Bond beam vs coping

pcollins22

Well-known member
Aug 7, 2016
98
Gilbert, AZ
Hi all -

About to order my coping after getting shotcrete last week.

I have what I think is a silly question but I haven’t seen addressed before… If my bond beam is 12 inches wide, does it matter if I choose a 12” or 16” coping? The 12” coping will be completely covered on the bond beam (with the 2” of overhang in the pool), and the resulting other pavers that will butt up to it will also be resting on the last 2” of the beam (I know not to secure it so the patio can float).

But the 16” coping would overhang 2” past the bond beam. Is that kosher and can be filled with compacted substrate prior to laying down the paver behind it?

Which would you choose?
 
You can’t use 12” coping on a 12” bond beam. You don’t want your decking material anywhere near your bond beam. You want the coping to fully cover the bond beam and then there should be an expansion joint between the deck and bond beam.

If your only choice is 12 or 16, then use the 16” coping and make sure the grade is level and compacted up to the top of the bond beam.
 
  • Like
Reactions: pcollins22
Also, make sure that the bond beam and interior and exterior gunite surfaces are covered with cementitious water barrier layer such as HydroBan or similar product. You do not want the gunite shell wicking water up to your coping or behind the tile line.
 
  • Like
Reactions: StuartBound
Dang, I’m glad I asked…

Thanks for the info on waterproofing. It seems standard practice that most contractors just like to do the tile line (less work), but I’ll have them do the entire water line as well as up and over the top and exterior side of the beam.
 
Dang, I’m glad I asked…

Thanks for the info on waterproofing. It seems standard practice that most contractors just like to do the tile line (less work), but I’ll have them do the entire water line as well as up and over the top and exterior side of the beam.

The water barrier layer helps to keep moisture from getting up to the coping. Natural stone coping can develop efflorescence from moisture infiltration. It can also weaken the mortar bed that holds the stone to the bond beam. And yes, a lot of contractors will simply slap it behind the tile and call it a day. Typically you want about 12” of water barrier on the interior so that 6” tile has plenty of it to protect the thinset set and grout. Laticrete products are great if you can get them locally.
 
  • Like
Reactions: pcollins22
Thank you.

Jesus I still can’t believe I can’t use a 12” coping as planned. I’m now freaked out a bit, as the rest of my decking isnt going in until after pool finish…. Which means I won’t be able to properly level and compact the dirt next to the bond beam where the 16” coping material will overhang. I don’t have confidence that this could be feasibly accomplished after the coping has been set, when a different crew comes back to do the rest of the decking

But at the same time I can’t imagine the masonry crew having to either trim every piece of coping by 2” OR chisel down/notch my bond beam 2” around the entire pool so that the coping will be flush with the bond beam.
 
@AQUA~HOLICS … any thoughts on using 12” coping on a 12” bond beam with the decking in contact wit / overlaying on to the bond beam?

I say no but you’ve got way more experience than I ever will …
 
It is all about getting a good expansion joint with the pool structure and deck uncoupled.

Is the 12” bond beam really 12” all around or is it thicker or thinnner in places? Shotcrete is rarely precise in their dimensions. There is always a difference between “As Designed” and “As Built”. That is construction.

You can only figure out what works by measuring and laying actual stones on the bond beam as constructed and seeing what layout works.

If the deck touches the bond beam then there is no expansion joint in that area.


Pre-Cast_Coping.png
 
  • Like
Reactions: JoyfulNoise
Can you show a picture of the coping material you’re considering or a link to it? Is the coping stone? Precast cement?

Also a picture of the bond beam?

The decking pavers?
 

Enjoying this content?

Support TFP with a donation.

Give Support
Placing foam like this along the side of the coping and bond beam preserves the integrity of the expansion joint while the deck is constructed...

 
Not much to add that hasn’t been explained in previous posts.
I don’t see notches inter graded on the backside of Bond Beams, typically they are a straight edge to the 45.
As stated before, no matter what type of material is used the most important element is not being in direct contact with the BB and having sufficient distance for movement of the flat work.
The concern about compaction under the coping overhang should be brought to attention of the deck contractor.
Is this project an Owner/Builder or a single contractor?
 
Here are pictures showing how a 12” coping vs 16” coping sits on the BB.

The BB is at least 12” throughout the pool, with some areas being 13-14” where the form was disrupted during shotcrete.

The coping is a limestone product that is about 1.5” thick.

This is an owner build. I have a contractor doing tile and coping, then a different contractor coming later to butt up the same coping pavers to finish and match the rest of the deck.
 

Attachments

  • 82CFD09D-D2ED-4E04-AB06-F7BECF5EDDC8.jpeg
    82CFD09D-D2ED-4E04-AB06-F7BECF5EDDC8.jpeg
    675 KB · Views: 32
  • 9537BB70-FA73-443C-ADFF-7462B3EDE2EC.jpeg
    9537BB70-FA73-443C-ADFF-7462B3EDE2EC.jpeg
    670 KB · Views: 26
Based on that info, I would want to use the 16” coping. It’s going to cost a lot more but you’ll be guaranteed the coverage you need. The decking contractor will need to regrade and compact on those areas close to the pool shell but that really shouldn’t be an issue. Being in AZ we get very little rainfall and so you don’t have to worry much about the fill material washing out or moving a whole lot. I’ve seen pools here with the decks butted right up against the coping with no damage to the pool. In other areas where there is more moisture, deck movement is a much bigger issue. But I would still caution you to have a robust expansion joint between the coping and the deck to avoid future headaches.
 
  • Like
Reactions: pcollins22
Have your deck contractor come to the job site before the coping is installed and have him see the product that is going to be installed for coping.
This will give him the opportunity to know what is needed to properly address the issues.
This goes the same as for the landscape contractor needs to be onsite prior to decking for the same reasons.
Being a few steps ahead of the current trade is one thing that I have to instill with owner builders to keep the surprises to a minimum.
 
  • Like
Reactions: pcollins22
How would you change the way the Bond Beam was constructed to use 12" coping? I am looking at coping choices from NPT and they do not offer anything but 12" in 3cm thickness. Would you have the gunite crew pull the forms and do a 45 cut at the back side?
 
I appreciate everyone’s input that’s far, and although this is a giant pain in my Rear, I’m glad I’m dealing with it now instead of after purchasing 1000 ft.² of 12” coping.

I have looked at thread upon thread regarding expansion joints, including the visuals presented by many of the experts here. However, one thing that I’m still not clear on, is: is an expansion joint visible? In other words, I know you don’t want the deck to be connected to your coping materials, but is there a physical separator between the coping border and the deck that creates this room for expansion? Or is it all underneath the material?

I guess a simpler way to say this is: if you are looking down when standing on the coping, will you see your material between the coping and the deck?
 
I guess a simpler way to say this is: if you are looking down when standing on the coping, will you see your material between the coping and the deck?

Yes, you see the flexible mastic covering the expansion joint.

 
  • Like
Reactions: JoyfulNoise

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.