How to Fix a Leaking Rooftop Vent Pipe | This Old House

This Old House general contractor Tom Silva shows how to create a watertight seal around a vent pipe. (See below for a shopping list and tools.)
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Shopping List for How to Fix a Leaking Rooftop Vent Pipe:
replacement rubber gasket [amzn.to/2NTqPXe], for installation over existing, leaking gasket
lap-seal caulk [amzn.to/2NTYobz]
Tools for How to Fix a Leaking Rooftop Vent Pipe:
pocketknife [amzn.to/34AgDZI]
caulk gun [amzn.to/2Lorz4S]
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How to Fix a Leaking Rooftop Vent Pipe | This Old House
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[@fabcraftsandmore]

Thank you! I thought I was going to have to replace the whole flashing boot unit. This saved me so much time. I had no idea these could become such an issue.

[@AlwaysONTHERISE247]

this is not the way to fix anything sir or miss, this is absolutely the worst way I have seen this repair done. plz don't take anything these guys do as correct... it will only cost you more to fix it correctly very soon after...

[@richardb9779]

Knew I could count on This Old House...Had a vent pipe get smashed by solar panels during hurricane Zippy(Zeta). Jagged edge tore rubber on pipe flashing. While I was repairing the pipe I noticed other pipe flashings had started to tear, probably like Tommy said...Sharp edges left on cut pipe. Thought I was going to have to change all my pipe flashing. All I have to do is go into attic and get pipe measurement and number of flashings. The rest is easy. Thanks Tommy...

[@3keelynrylee]

Had a customer with a similar issue and recommended using Through the Roof which is clear and he was able to do when wet! Through the Roof sticks beautifully to PVC and stretches up to 1000% so it won't crack like that silicone did!

[@KY_REDDYNESS]

You guys are heroes! 👍🏼

[@adam182r9]

This is an amazing video and tip. Thank you.

[@heroknaderi]

Wow quick and easy 👍

[@sajidbaig1593]

Great information!

[@manuelgonzalez3075]

You guys ROCK!!!

[@bdclongislandroofingco.8843]

Good video Tom.

[@Maxid1]

Yeah Bob, what were you thinking!? Silicone? It's all lap seal caulking these days, and ball bearings, Sheesh!

[@mikee33oo]

awesome! simple! i shoulda watched this before going to home depot lol

[@victormoralesred]

Thats cool.

[@Shickenjanksy]

Glad I found this. My roof is too steep for me to try and replace the whole thing by removing shingles.

[@ericwotton2046]

I always throw a second rubber gasket over the first one. I figure the top one will help the one below it from getting beat up vy the sun.

[@tabcan]

I like that ladder. That's the first one of it's type that I've seen.

[@Astromyxin]

It's called a chicken ladder.

[@nightfangs2910]

Used in Germany a lot permanently mounted

[@tkjazzer]

They never seem to talk about the roof safety equipment

[@truetalk5023]

A lead soil stack is the BEST way to go when having a new roof installed.Will never rust,root or fall apart. Plastic or rubber for a boot is junk. But I commonly see these rubber boots get caulked from their first day installed. Good video and I love your ladder.

[@kurtvonfricken6829]

If you go with a lead stack might as well go with a slate roof. All of the parts should fail at the same time in an ideal World.

[@1969CampEvans]

CORRECT

[@Simplexaero]

Rubber vs. lead is actually more related to climate. Rubber boots are used in more northern climates, while the lead pipe jacks are used in southern climates.

[@benjaminblack5888]

The squirrels love to chew the lead pipe jacks, the Bullet Boot is a 50 year warranted product. Also, the pvc stacks are supposed to be painted with a water based latex paint.

[@robertanello7649]

Where did you get the blue roof ladder shown in the video?

