DIY SIPS?

[azkateo]

Hi, would like some info regarding an idea I have to save money - would like to build the 14x24 cabin with SIPS but my location is very remote and besides SIPS are, as near as I can figure, $450 per 4x8 panel - too much!.  SOooo I was thinking of building my own SIPS from exterior ply or OSB, gluing in 2 sheets of 2" rigid foam from local home center and then gluing on interior OSB.  I know I would have to trim the rigid foam sheets and probably remove the film from it as well as find the right kind of glue for laminating them all together.  I would use either 4x4  or 2-2x4's for the connecting studs between panels. As with regular SIPS, the panels would sit over the bottom plate which would be 2-2x4's.  Input welcome!

[MountainDon]

  azkateo

It has been done, sort of. The Country Plans main page, Owner's Gallery has a feature on such a venture, HERE.

The Cody Cottage was built from panelized wall section. There were not foam insulated but that's simply a detail as far as I'm concerned. The idea remains the same.

This idea has come up in various forms on this forum before. The major drawback for many is hauling the panels to the worksite. Sometimes it's a long ways away and over rough roads. You're going to have to judge the number of trips and the degree of difficulty. Then there's the question of handling the panels and putting them in place.  However, the idea can work.

We have one member who is planning a project similar to the Cody Cabin but on a smaller scale. As far as I knpw it is still in the planning stages. Watch the Owner-Builder projects section.

[glenn kangiser]

John has some info on Poor Mans SIPs here somewhere.

SIP article on PDF's http://www.countryplans.com/InlinePDF-2.html

[firefox]

OK, here is the scoop on DIY SIP panels: Yes it is possible to make your own panels, although it is not as simple as it first appears.

The first thing to understand is that the panels cannot be used in an area where you need permits if you make them yourself.
They have to have all kinds of certifications which require testing et al. We are talking 100s of thousands of dollars.

The second thing is that since they are "Structural" you need to do your homework or your hose will fall appart. It is not a matter of
just gluing the stuff together. It needs to be done with a large amount of preasure.

Now that I have voiced the warnings which you should not take lightly, there are two methods of making your own that dont involve
a huge capital outlay.

First is used with the EPS type foam and consists of building a frame that you can assemble the pieces in, place the glue, activate with water, and then cover and apply a strong vacumn for a specific time. Obviously this is over simplified, but that is the general idea.

Second is with PU type foam. This is a little trickier but essentially you build a restraining bed to assemble the pannels in, put in the two part PU in exactly the right proportions, quickly chain up the constraints TIGHT and the PU will expand to fill the void.

The key thing here is that you have to do your homework and understand the process. This is not for the faint at heart, but it can be done.

I would not advise trying to bond two sheets of foam together, You will have enough problems bonding the foam to the OSB or Plywood.

Note, you can use galvalume sheets instead of the OSB. This makes a big difference if transport weight or termites are an issue. You will need to pay special attention to connection details so that you do not get thermal bridges.

There is a third alternative that involves using steel hat channel and special screws to make a panel with the EPS sheets. It is not strictly speaking a SIP in the traditional sense, but it is structural and it is insulated and it is a panel. The structural is essentially the way the steel hatchannel is used as opposed to the combination of the foam and the outside laminate.

More info exists on the SIPs forum but you will have to weed through all the posts that go back a few years to get enough info to be usefull.

Hope this helps,
Bruce

[MountainDon]

You've distilled that info nicely Bruce. 

It's enough to make me want to stay with conventional stick framing. Well maybe not completely conventional; 2x6, 24" OC for the cabin.

[firefox]

Thanks Don! I'm trying to pay back for all the wonderful hellp you all have given me!
I hadn't meant it as a discouraging effort. I think it is a great way to go. I just didn't want someone
getting in over their head and loosing everything for lack of a heads up.
Bruce

[MountainDon]

I don't look at what you posted as discouraging as much as being a realistic statement. Although the reality of what is necessary to produce strong effective SIP's was discouraging. SIP's have advantages.

It's not as simple as erecting standard framing, but once completed properly may bring great rewards with air tightness, insulation value and so on.

[azkateo]

   Thanks for all the great input - but now I realize there may be some folly involved with that scheme!   HOWEVER, I have found a Thermasteel supplier here in AZ - they make a nifty wall panel system which is then coated w/a stucco product...here is their website:  www.thermasteelcorp.com

[firefox]

I think Thermasteel is one of the better companies. You will still need to do your homework, since although this is a relatively simple way to build, it does have its little quirks, so like anything else you need to pay attention to details and not cut corners. I think in the end you will really have something you like very much.

One very important warning. They have two methods of attaching the panels to the sil plate and the roof.
Do NOT use the channel method. This is a major thermal bridge and will throw away the extra money you paid to have the good insulation in the first place. Note that they show another method that consists of two angle sections, one on each side. This keeps the insulation in the middle without bridging from inside to out.
There will still be a wood thermal bridge but that isn't anywhere as bad as the channel.

When these guys first introduced their product they only had the metal channel track, but this was brought out in the SIP forum and I now see they have corrected the problem. I am not sure why they still keep the channel specs there unless it is for very moderate climates.
Bruce

[MountainDon]

Hi, would like some info regarding an idea I have to save money -

I re read your original post  azkateo.

I don't think any of the ideas will do what you stated in your first line.

[glenn kangiser]

Save money -- how about 2x4 studs on 24 inches - standard fiberglass insulation and a layer of foam of your choice thickness around the outside to insulate the studs - tape the joints - screen wall outside under your siding.  Should be similar in performance to SIPs at a fraction of the cost.

[Erin]

I'd pretty much given up on the idea that the owner builder could make their own panels, so I've followed this thread with interest.

Anyone read glenn's PDF link, yet?  A House of Her Own?
The home owner was inspired by Alex Wade's panelized system...  I read the article, but nowhere did it tell us how to make a panel so I kind of put it out of my mind.


Well I checked out a book from the library a couple of weeks ago, with a bunch of others, and didn't really pay any attention to it until yesterday.  It's called Guide to Affordable Houses by Alex Wade.  1984, Rodale Press.
Sure enough, his book deals primarily with panelization! 
Not SIPs, in that they're not structural, but SSPs.  Stress skinned panels.  They're for timber framed houses, but all of the other benefits are still there.  Speed and ease of construction, super-insulated, etc.    Plus it deals with how to install, put in windows/doors, electric chases, etc, etc.
Not only does he teach how to create and deal with panelizing, but also gives several very specific house plans that you could easily start building with tomorrow.  Post and beam sizings, foundation requirements, and so on.

But most importantly is the four or five pages, with step-by-step illustrations, that tell you exactly how to build your own panel with a frame, plywood/OSB back, EPS foam and topped with more ply or sheetrock!   

So where do you find EPS foam?  Is this the type of thing you can find at Menards? 

--Erin

[mvk]

Erin
EPS is that blue or pink foam that comes in 2'x8' t&g sheets the thickest I've seen is 2" but if you search I guess you can get it in a lot thicker. You can get it pretty much anywhere around here. My first post was about homemade SIP's or as you correctly said stress skin panels and someone said you can get it 4' thick. I have enclosed several porches that I built for people like this: 4x4 posts 4x6 top plates/beams 4x6 rafters with everything on 4' centers. I screwed sheet rock to the outside of the posts then 2 layers of foam I used the foil covered stuff because it had a higher R value one sheet vertical one horizontal these I glued with construction adhesive to the sheet rock and to each other and I taped the seems with metal tape. I then strapped it and put on the siding. I think it worked out well no Sheetrock seems to tape just screw holes . I thought of it for a house but there are all kinds of structural problems as far as code issues. I like the proportions of 4x4's, still. I think if I was building a small hunting/fishing camp and would be heating part time with wood I would do this and only use 2" of foam. When I was exploring this for a house I think I figured that I saved about $2-2.5 a square foot for walls.
Mike

[Erin]

EPS is that blue or pink foam that comes in 2'x8' t&g sheets

Oh!  That stuff!  In which case, yes, it's readily available. Woohoo! 
And I'm off and running again... lol

[mvk]

Erin
Actually I may have that wrong the blue and pink stuff is extruded the beadbord stuff might be expanded thats one of the foams used in some of the SIP's the other being the stuff that is usally covered with foil which is what I used and has a higher R value. But if I was making my own panels I wouldn't use the beadboard I would use either the blue pink stuff or the foil faced kind. Guess I maybe got you confused, got myself confused, maybe Don or someone will tell you and me what I mean

Whats your aim a high level of insulation, gets cold out in those sand hills, pretty country though, wish I had spent more time out there. Been through it a time or two, my wife and I just kind of meandered around there once she didn't like it much but I did. Good luck to you and your family with your homesteading hope it works out for you

Mike

[MountainDon]

Foam insulation can be confusing.

The white stuff is usually Expanded Polystyrene. When you look at it you can see the beads that it is composed of. It absorbs and retains moisture.  For that reason it really makes lousy insulation if it can absorb moisture from the atmosphere. Think bead board = bad. (my memory trick and opinion) Expanded Polystyrene is known as EPS.  EPS is borate treated and because of that is sometimes recommended, but it still have the water absorption problem.


The Blue and Pink rigid sheets of foam used for insulation are Extruded Polystyrene. (Dow = blue, Owens-Corning = pink). It is impervious to water. Extruded Polystyrene is known as XPS.

XPS is stronger, both compressive and tensile, has maybe 25% better R-value, better water resistance and cost more.


Regarding the foil faced foam products, I can't say for certain but possibly the reason it has a higher R-value is that the foil may reflect radiant energy rather than absorb it. I haven't looked into the product at all so can't say much about it. However, some of the foil faced "aero-cell" insulation products require an air space to achieve their full R-value rating with the radiant barrier effect.     I just mention this for info.

[John_C]

Woohoo!  ......
And I'm off and running again... lol

Just curious Erin, why do you want to do stressed skin panels?

