoping forklift type thing) the panels were lifted onto the FF deck and then man handled from there. Most of the FF went up in a day with 3 people working (the builder, his helper, and me - OK 2.5 people working)
Only for the 17' panels around the greatroom did they break the loadall back out - and those they did with just the 2 of them. From what they told me, they lay the panel on the deck with the "top plate" just in from the edge; they put down the 2x6 on the deck; they then use the loadall to drag the panel out and away from the house, bringing the bottom of the panel closer to the edge; then, when the bottom edge of the panel clears the 2x6 on the deck, they lift up and back in with the loadall.
The only time we had a crane on site was for the trusses.
If you have questions you want to ask that need more than can be answered easily online, you can email me and I can call you or respond with my #
http://jhausch.blogspot.comAdventures in Home BuildingAn online journal covering the preparation and construction of our new home.
I just put a SIP roof on ICF walls. Here are several issues that I rarely see covered in articles or by SIP manufacturers.
1. The failure of any system that lets water contact the SIPs is more serious than most other types of construction. It can take far longer to detect slow leaks or condensation problems due to the sandwich characteristics. An undetected failure can turn the OSB into oatmeal before anyone realizes there is a problem. At that point, structural repairs are much more involved. I think the message is that more care and effort is warranted to insure proper construction details.
2. Long-term air tight seams are not a realistic expectation, especially on a roof. There is too much real-world installation tolerance and thermal movement to depend on adhesives. Thermal loss and infiltration is a less important issue than water vapor infiltration from the inside that condenses in the seam. Internal seam tape is a common solution.
This characteristic is a significant advantage of jumbo panels, up to 8' x 24'. The down-side is installation handling and damaged panels are more difficult to repair.
3. Finding an engineer experienced with SIPs is very important, if you need the PE stamp. Good ones can save a lot of money and provide a better product.
4. Detailed planning is far more important than with stick frame construction.
5. I rarely see construction loan costs factored into SIP cost justification. The fast assembly/dry-in of prefabricated panels should also be considered where there is a weather-window that can cause delays and material degradation.
6. I have heard criticisms from environmentally conscious individuals that the foam is petroleum based. Determining how much oil is needed to produce the foam in order to calculate the time it would take to break even on heating and cooling would be very interesting. I suspect that the savings would be achieved in the first month.
Don't take these issues as playing-down SIPs. I am a big fan. They have characteristics that need to be addressed to optimize their application, like any other building material. Fine Homebuilding is full of information on avoiding pitfalls of stick-frame construction. I hope your articles on SIPs do the same.
The question on localized failure is a good one. What happens if a tree falls on your house? How do you strip a rotten skin off and reapply another to the foam? Is that fix even possible?Water vapor infiltration seems to go hand in hand with questions about dew point and advantages and disadvantages about having a vapor barrier. On engineering; at the moment SIP construction is not covered in the IRC and so for most places in the country it is my understanding that a SIP structure has to get a stamp from an engineer (That’s an unchecked fact [UF] so don’t take it to bank) which is a substantial cost. Any window, door, or header that gets moved also has to get a stamp on it because in most cases the local building inspector doesn’t want to sign off on it without some backup. Totally understandable.The thing that I keep coming back to in my mind is that building with SIPs affects all the systems-- HVAC, plumbing, electrical, air exchange, etc.. The upshot is that it’s pretty complicated and needs to be thought through pretty carefully.I’m hoping to come up with some substantive evaluations as I go along. Right now I’m still trying to digest a big bird. Gobble gobble.jross -- FH Editorial
"Water vapor infiltration seems to go hand in hand with questions about dew point and advantages and disadvantages about having a vapor barrier."
This is not exactly true with SIPs. The EPS in SIPs is a vapor barrier with dead vegetable matter on both sides. The problem is that leaking seams will cause problems from both sides. Since house-wrap is the norm with SIPs, the problem remains interior vapor condensing in the leaking seam. Granted, the problem pails in comparison to a slow leak on a roof or flashing detail. Easily detected leaks in a stick frame may never be seen from the inside of a SIP structure.
