Builder Patched Decking with Grout not Caulk

zollinmj

Member
May 6, 2024
22
Virginia, USA
We notice that the concrete patch work our builder did during the pool renovation a couple years ago (to run the pool light) was done with grout against the coping rather than caulk. We already see the grout pulling away from the coping and are very concerned about water/ice and vegetation causing long term damage/issues with the pool and the pool beam.

I just wanted a sanity check that this is wrong and will cause a problem if not dealt with. I'm in the process of reaching out to them and am waiting to hear back what they say.

Thoughts? Advice?
decking1.jpegdecking2.jpegdecking3.jpeg
Thanks,
Matt
 
Last edited:
Show us pictures of the problem areas.

Grout is hard and does not pull away from anything.
 
Yes, thank you. "Expansion joint" was term I was looking for and thank you for the link, very informative.

Would a reasonable fix be to remove the section of decking and replace it while installing a 1/2"-1" expansion joint? I'm hoping the PB will see this and come to this conclusion, but obviously I want to be armed with good information and a reasonable plan/expectation.
 
Would a reasonable fix be to remove the section of decking and replace it

What section are you thinking of?

Show me on a picture.

while installing a 1/2"-1" expansion joint?

Expansion joint just needs to be 3/8" to 1/2" wide. A wider joint just takes much more mastic to fill.
 
What section are you thinking of?

Show me on a picture.
Yep attached. I'm thinking of the "new decking" highlighted in orange. Some additional context: our pool was a renovation job after it hadn't been maintained in 4-5 years from previous owner. The majority of the decking appeared to be in solid shape and the PB said it should be fine to keep. They had to remove one section to be able to run the pool light's electrical.
decking-6.jpg decking-4.jpg

Additionally, the PB did a number of things as part of the renovation: replaced coping, repaired pool beam, installed new tile, redid pool surface, made the pool more shallow, added a Baja shelf, added stairs, added pool light. Not an exhaustive list.


Expansion joint just needs to be 3/8" to 1/2" wide. A wider joint just takes much more mastic to fill.
Yeah, ok thanks.

Additional Pics:
decking-7.jpg decking-8.jpgIMG_9254.jpeg
 
replaced coping, repaired pool beam, installed new tile, ...

If you had a cracked bond beam and cracked tiles that fell off the root cause is the lack of the expansion joint.

Your contractor did not understand the root cause of the problem and fix it. Bond beams should never crack if the pool and deck are properly constructed.

You still have the same problem and need the expansion joint installed or you will have the same problem again in a few years.

I am still not following why you want to remove the section of the deck.
 
It looks like the PB put polymeric sand where the expansion joint should be. Just dig out the polymeric sand where the pavers meet the coping and put in the proper expansion joint(Mastic). In the first and second pictures of your first post, I can see what looks like some type of caulk in the joint between the coping and original concrete.
 
A bit of a delayed response.

@SecoSteve: Yeah good spot, that is polymeric sand NOT what I thought was grout. You're also correct that everywhere else around the pool there is mastic. The gap for the expansion joint (between coping and decking) is about 1/2" where they used polymeric sand and about 1" where they used mastic, fwiw. The PB came by to inspect it and said polymeric sand (he referred to it as G2) was acceptable as an expansion joint and that it will just need regular maintenance. But I see that you imply it's not and I also see this post saying the same. I can't imagine I'll be able to convince the PB of that so I imagine I'll just have to dig it out and redo it myself 😔.

@ajw22: I'm not sure I'm being as clear as I'm trying to be with my combo of writing and pictures, sorry about that. I think SecoSteve got to the crux of it. I am/was concerned about the material used between the coping and decking (in that one section) because it differs from the rest of the pool (which seems correct). I was wrong in my guess that replacing the whole section of decking was the correct answer.
 

Enjoying this content?

Support TFP with a donation.

Give Support
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.