Roofing discussion!!!

[Frankenkubota]

When I put in a flange in a sink, I use 100% silicone caulk/sealant. It's the only thing I use 100% silicone for. Also, keep in mind that if you ever have to re-caulk something with 100% silicone, all the old stuff has to be removed mechanically (i.e. sandpaper) it does not stick to itself. I do not reuse anything that's had silicone caulk on it unless I have to.

When you put the flange in, once the sealant is in contact with both the flange and sink, twist it a little to be sure the caulk does not have any gaps in it. (just like you do with PVC pipe fittings)

many thanks, off to buy silicone

 

[briansanders]

attach is one example, I like the length from the exhaust to the roof on this one but see your hardware store look at your options as long as they have a back draft damper, a screen so nothings goes in and a decent pipe diameter. (at least 4'' diameter) Use hard line pipe and not flex pipe as flex increase resistance.

I don't know your house configuration here but if its a finish house the roof might be easier to install you simply have to cut the hole through the sealing to the addict then through the roof and shingles and you just slip that in. for the wall you might have to deal with fitting it under the siding which can be lots of work … but you also could bring it to the addict and pipe it to a gable which could be easier then the wall … but again the major components for resistance are diameter, distance and corners. Resistance = less airflow...
View attachment 707866

This option is too complicated. You can do it much faster and easier, as the guys advised.

 

[EddieWalker]

When I put in a flange in a sink, I use 100% silicone caulk/sealant. It's the only thing I use 100% silicone for. Also, keep in mind that if you ever have to re-caulk something with 100% silicone, all the old stuff has to be removed mechanically (i.e. sandpaper) it does not stick to itself. I do not reuse anything that's had silicone caulk on it unless I have to.

When you put the flange in, once the sealant is in contact with both the flange and sink, twist it a little to be sure the caulk does not have any gaps in it. (just like you do with PVC pipe fittings)

I use 100% clear silicone. I buy the small, squeeze tube for this. I can usually do several sinks from the one tube, and its something that I keep in my truck at all times. I put it on the sink, around the hole, pretty thick. Then after it's all tightened down, I wipe away the excess with my finger, then a dry paper towel to get all of it. Sometimes this takes a little effort since it sticks to everything and it can get messy if you are not careful.

 

[Frankenkubota]

I use 100% clear silicone. I buy the small, squeeze tube for this. I can usually do several sinks from the one tube, and its something that I keep in my truck at all times. I put it on the sink, around the hole, pretty thick. Then after it's all tightened down, I wipe away the excess with my finger, then a dry paper towel to get all of it. Sometimes this takes a little effort since it sticks to everything and it can get messy if you are not careful.

yea....i been trying. 8 hours yesterday, on and off, 1 sink might be done, not sure....i never trust plumbing...especially mine.

i bought the tube of clear silicone and did exactly what you mentioned, which is the same as the instructions.

my problem is, after you put the silicone on the underside of the flange and set it in the hole at the bottom of the sink, you are not supposed to turn it. They tell you to pull it directly down while tightening the big nut.

Problem there is, you must first screw on the tail piece that has very fine threads. You got one hand under the sink trying to start these "watch maker" threads while the other hand is on topside, trying to keep the flange from moving. Your chin is on the countertop and you can't see a thing.

Impossible....for me. A friend happened to stop so i got him to hold the flange down while i attached the tail piece......leaker!

I thought it was me being my normal self but i did find a plumbing forum where many people were having the same problem. The hole at the bottom of the porcelain sink is a 45 degree bevel and the flange is a sharp edged piece of metal. Both just want to leak.

I understand that sinks vary and the faucet flange has to be universal but.....imho.....it's a lousy design, one of the plumber forum pros said the same.

And yes, silicone is nasty once it starts to spread itself around.

thx all....keep trying...hate plumbing

 

[rScotty]

The trick with silicon for sealing anywhere is to put on a bead of silicone and let the surface of the silicone just sit there and cure for awhile - usually 30 minutes to an hour - until you can touch it and it feels not sticky but is more like putty or modeling clay and not so runny anymore. Then it's OK to do final assembly and tightening things down.

When I do that, the silicone works really well. Otherwise I find that it is just as likely to be a leaker and messy too.

The same technique works for gaskets on mechanical projects. For those, let the silicone start to cure even longer before assembly. Sometimes if I get a good thin even coat of silicon gasket sealer I'll let it almost cure completely before assembly. That's when it works best.

BTW, I often use the squeeze tube of Permatex "gasket maker" for plumbing projects instead of the construction caulking tubes. It's a bit thicker and stickier.

 

[EddieWalker]

Letting it cure makes me nervous. I want it to stick to everything, fill every void and when cured, become a solid barrier. I understand your thinking, but will never do it that way myself.

 

[Frankenkubota]

The trick with silicon for sealing anywhere is to put on a bead of silicone and let the surface of the silicone just sit there and cure for awhile - usually 30 minutes to an hour - until you can touch it and it feels not sticky but is more like putty or modeling clay and not so runny anymore. Then it's OK to do final assembly and tightening things down.

When I do that, the silicone works really well. Otherwise I find that it is just as likely to be a leaker and messy too.

The same technique works for gaskets on mechanical projects. For those, let the silicone start to cure even longer before assembly. Sometimes if I get a good thin even coat of silicon gasket sealer I'll let it almost cure completely before assembly. That's when it works best.

BTW, I often use the squeeze tube of Permatex "gasket maker" for plumbing projects instead of the construction caulking tubes. It's a bit thicker and stickier.

thx for that and that's pretty much what i did.

i didn't realize how firm the silicone was once it hardened so i let it set up a little first.

as of this morning i have 3 sinks that do not leak.....yet.

 

[zozomike]

In my region of poor people, and lots of metal roofing, overlays are pretty common. The best practice way to do that is to first put down underlayment, either felt or synthetic, (the unspoken part in all the above being that the existing shingles may have leaks, so underlayment does matter) then run 1x or 2x " purlins perpendicular to the slope. sometimes foam is laid between the purlins. Its advantage being full support under the metal. On this the metal is screwed to the "purlins".