[@danielnapper1572]

Hey Rob great informative video . question when installing a new roof should i replace vent pipe gaskets ? I binge watch This Old House on Pluto TV channel 618 im from Toledo Ohio

[@Me-kt3gh]

Absolutely. When replacing the roof, every roof accessory should also be replaced. It’s the best time to do it and it only costs about $6 more per pipe versus doing a repair which can cost $150+ per pipe. Same with metal pipes, replace the flashing while the shingles are off and paint them with a rust resistant paint.

[@Smokey-mt6ye]

Excellent video thanks

[@khuramhussain7802]

I used 60% of my phone battery watching these videos 😂.

[@official13dvls_broknlnk_16]

This is the way

[@grey7603]

And 2% for "other proclivities".

[@jgt9338]

If the boot was painted white do you think it would last longer? I am about to do this job as a preventative maintenance as I do not have a leak at this time. My boots are about 10 years old and still good but I want to get ahead of the problem.

[@bigd1604]

Perma Boot is the only way to go! I have them on all of my vents.

[@brosskitchens]

What type of caulking was that again? I'm having an emergency roof vent pipe issue & I've gotta do just this on 4 vents before the sun goes down.

[@oneworld2642]

I think the leaking is above the pipe area or around the round metal plate.

[@davec.3198]

You know you have a hack roofer when they shingle below and over the bottom of the flashing. That does nothing but collect water. Personally, i would have installed that with the last layer of shingles underneath the flashing as well. Water runs right down the roof, right around the tube on the flashing and goes to the side. There is very little shingle under the middle of where the tube/boot is. I think he fixed the wrong problem. I think water is running down around the boot and getting under the shingle.

[@mcg8289]

I agree , shingiling over the bottom half of the boot is a rookie move.

[@SMCDisaster]

I love your channel but you should look into the “perma-boot”. They are amazing and last the life of the roofing.

[@TheGuohua]

Whenever Tommy runs a bead of caulk he always refers to it as "nice" and/or "thick". I think it's a legal requirement when you work for This Old House.

[@edsoncastillo96]

Do you have to put a cap on top of the pvc ?

[@tannerfrancisco8759]

No, you want it wide open. It just goes to your sewer lines so any water that goes down it just goes into the sewer.

[@illchuckncaggie]

Do the vent pipes need a cover on top of them to prevent water from getting inside?

[@jimmypautz]

This is why I put lead pipe flashing on my roof...will last longer than the shingles. I also shingled it the right way...not with a hole in the shingle.

[@ralphneighbors3752]

Unless the squirrels chew up the lead, like they did mine.

[@jimmypautz]

@@ralphneighbors3752 I don't get squirrels. I've had lead flashing before and I put new lead flashing when I re-roofed in July.

[@beland21]

If I install the flange just to make sure that's the problem and not glue it down will there still be water?

[@mikedeetch7383]

Use a lead flashing, they don't dry rot or need caulking

[@ralphneighbors3752]

Yeah, I had that idea, too and the damned squirrels chewed them up. Hope they got brain damage.

[@MRrwmac]

Could you please tell us more about that type sealant he used from the tube or one that is as good we can get from Lowes or Home Depot? Thanks.

[@MPIronmanJC]

Long time ago I know, but in case anyone else was wondering it is Geocel 4500 Roof Bonding Sealant

[@Phil-D83]

MRrwmac dymonic 100 stuff works well. Don't get it on your hands.

[@RafaelGarcia-qt9eq]

What about Chem-Link M1? Can that be used instead of the Geo 4500?

[@MRrwmac]

Yes I had seen this one but I believe there is a leak through the flashing. Is there another video by Tom on how to fix/replace the flashing around a roof vent tube?

[@Phil-D83]

MRrwmac use dymonic 100

[@tonkatoytruck]

They actually make replacement sleeves that you can acquire at your local home center. It slides over in the same manner but is a little more heavy duty and it covers much more of the vent pipe.

