Thursday, December 2, 2010

the plan?

Got the east edge piece of roofing up this morning....now comes the tricky part.  Seems the engineers who designed this building have not thought through all the details.  Just about figured out how to meld two different profiles of roofing - the trick is that the two different materials don't line up with their peaks and valleys.  The corrugated metal is a pure sign wave and the polycarbonate is a modified sign wave with a different frequency.  Who'd a thought the greenhouse design would be kinda like my electrical systems?  Hmmmmm...  48.74,25,0,C

15 comments:

William Scarbrough said...

Easy, Just make a wooden or metal template to sit between the two layers. Something like this:

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Spacer template here Spacer template
<><><><><><><><><><><><><><><><><><><

So that the two layers don't touch and the polycarbate does not touch the lower sheet metal.

JLP said...

Bet you never thought of the template. You get a lot of helpful suggestions.

JLP said...

There are some foam rubber sealers for corrugated metal and poly carbonates, as you are probably aware. Maybe you could double up on some of these to create a seal on both pieces. It could be too thick though. Just thinking.

rj said...

Rectify both waveforms to DC and use Inverter to restore to inphase AC

Scuba Steve said...

@rj - lol...

Michael said...

The foam idea is what popped into my head too. Not sure how long that would last up there though.

I also like the idea of making an 'adapter' by taking the two correct backer strips for each material and sticking them back to back. This kind of seems like the most elegant method, although would create a bit of extra thickness at the joint.

captaincrunch said...

John,

Attach the polycarb sheets to the main roof structure. Leave a gap between the metal roof and the polycarb roof. In fact overlap the polycarb by at least six inches or so.
This is the fun part. Stuff black pipe insolation in the gap between the two roofs. In the summer months remove the black pipe insulation to help ventalate out waste heat. That greenhouse will become a giant heat sink in the summer and Al Gore will flip out and blame your greenhouse for Global Warming.

Nick Cooper said...

check comment on your last post regarding Call for artists.

Guy Hodges said...

Expanding on what William and JLP suggested, get a set of closures (the foam sealers) for the metal and the poly. Then get a strip of flat 4" trim to lay under the high side and over the low side. Add some silicone sealer for safe measure and you're in business.

The foam closures and metal trim are readily available at ABCO here in Odessa.

austinmodhouse said...

here is how I would do it. C channel or square tube. overlap the clear over the metal with an inch or two of height difference.

take the C channel and run it along the top of the metal siding, possible w/ the metal going into the mouth of the C, and run the clear over with a slight overhang so all the run off falls beyond the material intersection

or just use a square tube the same way and butt it against the metal, same overhang.

clean and simple.

liteluvr said...

Maybe build a spacer of sorts to elevate the poly from the corrugated metal. Added advantage of allowing some extra ventilation... say 4-6" higher than the main roof.

Allen Hare said...

John, you have a lot of qualified engineers on staff here, it seems. I trust y'all can work out this small problem. Looking forward to seeing the resolution soon. Please include a good close-up photo of the fix.

Just noticed the overnight lows posted for the last two nights - man, that's chilly!

Best of luck with all.

Martin said...

Just a bit lost on the greenhouse. Where is the light let in.

delgrego said...

Erm, I think the light comes in through the huge gaping rectangular area in the roof there ;)

Martin said...

Thanks delgrego, I was expecting a traditional type greenhouse where the light comes in from all sides. Good to see someone open to trying something different