My experience with panelized construction is that it is meant to be a way to turn house construction into an assembly line operation like cars are built. Even in the industry the bugs get worked out over a couple houses.  There are few advantages and several pitfalls for the individual builder constructing one house. Errors and omissions become a real headache, and it's very hard to make changes after the drawing board stage. The panels get heavy pretty quick and its easy to loose any time savings once you are on site.  If you have inspections to deal with they are likely to require an engineer's stamp once you deviate from proscribed practices.

I'm with Glenn on this...  Stick construction, fiberglass insulation and foam board. If you want to build panels at home and transport them they could still be a variation of frame walls.

[Erin]

Thanks for the clarifications Don.

And John--Why?  Primarily for speed of getting dried in. Secondary is insulative gains.
And inspections--the only thing we might be inspected for is septic.  And it's equally likely "inspection" there will consist of nothing more than showing our plans and getting a "Looks good."

What can I say?  Wade really makes a good case.   

[John_C]

Erin,

"Alex Wade" sounded familiar so I googled him.  I used to own his book

30 Energy Efficient houses you can build.
http://www.amazon.com/30-Energy-Efficient-Houses-You-Can-Build/dp/0878571914/ref=sr_1_1?ie=UTF8&s=books&qid=1207541112&sr=1-1

I got a lot of ideas for my current house from that book.  The houses by David Wright were especially interesting. I loaned it to a contractor friend former friend and never got it back. 

[MountainDon]

I'll just put my 0.02 in here...

How far will you have to transport the panels? Or will they be built on site?

What will the skins be? Will the panel sections be water tight as individual pieces or will they have to be kept out of the weather while they are built one by one and stored?

I had my hands on that book once at our library, but didn't take it out as I had too many other irons in the fire at the time. Since then, the books gone missing/stolen/whatever. I would like to see it out of curiosity.

I actually gave some thought to using a panelized process for the cabin. However, the transportation was a big problem. Handling large panel sections I saw to be a potential problem as K and I are to be the main work force. As I thought through my plan it seemed that window sizes and positions that we wanted would be problematic. It seemed I would have to compromise some things in ways I didn't want, or have some too large to handle sections.

It seems to me if one is building their own insulated panels, allowing for electrical, plumbing and heating requires a greater degree of precision and detail in the planning than with conventional stick built. If the electrical, plumbing, heating are contracted out you might have more difficulty finding tradesmen willing and able to adapt to the differences.

No matter what type of walls are erected, nothing is dried in until the roof is on and dry. 

I don't mean to rain on the idea, I see challenges that I personally don't want to tackle. I know I can erect conventional stick walls working from detailed drawings. OMMV

[Erin]

It seems to me if one is building their own insulated panels, allowing for electrical, plumbing and heating requires a greater degree of precision and detail in the planning than with conventional stick built. If the electrical, plumbing, heating are contracted out you might have more difficulty finding tradesmen willing and able to adapt to the differences.

You'd have to read the book to appreciate this, Don, but everything is covered.  It's much like building a straw bale house in that you try to put everything in interior walls and anything that has to be exterior can be put in exterior chases (or under mouldings,etc). Though it's also explained how to put chases in the foam if you must.

The basic principle is a timber framed house.  Which is the direction I've been leaning for over a year. Not only do I like the versatility of no interior load-bearing walls, but I love the look of a framed house.  The roof can be placed before the walls and we'll probably do a more or less traditionally framed roof for the simple fact that thinking about hoisting heavy, pre-made roof panels makes me more than a little nervous...  Panelization will probably be done on-site (in the basement or on the floor decks) to avoid having to haul them anywhere.

The timbers are placed on eight foot centers.  Ie, one panel (8'x8') will cover each span.
I know I can erect traditional stick walls, too.  But I also know I can do this, too. 

[firefox]

Hi Erin, I know you will have fun with this. I am also looking forward to making my own panels.
Just curious, how do you handle the thermal breaks at the wall roof interface?
Also, is the timber framing on the outside or the inside of the panels?

You might want to consider making roof panels with galvalume  bonded to EPS which is then laid on the roof
framing. This is then light enough to handle and gets you dried in quickly.

Bruce

[Erin]

I'll confess we don't have all the specifics worked out yet.    More reading, more research!  I've never even heard of galvalume... Have to go check it out.
The panels are placed on the *outside* of the frame, because afterall, the impressive posts and beams are part of the desire for a timber framed house.
Seriously, look into Wade's books.  (There are several available at Amazon from used book sellers for about 20c plus shipping!)  The pdf article glenn linked to on the first page gives a really good overview of how the process goes together, though. 

[MountainDon]

The panels are placed on the *outside* of the frame, because after all, the impressive posts and beams are part of the desire for a timber framed house.

Outside? Or between the timber framing so the timbers are still visible?

[Erin]

look at the PDF article.  There are two(?) photos that show what it looks like. 
The panels are nailed to the exterior of the frame and butt up against each other.  From the outside, you'd never guess it was timber framed.  The frame is visible from the inside