Has anyone tried this unusual type of SIP?
A potential client is pre-sold on using it. I have a hard time seeing the benefits over conventionally-framed, exterior-foamed assemblies, or double stud wall assemblies. Any first-hand (or unfounded) opinions?
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I asked about this product as well a few years ago.
Much of the criticism/suspicion evolved around the "true" finished R-value of the wall. 5.5" Raycore claims R-38.5! It would seem general consensus is the manufacturer may be exaggerating their claims (what else is new) seemingly not considering thermal bridging and window/door headers among other things. Their staggered product with external rigid insulation would seem the best arrangement. I look forward to hearing others comments.
Unless Raycore will stipulate that they only use low global warming potential (GWP) blowing agents for the foam, the high likelihood is that it's blown with HFC245fa, with over 100x CO2 GWP, which renders more damaging to the climate than a stick built code-min with crummy batts as cavity fill. Over the entire lifecycle of the house, it will NEVER make up the GWP deficit in energy savings, even if they were heating with a coal stove.
I've yet to find a PU-SIP/panel vendor who uses a low-GWP blowing agent, though there are a few spray-foam vendors using water-blown foam for some or all products, and some are probably moving over to Honeywell Solstice at some point.
Hi Dana, from what I have read, it is my understanding that the polyurethane is injected into the mold in a liquid state and cures. The studs are laying in the mold when the poly is poured. I am not an expert by any means, but have been researching the panels for a house I plan to build in Maine. They seem to be a better alternative to regular sips where you can get delamination. Anybody have any advice on this product. Pro's and Con's.
OK, so it's a liquid (it's also a liquid when sprayed)- the question still remains: What is the foaming agent?
Almost all slow-rise polyurethane-pours use HFC245fa too.
Aloha Energy makes a water-blown 1.8lb pour, but they are the only product line I know of using a low GWP agent in a closed-cell polyurethane pour.