80 Foam Spraying Continues

Well, I've found the part of housebuilding that I hate. Hate might be a little extreme, let's just say I dislike it ...a lot. In that Tyvek suit, sweating myself silly, even if the temp is 80. I don't start spraying until the airtemp reaches 80, which is usually about 9 a.m. By the time I get two cases (12 canisters) sprayed the temp is getting over 90. If the foam temp reaches 92 or 93 I need to be shutting down spraying because the foam will start "exploding" (my term), meaning it expands unpredictably creating big air bubbles, some of those air bubbles pop. It makes for a nasty finished apprearance and I suspect a severly compromised insulation capability.

The first couple of body suits I bought were the cheaper, polypropylene suits. While they breath better than the Tyvek suits, they just don't have the durability. Getting one to last more than one day is tough. The Tyvek suit I'm using is easily 2 weeks old now and still holding up just fine. It just doesn't breath at all, so it feels hotter when wearing it.

Tyvek Suit Tip: When you take it off turn it inside out and hang it up on a hanger. It will dry pretty quick.

Foam Results: I feel like I'm getting about 35% less yield than I should be getting. Or said another way, the foam is going only about 2/3 as far as it should. At this rate I will have to buy more foam to complete the roof. The advertised yield is 200 bd-ft per case (6 canisters). I calculate I'm only getting about 130-135 bd-ft per case. I talked to Soythane and they say that most people get more than the advertised yield, not less.

One possible explanation they suggest, is that since I'm spraying it on metal roofing, it takes extra foam to fill in the "ridges" that occur every 9" of width. I agree it takes extra foam to fill the ridges, but not 35% more foam. So, I drew a cross section out and calculated how much extra to fill up the ridge...4% extra. That's a far piece from 35%.

Soythane has asked me to mark off a known area on a flat surface and spray out one whole canister and measure the yield. I guess I'll do that tomorrow.

Out of my original order of 31 cases I have sprayed 23 and I'm just barely halfway through on the roof. If this yield problem continues it may have been cheaper to hire it sprayed.

Oh well.