Contractor Talk - Professional Construction and Remodeling Forum banner

1 - 15 of 15 Posts

·
Registered
Joined
·
8,573 Posts
I still don't like the idea of an enclised attic space. I wonder what the R value of the "under sheathing" insulation that they blew on the bottom of the roof deck and all over the rafters is.

To the best of my knowlede that would never fly here! Your attic would be damp and humid in the winter time. If the R value of that sprayed insulation wasn't superb you would have all sorts of ice damns. I didn't see any underlayment on that roof, under the tiles and the adhesive they were using wasnt a fully adhered system, and only placed under the tile meaning water can penetrate and rot the roof decking. I'm not even sure if there was any type of mechanically fastening, or just the adhesive.
 

·
Registered
Joined
·
10,471 Posts
Discussion Starter #3
Grumpy, coming from another source,'The foam insulation is installed by being sprayed directly up against the roof deck. The heat flow resistance of an R-20 of foam insulation is 95%. The insulation is brought down to the perimeter wall creating an airtight seal. No insulation is installed in the ceiling due to the fact that there is no heat gain in the attic. Passive air exchange takes place between the attic area and the living area or "conditioned space".'.
If you look a little closer the tiles were being stuck to felt and you are right that there were no mechanical fasteners.
The way that I see it is that they are depending on the unitised tile structure to stay put due to nearly sheer mass. Being stuck to the felt, I don't find particularly attractive. Now if that foam would stick to Grace I&WS we'd have us a whole new ballgame.
You're too young to not embrace the new tech. I remember flying back from Paris on the Concorde in '84 and the cabin LED was reading mach 1.3, I was thinking of my first flight in '59 in a DC-3 and how far we had come in such a short time.
 

·
Registered
Joined
·
8,573 Posts
I'm not embracing it only because it seems flawed in so many ways. It totally goes against the grain of conventional insulation/ventilation principals. Also it's too new and not proven yet.

Ok if there is some kind of air exchanger that takes the moist stagnant air from the attic and puts it back in the living space, that would deal with the moisture issue. If the foam insulation is r 20, that might helps with the ice damn issue, but I think R 20 is'nt enough to prevent an ice damn build up.

As you know ice damns forms when the exterior snow is melted from the bottom side by the interior heat. That is why people ventilation their attics, to release heat. Since there is no ventilation, the insulation has to work over time.

If I installed that roof, and was had the equipment on site I'd coat the entire roof deck with spf water proofing then the sprayed uerthane adhesive. That would be totally water proof.
 

·
Registered
Joined
·
10,471 Posts
Discussion Starter #5
Grumpy, This relates to MY zone. From what I have read, it can apply to all zones with varying installation factors.
You know me, there is only one company doing it in my area. I'm thinking that he needs competition.......aaaannnnddd aaawwwwaaayyyy wwweee go! It makes sense to me and I have all of the connections.
 

·
Registered
Joined
·
8,573 Posts
Just make sure you do a better job on the roof water proofing. Perhaps take my advice about the sprayed poly foam roofing BEFORE the tile. The SPF will be the actual water proofing and the tiel ontop woudl be the protection. Call Tom Hay at Preferred Roofing (Roofers?) in or near Clear Water.
 

·
Registered
Joined
·
174 Posts
Doesn't the foam tile adhesive stick to Grace Ice & Water Shield? I thought it did. I know polyeurathane expanding foam sealer does. We dont' have "glued down" tiles out here. All nailed. I thought that sprayed poly foam insualtion had to have a coating applied to make it waterproof. The roof foam does.
Jim
 

·
Registered
Joined
·
10,471 Posts
Discussion Starter #9
I was refering to the sprayed insulation, I have no thoughts of becoming a roofer down here. Too much competition. I'm always on the lookout for niche businesses, there is only one guy doing this and he's in another county.
 

·
Commercial Roofing
Joined
·
1,220 Posts
SPF can be used as a roofing system when used with an elastomeric coating for UV proection. Also, lighter weight foams are used for insulating houses. I did not watch the video, but I look to start into the SPF business within the next couple of years. I have spoken to a few in the business, and have been doing some research, but am far from an expert.

From what I understand the A side is the polyurethane and the b side is the blowing agent. Different blowing agents are supposed to produce different weight foams. The polyurethane, according to Mr. Thomas Hay, would be the strongest superglue you ever saw without the blowing agent. I heard that his company had multiple hurricanes go over 27 of their buildings and no wind damage was evident to any of them (aside from flying debris, I would assume).

I am hip to this stuff, and was even going to buy Mr. Tom's business and relocate him to Chicago, but somebody down there beat me too it. :(
 

·
Registered
Joined
·
10,471 Posts
Discussion Starter #11
Aaron, You pretty well understand the foam end, Part A is all the same and the part B can take you from 2-22# densities. Part A will stay sticky forever without the catalyst. Part B will air dry and has to be kept tightly sealed. Polyurethane components will also absorb water and alter the charateristics of the finished product when mixed.
As far as gluing things, I dont know of much that sticks any tighter. I was actually thinking of making some forms and using some high density stuff for rafter tiedowns on concrete tiebeams.
Getting away from the foam, you can buy it in all durometers and even get it hard enough to make sheetmetal forming dies.
I have some sites if you want to look into it further.
 

·
Registered
Joined
·
66 Posts
Teetor,
Check out www.ersystems.com Great people to do business with. Yearly schools for training, equipment & products. Get set up and if I need work done in Naples I'll call you rather than drag my equipment down there.

Crankshaft
 

·
Registered
Joined
·
10,471 Posts
Discussion Starter #13
Crankshaft, you travel all of the way down here for a roofing job? How much demand is there for this product/system? What are the profit margins? E-mail me if you are not comfortable posting this info.
 

·
Commercial Roofing
Joined
·
1,220 Posts
Teetor, I would like ALL the info I can get a hold of on the subject, Thanks.
 

·
Registered
Joined
·
10,471 Posts
Discussion Starter #15
This will get you started. Goldenwest is mostly low durometer casting resins and carry most anything that you might want for silicone molds. Adtech is pretty pricey aerospace stuff, avg. $150 gal. but worth every penny if that is what you need.

http://www.goldenwestmfg.com/
http://www.adtechplastics.com/
 
1 - 15 of 15 Posts
Top