[@miguelsalgado9940]

tonkatoytruck its a perma boot

[@teemingjoker3790]

Wouldn't you end up having the same problem later down the road with the new one you just put over top? I saw a product at Home Depot called "Perma-Boot" didn't know if you knew anything about that but apparently it has a life-time warranty. They have no rubber gasket involved, so assuming no fail ever.

[@kurtvonfricken6829]

The idea is to buy time so when you replace the roof you do it all together.

[@Giggiyygoo]

I always wondered why no one has invented a wide high-grade rubber band that would just go over top of the old cracked seal. Time to go on shark tank.

[@deadlymig123]

Giggitygoo we do lead stacks that go over the pipe so you never have to replace it. Rubber is no good

[@javiergomez8711]

Use 3m window urethane it will keep the house together

[@Sarcastic-weirdo2043]

0.28 if it gets a crack, waters gonna get in there . (Customer) oooooooougghhhhhhhh..........

[@TheCameraMonkey2]

Where can I find the rubber gasket?! Everywhere I've looked in the SLC area doesn't carry those! HELP!

[@shawnr771]

I know this is 4 years late. Just buy the whole pipe flashing and cut the metal part off with a razor knife.

[@losll]

How would you repair the rotten sheathing around the pipe from the attic?

[@wanelly]

Scared of heights? I feel you. Unfortunately, you can't. I tried it and it didn't work. Go to the roof.

[@ms.ladietoyou8672]

omg😮 I am so scared for Tom being on the roof without protection. my knees are trembling

[@Huero805]

where can I find that flange?? home depot , lowes, hd supply don't have ive been to numerous hardware stores no one has it?? on line? website?

[@shezie9525]

Im sure all of those listed will have them.

[@jbohardy]

Help!! I did this verbatim, and I still have leaks. What should I do next?? do you think it is leaking at flashing,nails, shingles????

[@mrcoz1764]

If you installed a new gasket and it still leaks you either damaged the new one installing it,,,or your problem is under the shingles

[@OKFrax-ys2op]

Why not cut the old one & remove it, than install the new one. The old one will fail on the bottom, won't it?

[@twobeer3316]

I was thinking the same thing. The old one looked like it just slid on, why not remove it ?

[@stevenschoenfeld7405]

Probably because it comes very well adhered to the metal base. It wouldn't be easy and whatever adhesive they use to attach the old flange to the metal base would also have to be removed for the caulking.

[@jewfrogabe19]

fucking Siliccone Bob!?! I cant even.

[@TheCalichick619]

Could this cause sewer smell in home ? I keep getting a sewer smell in home I’ve already flushed stuff down all drains cleaned out p traps etc do I need to check roof ?

[@kurtvonfricken6829]

Probably not. What is leaking here is the seal between the outside of the roof and inside. I doubt they leak much air.

[@davec.3198]

Likely not the issue....i did have hornets make a nest in one of mine though. It was almost plugging it.

[@Moonless6491]

Could be a bad wax seal under the toilet leaking air from the drain.

[@jasedaniels4412]

What if you have a metal roof?

[@scottsmit1115]

anyone used the Flex Seal to fix the roof leak? Pro and Con please

[@psmithphil]

You might want to see this video: kzbin.info/www/bejne/g6fPlZ2OfZuWhtE

[@Astromyxin]

Never use flex seal to fix anything. That product is garbage. Totally useless.

[@markyochum9753]

Scott Smit I tried flex seal. Had heavy downpour. Roof leaks. 😞

[@mistercrockett]

Flex seal works but I only use it an an extra layer of sealant, not my primary sealer

[@zach16]

@@mistercrockett Same here. You also probably will need several coats to build up. Good in a pinch

[@ScienceBitch123]

Why not remove the old gasket too? Looks like a sloppy shortcut

[@blacklimosmatter2023]

"THE BIGGER THE BLOB THE BETTER THE JOB" LMFAO!!!!!!

[@steamsteam6607]

I know it's a sanitary pipe but really isn't there something covering it normally to prevent leaves and bugs and whatever else from getting in? I guess water isn't an issue.