I got some good information on this today. Basically seams, wall to roof interfaces and roof penetrations are very important to seal all these zones. Since a sips house is so tight, any place it can get out it rushes through. So if a roof penetration is not sealed, in all likelihood it will rot.jross -- FH Editorial
http://www.sipbuilding.wordpress.com
How do you strip a rotten skin off and reapply another to the foam? Is that fix even possible?
I'm picturing a significant water leak at a second story window due to improper flashing which has rotted out a significant amount of osb clear down to the ground. It would be interesting to know how such problems are addressed.
My guess is the foam is cleaned and a new osb skin is applied with either an epoxy or foam product. It would be interesting to see an engineer's spec sheet for the repair.
At the very least it appears that SIPs are a building method that either needs to be done very well or not at all. Unfortunately, the designer and installer aren't the ones responsible for keeping the water out and many GCs probably don't pay close enough attention to make sure it happens.
We all know owners who don't even consider replacing the roof until water leaks appear, which could result in half the exterior osb having given up the ghost.
It would keep me up at night thinking of average roofers reroofing a house 20 years down the road and poking a zillion holes in the top surface of the sip and ignoring proper flashing practices, as many roofer do.
I would bet money that the low standard of contemporary reroofing practices would create leaks of some kind in 20% of the SIP roofs over a 10 year period. That's not to mention the roofers that use questionable practices when throwing a roof on and rely on call backs to fix what doesn't "stick." They will love SIPs since there aren't any call backs (for water leaks on the ceiling)--until the rotten osb is discovered.
I can see SIPs becoming the framing of choice for those of us who are small builders since the framing and insulation are completed so quickly, leaving our time to concentrate on finish activities.
:-)
Beer was created so carpenters wouldn't rule the world.
--At the very least it appears that SIPs are a building method that either needs to be done very well or not at all--
In an ideal world, all building methods should be done well or not at all. Of course we don’t live in the ideal world but can only strive for one. In some ways, (and this is not a slam but a point of pride) the perfect world is the place that the FHB community aspires to live in.
jross -- FH Editorial
http://www.sipbuilding.wordpress.com
I got some good information on this today. Basically seams, wall to roof interfaces, and roof penetrations are zones that are important to seal properly. Since a sips house is so tight, any place air can get out it rushes through. So if a roof penetration is not sealed, in all likelihood it will rot do to condensation.
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At the SIPs school there is a strictly SIPs builder from <!----><!----><!---->Minnesota<!----><!----> who described two kinds of problems. One was a roof where the shingles leaked. A big section of the roof rotted. He stripped off the shingles and then the top layer of OSB. After he had cleaned out all the rot, he laid new OSB down and sealed it up properly; problem fixed.
<!----> <!---->The other scenario he described was a wall that had leaked up top. My details are a little fuzzy. I’m not sure if this was his house or his friend’s house. In any case, the fix was to temporarily brace up the ceiling and replace a 4-ft wide section of wall and then patch in the siding and interior drywall. As he is describing it, I am thinking it’s not much different that what you would do for a traditionally framed house.jross -- FH Editorial
http://www.sipbuilding.wordpress.com
How was the new osb bonded to the foam core on the contractor's field fixes?
Beer was created so carpenters wouldn't rule the world.
--I have heard criticisms from environmentally conscious individuals that the foam is petroleum based. Determining how much oil is needed to produce the foam in order to calculate the time it would take to break even on heating and cooling would be very interesting. I suspect that the savings would be achieved in the first month.--
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Here’s a thought about petroleum. From what I’ve read (and I’m no expert), it’s not what we consume that’s important, it’s what we discharge. Cars, coal, natural gas consumption all involve discharge of CO2s which leads to global warming and acidification of the ocean. But EPS in walls, per say, are not going to contribute to global warming more than the manufacture of fiberglass insulation or the OSB in regular stud frame walls for that matter.
