# Proper Way To Repair Caulk?



## dutchman

Three of us were standing around this morning dreaming about being able to get the TT dewinterized now that it's getting a little warmer. The question came up about the proper way to repair caulk seams such as those around the vents, AC, etc. on the roof that had cracked open over the winter.

We were in agreement that Dicor caulking should be used on the rubber roof.

The options seemed to be: (1) clean out all the old caulk then apply new beads around the opening, (2) just caulk over the old stuff to seal up the crack, and (3) clean out the loose stuff only and then caulk over the open seams.

What's your opinion(s) of the best fix? My vote goes to number 3.


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## skippershe

I would say number 3 as well









Great question to ask!

And the correct answer is..........?


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## Northern Wind

I have always cleaned out the old stuff and replaced with new, my feeling is if the old stuff is no good why just cover it up and take a chance of it not sealing and breaking away.
Steve


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## 3LEES

I agree with Steve. Since the old caulk has failed (cracked), then all caulking in that area is suspect.

I would remove the failed caulk and recaulk.

Dan


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## TLC+3

We bought our Outback used. I told the service manager at the dealer that I would most likely do all my maintenance and repairs myself since the unit was used and the dealership was so far away from my house. I asked him lots of questions, including this one. He said to always remove the all of the old caulk, not just the failed portion. They get lots of units in for service with leaks that the owner tried to fix by simply adding more caulk on top of the old stuff. Based on that info, my vote is to take the time to remove all the old material.


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## skippershe

Alrighty then!
Remove and replace is the way to go








Makes sense to me


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## Oregon_Camper

Clean out the old....reapply the new.


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## camping479

I only remove what is loose, clean it up with a rag dampened with naptha (fast drying version of mineral spirits) and then apply fresh sealant.

I know you're not supposed to use solvents on the rubber roof but naptha is a mild solvent and flashes very quickly. I'm also only dampening a rag with it and using it mostly on the sealant so it's not being heavily applied to the membrane itself. Besides it does an unbelievable job cleaning.

Mike


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## CamperAndy

You should only remove what is loose, clean well then apply new bead but only if it is cracked or missing.

Attempts to remove all the Dicor caulk will result in damage to the rubber roof membrane.


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## camping479

Good point Andy, the dicor is very tenacious and would most likely result in damage to the membrane if you tried to remove it all.

Also if you don't clean the old sealant before applying the new, the new sealant won't stick properly.

Mike


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## countrygirl

How do you get the old caulk off? What brand of caulk do you use on the sides around the lights and windows?


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## MaeJae

CamperAndy said:


> You should only remove what is loose, clean well then apply new bead but only if it is cracked or missing.
> 
> Attempts to remove all the Dicor caulk will result in damage to the rubber roof membrane.


I agree with removing only the loose stuff...
Clean any remaining calk and surrounding
area to ensure that the new calk will stick properly.









MaeJae


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## Mgonzo2u

countrygirl said:


> How do you get the old caulk off? What brand of caulk do you use on the sides around the lights and windows?


How do you get the caulk off is the first and foremost question needing a good answer. Then of course, what brand do you use to replace the old is a must have.

Anyone?

Andy?


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## HootBob

camping479 said:


> I only remove what is loose, clean it up with a rag dampened with naptha (fast drying version of mineral spirits) and then apply fresh sealant.
> 
> I know you're not supposed to use solvents on the rubber roof but naptha is a mild solvent and flashes very quickly. I'm also only dampening a rag with it and using it mostly on the sealant so it's not being heavily applied to the membrane itself. Besides it does an unbelievable job cleaning.
> 
> Mike


Ditto Mike
I used the same thing to clean it up a bit(Best part we don't have to buy that stuff







)

Don


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## Thor

Careful using naptha. This is not the nicest stuff.

I called my dealer and as them the question. Here is the answer

They remove all the loose stuff and as much as possible without damaging the roof
They clean the remaining caulking with a brillo pad (same used for washing dishes)
Really old caulking with maybe use a cleaner to clean the caulking
Re-caulk

They cautioned me over using solvents because they may adversely effect the rubber membrane (ie "dry it out" which may lead to cracking in later years)

Great question and thread.

Thor


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## CamperAndy

Mgonzo2u said:


> How do you get the old caulk off? What brand of caulk do you use on the sides around the lights and windows?


How do you get the caulk off is the first and foremost question needing a good answer. Then of course, what brand do you use to replace the old is a must have.

Anyone?

Andy?
[/quote]

The roof is easy, Hot soapy water with a soft brush to clean and Dicor self leveling caulk as the sealant. If it is really thick or been patched a couple of time use a plastic scraper to remove the bulk but do not attempt to get it down all the way to the rubber roof.

The side lights are a different matter. Silicone caulk was used and it is a bugger to remove or even clean up. For these locations I prefer to use a 100% latex Caulk but it will require regular attention. If you just want to patch a thin spot on the existing caulk you can clean it again with hot soapy water and then use a thin spread of 100% clear silicone caulk.

The Windows and doors are sealed with Butyl tape and should not be caulked. If they are leaking the window or door should be removed and the old Butyl removed and a fresh seam laid down and the door or window re installed.


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## Mgonzo2u

Thank you sir for your thoroughness.


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## aplvlykat

I pretty much agree with Andy, be real careful removing the Dicor on the roof. As far as around the lights I would also put some new putty tape under the light fixtures then seal with silicon. It seems like they use to do it this way years ago with minimal problems but to save a buck and time they cut back on this step. Kirk


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## Mgonzo2u

Got up on the OB roof Saturday to do some cracked (sealant) seam maintenance for the first time in about 3 1/3 years of owning the OB. There was work to be done but it wasn't bad, purely a pre-maintenance issue.

I thoroughly cleaned and dried the affected areas with plain water and a towel (while not removing any existing caulk). I let the nice sunny day do its thing to dry those areas even further and then I applied some Dicor Self Leveling Rubber Roof Sealant and it was a done deal.

Not fun stuff but stuff that needs to be done.

Get up there and check your seams folks. Time spent doing pre-maintenance will save you big $$$ down the road.


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## mike elliott

what is dicor caulk is it a brand or a certain type of caulking?


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## 3LEES

bcdude said:


> what is dicor caulk is it a brand or a certain type of caulking?


This is what it looks like:










I buy it at my local RV dealer.


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