[@iLikeC00kieDough]

Nope. In fact, if you live in a northern climate, having something covering the top can cause ice to build up and block it off

[@trevorweldon454]

Anybody gonna mention the rip in the new one?

[@user-on7yi4uf8t]

How about rain going in the pipe?

[@johnglue1744]

Doesn’t matter. That is the exhaust pipe for your toilet flushing to allow sewage gas to escape your house safely.

[@user-on7yi4uf8t]

@@johnglue1744 Thank you!

[@stephensnell5707]

@@johnglue1744 you mean Sewer Gas

[@eschrader]

So if I get gasketsmy roof lifetime warranty I'll have 7

[@robnai3372]

When in doubt, use more silicone!!

[@davec.3198]

Says every horrible roofer.

[@CoolManDudeRN]

That'll be $3000 sir.

[@shadowblack1987]

In europe our roofs last 30-50 years before light maintenance is needed. They also cost less than american shingle roofs 🤣

[@user-nh3gu1ge3d]

Well that's clearly bs. Who told you this? And what roof types are you referring to? Tile or metal vs shingle? All of those types of roof exist in the US, they are just more expensive so fewer people choose them. It's not like Europe has some magical roof property that the US doesn't have.... Ridiculous.

[@shadowblack1987]

@@user-nh3gu1ge3d BS? Literally just had a new roof put on my US home. 3 times the cost of the one of my german house (both have standard metal roofs, not that shingle garbage, which isn't that much 'cheaper' than metal). Both houses have similar sq/ft. So next time you want to try and sound smart, better keep quiet. Also since i'm building new, same BS for windows and doors. Double the price than Canada, triple the price than Europe. Country of thieves. Go educate yourself kiddo, only thing ridiculous is you and American prices which are made up of 'whatever we want to charge'. Also this has NOTHING to do with COVID. I compared last year and this year for US, Canada and Europe.

[@brandiigiibson]

What about a metal roof?

[@RonRay]

Why not remove the old flange? That way, the new one would make a more perfect fit.... or seems so.

[@optimistichorizon]

My first thought as well. Likely job security.

[@nyw11]

When you replace the whole flashing, you're supposed to replace the shingles around the flashing too. If the roof is older or the shingles are discontinued, matching them might be impossible. The repair shown lets you fix the issue without worrying about the shingles. Once you replace the roof in another 10 years, you can replace the flashing.

[@1969CampEvans]

The roofer cut corners or the home owner failed to inspect the job before the roofer was paid.

[@Astromyxin]

@nyw11 No, that is not correct. There is no need to replace the shingles around a collar if you have not damaged them attempting to remove the collar.

[@cobaltpica]

Isn’t that way too much caulking?

[@Prairiedrifter1]

12 yeahrs

[@TheFreeLandersGuide]

As a retired roofer, this is a hack job on fixing the pipe collar.

[@glorygloryhallelujah]

2004 was the worst year in baseball

[@echt114]

If the tear was allowing water to enter, why not just seal that point on the existing flange with caulk/silicone? Shouldn't that work?

[@tabcan]

The sun degrades the rubber over time and it becomes brittle, leading to cracks and failures. He probably could have poked his finger right through it. A new rubber flange isn't expensive and should be good for another 10 years.

[@Josh.AdamOfficial]

ouch when he took that knife to that plastic that way! sounds like that make me cringe for some reason.

[@king49334]

Silicone it

[@Bonjam1n]

1,000 th like

[@Spartan1234ish]

It's unbelievable how people talk and act like taking the lazy way of fixing something is better. To replace that flange and maybe a bundle of shingles wouldn't cost much. So what you charge them less for material doing it the lazy way but charging them a mint for labor. Seriously unprofessional.

[@kurtvonfricken6829]

paulpaulpaulpaul The idea is to stop the leak. The theory being when the roof is replaced you replace everything. I did this to all 3 of my waste stacks when one started leaking after 18 years. Now bone dry. When the roof needs replacing in the next 10 years or so I will replace everything with higher quality components. I consider it a temporary but viable solution.

[@RayBk1]

😂

[@nocomment7144]

Wonder how Norm Abram's would feel about the utter disregard for use of safety netting, harnesses & helmets

[@RonDovev]

ו

[@centauris10]

I fell off the roof

[@Imf44]

I WANT TO EAT THAT SILICON, LOOKS SO GOOD

[@stephensnell1379]

⚠️NOT ADVISABLE AT ALL ⚠️

[@michaelfreeman8458]

I trust this is a legit fix, but the thumb nail picture makes it look bush-league. "Handy-man with caulk gun"

[@vido4x4]

Tom made me nervous watching him on that roof with no anchoring gear

[@MrNorthstar50]

Why didn't he address the pvc pipe not being painted to block UV from destroying the pipe , it is code in Texas.

[@Sam-fj1ug]

Perma Boots Better...….

[@oscarmuffin4322]

Really? American think 12 years is a long time for a roof to stay intact? My roof has been up for 200 years with only a few boards needing replacing. All structural beams are still good as new. Just shows you that stuff isn't made to last anymore.

[@iLikeC00kieDough]

What is your roofing material made of?

[@CougarLand]

Another example of a roof vent that could easily and permanently be fixed by using Perma-Boot. Just sayin.

[@shawnr771]

Perma boot costs 20.00 dollars each. I have installed many of them. They do not work on certain steep roofs. This is much easier, cheaper and will generally last the lifetime of the roof. As a homeowner, if possible check your roof once a year for problems. High winds, storm damage, rodents(such as squirrels), also since the advent of using OSB board as decking, nails backing out seems to be a more common problem.

[@Africanfrogs]

Must have been a terrible job. Most roofs should not leak until they need replacing 25-40 years For a good quality shingle roof, must have been the wrong caulking or something if they all failed

[@larrymiller1626]

Tom is definitely a master in his work. But roofing isn’t it. That old rubber on that old boot that is exposed will be cracked before long. Might as well change the boot out. We tell our clients on new roof replacements every 5 years the boots need replaced.

[@themechanic4222]

But if contractors knows the flange will get bad over years why they don’t add silicon from the beginning ? Cheaters

[@patrickm.parisou8328]

This is so much of a joke that I can’t leave rant. This man has no business being on tv let alone being a contractor. TOH should be ashamed.

[@junkstough6622]

Is Tom really up there without a harness? Yikes

[@mr.wizeguy8995]

So this boot is made in US. and barely last 10 year and you are so proud of everything that is made in murica :)

[@leonk.1031]

Rollo Lawson tires from Germany are probably better than tires made in USA or China.

[@johndough23]

Planned obsolescence is the entire economy. They teach this in Engineering schools. Biggest scam going. The waste created is mind boggling. They should require all consumer products to have a good till date +/- 6 mos to the exact date this product will fail on the label. Here's the premier video about this topic...kzbin.info/www/bejne/sJXLaJKGdp16kLc

[@jasonmorehouse3756]

S B you are a moron to think a +/- 6 mo exact fail date could be applied.

[@johndough23]

re: Jason Moronhouse Which indicates you know nothing about the topic. THEY ALREADY build stuff to fail by a date certain. GET IT? That's why your car falls apart as soon as your last payment is mailed. This is juvenile simple stuff sir.

[@iLikeC00kieDough]

Stephen Brown if your car is falling apart after your warranty, you aren’t maintaining it properly

[@MorrisonZ1488]

Caulk is his answer to everything. Amateur

[@HarveyWallbanger-ho2cq]

Putting rubber on a roof is just foolishness

[@AlwaysONTHERISE247]

so this is maybe the worst way I have ever seen this particular repair done and I have been a roofing contractor for 23yrs if you want to learn how to do repairs, do not watch videos from companies or shows like these.... they're ignorant salesmen and nothing more!