<!----> <!---->I guess the logic is that a SIP wall is better than stud frame with batt insulation because the end product is more efficient.jross -- FH Editorial
http://www.sipbuilding.wordpress.com
JRoss,
Looking forward to see what your research reveals. We estimated a house for a client to be built here in Florida and getting the panels here as apparently there are no local maunfacturers was so costly, they decided against using SIPS altogether.
Mike
jross,
Having built with SIP's I can suggest a few tricks that will make building faster and easier.
First Most of the time I see SIP panels installed vertically. The trouble is that there is no real easy way to ensure that they are properly squeezed together. I wound up using straps screwed to each panel and then using the ratching mechanizm pulling them together.. that was extremely time consuming.
I later noticed a guy putting them together horizontally. Thus the weight of each panel helped ensure that everything was properly squeezed together. It really helped on the roof!
Once I screwed down the first panel every other panel could be set onto that one and the weight helped to ensure a better, tighter joint.. That plus I didn't need to worry about alignment or drift or any of the other problems that happen with vertical installation.
Second.
I drilled all my wire chases myself and cut all window openings myself. I don't care how carefull you are sooner or later one or the other will be in the wrong spot.
That plus you can take advantage of things because you can field modify the panels..
I didn't see the potential for a 11th dormer, untill I was nearly ready to install the panels, actaully I had many of the panels installed when I spotted the wonderfull view I missed. This is a house I'd been planning for nearly a decade. I'd lived in it for almost two decades. Yet because I hadn't been in that particular spot I'd nearly missed the oppertunity..
Because I was able to field modify panels it was simple to add the extra dormer.
Wire chases too are extremely simple to install yourself.. A spade bit with many extensions will get you thru the foam so quick it simply isn't worth risking having the factory do it for you..
I mean a 18 foot long drill bit seems a little silly but it goes thru in a minute or so. Then you snap a red chaulk line to show where it is and you are done.. Sometimes it's even possible to run the wire in place before you install the panel which saves climbing a ladder or something..
ACH (the R-control SIP folks) advised against horizontal panels. The designer said that on tall walls in rooms with high ceilings, a hinge point is created at the seam. I did not use SIPs for my roof (I did a truss roof with blown insulation), but I would think that it would be preferable to have a continuous panel from eave to ridge.
I don't doubt your experience at field installing wire chases, however, a beauty of the SIP system is speed. If you are still figuring wiring runs on outside walls on the days you are standing up the walls, that will slow things down. If the building project has a loose schedule and is a "labor of love", then, by alll means, modify the design as you go.
Speaking of chases, my builder advised that I use vertical chases over horizontal. There are a few areas where there is no choice, but most were vertical. I have heard where you can make a vertical chainsaw kerf in a wall to install a typical outlet "after the fact" if needed.
I partially agree with you on the field modify. My builder did cutouts on-site for any opening that did not req' an LVL header. This was less $ for me and it made the shell "more enclosed" until the windows can be installed. IIRC, your house is a timber frame, so I imagine you could easily field cut all openings.
http://jhausch.blogspot.comAdventures in Home BuildingAn online journal covering the preparation and construction of our new home.
jhausch,
That is only true if the walls are 8 feet tall.. Since it's relatively easy to make the walls taller your floor intersection winds up being in mid panel on say a 10 foot ceiling which strengthens the wall rather than makes a hinge.. *
I have part of my house with vertical panels and part with horizontal. The vertical panels went up extremely slow compared to the horizontal. Plus I am less than 100% sure that I have full joint closure on the vertical panels but I know that the horizontal panels are as tight as is possible..
I too thought that would be best I actually hoped for nearly a sealed roof so any rain couldn't leak in or if it did it only leaked at the seem and would run down to the sill and out with little or no leakage in the house.. The part that is vertical leaked like a sieve untill I put the ice and water on. The section of the roof I did horizontal never leaked a drop!
