Re: Low cost, flexible Tiny Housing.
- I have been thinking of a way to make a SIP camper, with plywood and strong cardboard tubes. Fill the tubes with expanding foam, then slice off the excess so the ends are flat. Cut the tube into pieces 2-3 inches thick, depending on the thickness of the finished wall. Lay one sheet down, glue the tubes on every square foot or so with a construction adhesive, then glue the top sheet on. Then use the spray expanding foam to fill the space between the sheets. You would want to use the minimally expanding foam, the stuff that expands so strongly that it could warp your panels would not be ideal here. I'm thinking you would end up with a very strong, very light, very well insulated panel.I've been thinking about this for a while, to make a cabover camper for the back of my 11 Nissan Frontier 4WD. It would be light, strong, and well insulated, and edges would be fiberglassed similar to how Paul Butler works his plywood construction at Butlerprojects.com. Edges would be glued, screwed, then fiberglassed. I'm still working out the edges, but no rush; so far it's been an enjoyable mental exercise.I have been considering this since I read of a tiny house on a trailer built of SIPS. I like to make stuff, so mental wheels started turning. How could I make my own SIPS?Any thoughts/suggestions?Lauren
- Hi Laren and All,I was checking out prices yesterday and finding the same thing that spray in foam is too costly it seems. Thanks for the numbers. Still a good idea, just costs need to drop.In the boating industry we use special, mostly PVC foam core to avoid delamination as other foams break at the junction when under stress. Road loads/vibrations can be hard if the unit isn't fairly stiff and many RV's can be called anything but stiff.So it's back to gluing SIPs.There is not a chance of me ever using OSB as overweight and swells when wet, at least those sold here in Fla. I'd far rather use CDX instead. Nor do I use wood I have to cover with another layer for looks as just silly waste and extra weight, costs.I meant the 3/4'' ply as a form, not as part of a wall and see little reason to use over 3/8'' on any wall. My 34' trimaran hull is only 1/2'' and 3/8'' sides, deck and it stands the seas in hurricane speed storms without a problem. My next TH will have a 5mm thick wall though insulation, facing could be put on the inside or outside if needed.A likely SIP for me is 1/8''-1/4'' ply on the inside or outside or commercial building metal for the outside before it gets it's ridges. Or of rich alum is always good. Facts are ply has about jumped the shark. on price here in Fla with it going up 300+% in the last 7 yrs with 50% of the demand. What's up with that? Metal building siding is cheaper/sq' that 1/4''BC pine!!On the tapes, many that the tape part is only for laying down the adhesive and the plastic gets pulled off before gluing metal, wood, composites, etc. As for long life most cars, boats and planes have been held together for many decades including the Grumman Tiger that have been flying since the early 60's who's wings, body are glued together. Now whole airplanes are glue. So kinda a hard to say they don't work well.You might want to check and see what is available before saying tapes are not good enough. 3M among other sources. I like 3M because their products work and while not cheap, are reasonable.Jerry DycusFrom: LarenCorie <larencorie@...>
Sent: Thursday, May 23, 2013 5:41 PM
Subject: [shs-talk] Re: Low cost, flexible Tiny Housing.
Posted by: "jerry freedomev" freedomev@...
All things considered, I would rule out the idea of an inexperienced
owner-builder using spray foam to fill panels. There are just too many
uncertainties, like the expansion. Just one puffy panel would blow any
potential advantage. Amateur owner-builders have enough new skills
to master, without taking on the development of a complicated new
building system. Stacking and gluing sheet foam and OSB/plywood
is simple and should yield dependable results. I own a motor home,
built by Winnebago, that has had its metal/foam laminated panels
become delaminated. The motorhome industry has had a huge run
of law suits, because of their laminated panels (various materials)
becoming unlaminated. I think it would be unwise for an amateur
owner-builder to risk venturing into metal/foam laminated panels.
However, basic foam/OSB or plywood SIPs are a well proven
system that does not have delamination problems (due to the
rigidity of the sheathing) and can be easily produced, by simply
stacking, gluing, and weighting.
> Just a 3/4'' ply on each side as a buck with bolts going thoughMost SIPS seem to use something like 7/16" OSB. Framing around
> windows, etc to keep the wall from expanding until the foam cures.
the doors and windows with wood, would probably be a good idea,
too. As well as stiffening the walls, it would solidly anchor the doors
and windows to the walls. With foam sheets, simply glue up the walls
(in stacks) then cut out the openings after.
> You can join especially metal SIPs with various adhesive tapes,Tape can be a good way to seal air leaks at OSB SIP joints.
> glues with overlapping edges or a metal/etc strip over them.
\But, it is not a substantial structural connector between SIPs.
Longevity, without a lot of maintenance is an important issue
for houses, regardless of how big they are.
Natural Solar Building Design and
Solar Heating/Natural Cooling/Energy
Efficiency Consultation Since 1975
www.ThermalAttic.com (many new
photos and pages, coming soon)
Read my Solar house design articles in:
-Energy Self-Sufficiency Newsletter-
Home base-LittleHouses YahooGroup
Founder-WoodGas - Power from wood
Yahoo! Groups Links
<*> To visit your group on the web, go to:
<*> Your email settings:
Individual Email | Traditional
<*> To change settings online go to:
(Yahoo! ID required)
<*> To change settings via email:
<*> To unsubscribe from this group, send an email to:
<*> Your use of Yahoo! Groups is subject to: