Sealant Application Questions

[JaMa]

I have been working for the last week removing old sealant and tape. In some cases the sealant is over 3/8 inch thick and extends almost 2 inches beyond the fixtures. I have applied new Eternabond tape and am almost done removing the old sealant. I am going to apply Sikaflex 219 sealant which I have not used before. I am quite familiar with similar 3M products but with bedding applications rather than as a top sealant as on the RV's.

So after all that, my questions are: What thickness of sealant should be applied and how far from the fixtures should the sealant be applied to guarantee a good bond? I am trying to strike a balance between how long the sealant will hold up for and ease of removal for the next person.

[kketterling]

Based on your information I'm assuming your working on the roof. I've had great luck using Dicor self leveling. When I applied the sealant I overlapped the seam being sealed by about a 1/2" each side. Sealant once it leveled was about a 1/4" thick. You can always add more to the thickness after first pass has set up some. Is the Sikaflex self leveling?

[BraveWrigley]

Eternabond Tape does not require a final caulk seal, rather roll in the tape and make sure it is stuck to surface and you should be fine .... I use a roller or hand/fingers and really pay attention to the edges ..... I also make sure the surface is super clean and prepared before apply the Eternabond .... If the surface is prepared with Eternabond Clean tape it is lmost impossible to remove:

https://www.bigrocksupply.com/store/...ernaClean.aspx

[MSHappyCampers]

Be absolutely SURE the sealant you plan to use is designed for RV use and does not contain silicone! I would use the Dicor 502LSW self-leveling sealant.

I would put a small bead of sealant around the edges of the EternaBond tape after application.

Good luck, happy trails, and God bless!

[Forkyfork]

Eternabond is not compatible with silkaflex, it will not stick to it. I would use dicor.

Edited to add, I contacted Eternabond about using the cleaner on fiberglass. They said to use denatured alcohol.

[BraveWrigley]

Originally Posted by Forkyfork

Eternabond is not compatible with silkaflex, it will not stick to it. I would use dicor.

Edited to add, I contacted Eternabond about using the cleaner on fiberglass. They said to use denatured alcohol.

Eternabond is the seal, you don't need to caulk or add anything to the Eternabond repair - nor should Eternabond be installed over any Sealant, sikaflex, dicor, urethane caulk or any type of Caulk / Sealant .....

If you absolutely want to make sure Eternabond is permanent, clean, clean and clean again - make sure you have a clean surface with no residue from the cleaner remaining ..... then prime the substrate / surface with Eternabond Primer https://www.bigrocksupply.com/EternaPrime.html and I guarantee when done per manufacturer specs and the piece of Eternabond Tape is firmly rubbed in, the repair will last a long time .... No caulk or Sealant needed at edges of the tape patch ....

Areas that Eternabond Repairs work well on is long joints such as were roof meets the sidwalls / front rear walls or where you have a flange that the Eternabond can lap over or any stress related crack ....

if sealing luggage supports or antennas then set projection in a bedding of Sealant - press projection into Sealant - secure projection with screws and feather edges of Sealant, as required so as to avoid and water dam areas - Reason some seals fail is there is movement between projection and roof so make sure projection is stable or the edge of the Sealant was not feathered and water got under Sealant ....

If you need to secure something and you don't have good mechanical holding power but have an OK surface to mount to consider a Structural Sealant like M1 - It will hold steel decking to bar joists under hurricane conditions http://chemlink.com/m-1 so it will hold that vent cover on that won't stay on due to stripped screws / threads, if applied correctly and cured which does not take long.

[bobcovey]

Jack,

I've used 219 in non-RV applications and it is a quality product. However, I don't see anything on the Sikaflex website that says that 219 is a self-leveling top sealant. It is a very flexible GAP sealant for sealing two surfaces together where movement is expected. I couldn't find an application note or reference that says it is intended to flow out and seal lap joints from the TOP.
Like others have said, I'd avoid this product in favor of Dicor, especially given that you are using Eternabond and want the two to stick together.

Cheers,

[Forkyfork]

Originally Posted by BraveWrigley

Eternabond is the seal, you don't need to caulk or add anything to the Eternabond repair - nor should Eternabond be installed over any Sealant, sikaflex, dicor, urethane caulk or any type of Caulk / Sealant .....

If you absolutely want to make sure Eternabond is permanent, clean, clean and clean again - make sure you have a clean surface with no residue from the cleaner remaining ..... then prime the substrate / surface with Eternabond Primer https://www.bigrocksupply.com/EternaPrime.html and I guarantee when done per manufacturer specs and the piece of Eternabond Tape is firmly rubbed in, the repair will last a long time .... No caulk or Sealant needed at edges of the tape patch ....

Areas that Eternabond Repairs work well on is long joints such as were roof meets the sidwalls / front rear walls or where you have a flange that the Eternabond can lap over or any stress related crack ....

if sealing luggage supports or antennas then set projection in a bedding of Sealant - press projection into Sealant - secure projection with screws and feather edges of Sealant, as required so as to avoid and water dam areas - Reason some seals fail is there is movement between projection and roof so make sure projection is stable or the edge of the Sealant was not feathered and water got under Sealant ....

If you need to secure something and you don't have good mechanical holding power but have an OK surface to mount to consider a Structural Sealant like M1 - It will hold steel decking to bar joists under hurricane conditions http://chemlink.com/m-1 so it will hold that vent cover on that won't stay on due to stripped screws / threads, if applied correctly and cured which does not take long.

I dont want anything on my roof that doesn't work together. You never know when you might be putting a piece of eternabond over previous sealant and yes you can and yes its done often. Plus I HATE silicone. Personal opinion I realize. Long standing hate over the years of owning RVs, boats and older houses. Previous owners always use it and it always fails.

The primer is not for fiberglass roofs. Verified by contacting Eternabond directly. Use denatured alcohol on fiberglass. If you want I can repost their email. Not feeling like looking for it ATM.

[BraveWrigley]

Originally Posted by Forkyfork

I dont want anything on my roof that doesn't work together. You never know when you might be putting a piece of eternabond over previous sealant and yes you can and yes its done often. Plus I HATE silicone. Personal opinion I realize. Long standing hate over the years of owning RVs, boats and older houses. Previous owners always use it and it always fails.

The primer is not for fiberglass roofs. Verified by contacting Eternabond directly. Use denatured alcohol on fiberglass. If you want I can repost their email. Not feeling like looking for it ATM.

When you contacted Eternabond it was about cleaning the roof, not priming .... Yes you can use denatured alcohol for cleaning, agree .... You can also use water to clean but water will not serve as a Primer, right?

I respectfully disagree on Primer and your take as Primer can be used on Fiberglass Roofs and advisable when there is oxidation and/or surface is slightly pitted or rough ..... The Primer bonds to the surface by coalescing (come together to form a solid mass) all loose particles into a solid platform for the tape to adhere to .....

As for incompatible materials on the roof so long as they are not bonded to each other they should not effect each other ....

Agree, Silicone is almost useless, it can't even stick to itself!

[Forkyfork]

My question to Eternabond.

I have a fiberglass winnebago roof and find info about cleaning and prep products for rubber roofs including your primer and cleaners. What is recommended to use to clean or prep a 13 yr oxidized fiberglass roof. Also, can the eterna caulk be used on the gelcoat wall seams above the lower trim and around windows, or is there a more suitable product?

Their response...take it FWIW.

Suggestions for cleaning an oxidized roof would be IPA (alcohol) or denature IPA. EternaCaulk can be used of gelcoat with no issues.

Regards,

Rayfield Johnson
Field Tech Service Manager – EternaBond Products

We used dawn to pre clean the roof and denatured alcohol to prep the areas it was being stuck to.

[BraveWrigley]

Originally Posted by Forkyfork

My question to Eternabond.

I have a fiberglass winnebago roof and find info about cleaning and prep products for rubber roofs including your primer and cleaners. What is recommended to use to clean or prep a 13 yr oxidized fiberglass roof. Also, can the eterna caulk be used on the gelcoat wall seams above the lower trim and around windows, or is there a more suitable product?

Their response...take it FWIW.

Suggestions for cleaning an oxidized roof would be IPA (alcohol) or denature IPA. EternaCaulk can be used of gelcoat with no issues.

Regards,

Rayfield Johnson
Field Tech Service Manager – EternaBond Products

We used dawn to pre clean the roof and denatured alcohol to prep the areas it was being stuck to.

Agree use dawn / water / scrub brushes and whatever cleaners you want so long as they don't harm the surface and leave no residue .... Leave no residue is key .....

All I am saying that as a Professional Roofer, 42 years, and a Roofing Contractor for 36 years we were responsible for the leak as soon as our ladder dropped so we want to make darn sure the repair holds and we found Eternabond Primer indispensable for making sure the tape stuck like it was suppose to!

[Forkyfork]

Originally Posted by BraveWrigley

Agree use dawn / water / scrub brushes and whatever cleaners you want so long as they don't harm the surface and leave no residue .... Leave no residue is key .....

All I am saying that as a Professional Roofer, 42 years, and a Roofing Contractor for 36 years we were responsible for the leak as soon as our ladder dropped so we want to make darn sure the repair holds and we found Eternabond Primer indispensable for making sure the tape stuck like it was suppose to!

I understand where you are coming from. Im all about knowledge gained from experience, but I noticed on their primer it never mentioned fiberglass....because its not for fiberglass...according to the manufacturer.

And Im sure you mean roofs as in house roofs. An interesting related story. We had rolled linoleum put through the entire house. It was a product they had never used and required particular application due to compatibility. The installer that has been installing floors for 25 years and the company they worked for decided that what they use (which is an excellent product) would be fine. It wasn't, fortunately they didn't get the whole house done before finding out why not to use that awesome product and only had to redo one room.

[USCGMech]

I plan on resealing my roof also, which Eternabond tape is for Motorhome with fiberglass roof?

[BraveWrigley]

Originally Posted by USCGMech

I plan on resealing my roof also, which Eternabond tape is for Motorhome with fiberglass roof?

I have a fiberglass roof and used white 4" Eternabond for some spot repairs .... and also had a couple spots I used some urethane based Sealant called Boss .... Balance of my roof is fine but next year I'll probably Coat with an acrylic of some type ....

If you plan on sealing the Side and End Joints and Projections with Eternabond and plan on coating Entire Roof with some type of acrylic (recommend acrylic for fiberglass) like kool seal https://www.koolseal.com/product/rv-...m-elastomeric/ you may want to consider Eternabond Web Seal as it will accept the coating and you won't have an adhesion concern, at least on the flat areas of the roof .... You certainly can use White / Black or whatever color size Eternabond on the sides that you deem best for the task - but if coating is applied over normal Eternabond, coating may peel here is a link to their website and all sorts of info ....

https://www.eternabond.com/RV-Leak-R...ducts-s/22.htm

If you have a specific area of concern or detail just upload pic here and maybe I can help.