Frankly with regard to wire chases I only put in four wire chases in outside walls/ roof panels. All were done to provide a more elegant wire path than could be achieved than with any other method.. None will ever be able to be serviced easily.
*I also dropped the panels down below the floor thus providing me with full insulation right down to the bottom plate rather than at floor level.. since my floor timbers were 15 inches high and the subfloor was a full 2 inch thick with a finished floor a full inch on top of that I Gained an additional 18 inches of insulation that way..
The discussion that I'm interested in is SIP v. ICF.
Any thoughts?
Up front cost, construction cost, finished quality???
Also, how does each effect the other trades? Plumbing, Elec, HVAC?
How does each system effect the finish carpenters?
Sorry about such "big " questions.
F1
You’re right. That is a huge question but a question that I have thought of myself.
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Both systems strive for a tight envelope and high R-values. Both systems promote green building practices and thorough building science practices.
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A head to head comparison my not be appropriate either. Many houses use both technologies were they excel, say an ICF foundation and a SIPs main floor.
<!----> <!---->I think you are on the right track though. These are certainly some of the building technologies that are gaining popularity.jross -- FH Editorial
http://www.sipbuilding.wordpress.com
"Many houses use both technologies were they excel, say an ICF foundation and a SIPs main floor."
I don't want to put words in your mouth (and I probably did) but are you suggesting that Sips are superior to Icfs for "above ground" construction?
The two things that jump out at me are the structural considerations (winds -tornados and hurricanes) and thermal mass.
Second question: Ray Moore2g raised some past issues regarding sips for roofs
http://forums.taunton.com/n/find/findRedir.asp?webtag=tp-breaktime&mg=274B842F-21CD-4E77-8A9A-27DC34B87F3E
Any comments?
SIPs and ICFs are going to excel in different situations. There are so many site specific variables that saying definitively which one is better might be a waste of time.
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That said, the following link is a well researched project that opted for SIPs above ground.
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http://www.betterhomebetterplanet.com/
<!----> <!---->I heard (second hand) that one of the reasons SIPs are used above ground was simply because it was easier to handle the window and door openings with SIPs.jross -- FH Editorial
http://www.sipbuilding.wordpress.com
one of the reasons SIPs are used above ground was simply because it was easier to handle
That, and ICFs just aren't real handy for roofs <G> . . .
Now, if we are to compare systems, I'd think panelized versus SIP would make a better fruit-to-fruit comparison, since they can be used in similar ways.
It's a tad fruit versus vegetable to compare the thermal mass of ICF versus SIP; since neither is really very massy, other than in the foam. (Ok, ok, there's concrete i nthe ICF, but, it's really only about 20-25% of the volume.)Occupational hazard of my occupation not being around (sorry Bubba)
Faulted1
In my humble opinion having done a tremendous amount of research prior to using both systems. South of the Mason Dixon line I'd definately use ICF's again for the whole house. North of the Mason Dixon line the added insulational value of SIP's got the nod for above grade use. Building with either is quick and painless. There is a little more permanance with ICF's than with SIP's since modifiing a ICF involves either cutting or drilling thru concrete whereas with SIPs you are cutting or drilling thru mainly foam.. with modern cutting tools it's only a little more difficult to do than stick building..
Building with both require differant techniques than stick building. Not hard to figure out and learn but differant. Some in various trades are so used to doing things a certain way that they will never adapt. They will eventually fail. Recently an ICF home was designed and built for the same cost as a stick built house was quoted for. in the past there was a 2% premium but that has disappeared mostly with the successful contractors..
Since so many homes that use SIP's are timberframed I haven't found enough plain SIP built homes to do any real sort of price comparision. I know that when I did my estimating on my do it yourself timberframe the materials for the SIP were the same cost as the stick framing would have cost.. (at the time $2.57 a sq.ft. for walls and $2.85 a sq.ft for roof panels. With the recent increase in OSB prices those numbers are way low..