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Jerome J. Lazar, CCS, CSI
Senior Member
Username: lazarcitec

Post Number: 1988
Registered: 05-2003
Posted on Wednesday, April 17, 2019 - 07:50 pm:   Edit PostDelete PostPrint Post

Who is responsible to specify the concrete topping? Architect or Structural PE? Pavers over mortar bed will be installed over concrete topping.
Michael Chusid, RA FCSI CCS
Senior Member
Username: michael_chusid

Post Number: 477
Registered: 10-2003


Posted on Wednesday, April 17, 2019 - 07:55 pm:   Edit PostDelete PostPrint Post

Trick question. If the owner has hired the architect to design and specify building, the architect is responsible even if architect hires a PE consultant. But you knew that. Can you restate question.
Michael Chusid, RA FCSI CCS 1-818-219-4937
www.chusid.com www.buildingproduct.guru
Jerome J. Lazar, CCS, CSI
Senior Member
Username: lazarcitec

Post Number: 1989
Registered: 05-2003
Posted on Wednesday, April 17, 2019 - 08:17 pm:   Edit PostDelete PostPrint Post

Not a trick question. Architect is calling for a 2 in thick conc topping to be covered with pavers, which means traffic of some kind, would that not make the topping structural? PE refuses to specify topping.
Brian Payne
Senior Member
Username: brian_payne

Post Number: 175
Registered: 01-2014
Posted on Wednesday, April 17, 2019 - 08:25 pm:   Edit PostDelete PostPrint Post

Sounds like an unbonded overlay. 2 inch sounds too thin.

https://www.cement.org/docs/default-source/fc_concrete_technology/is144-07t-resurfacing-concrete-floors.pdf?sfvrsn=4&sfvrsn=4
Jerome J. Lazar, CCS, CSI
Senior Member
Username: lazarcitec

Post Number: 1991
Registered: 05-2003
Posted on Wednesday, April 17, 2019 - 10:49 pm:   Edit PostDelete PostPrint Post

Thanks Brian for the info., this project has over 3000 pages of specs, single side, for arch and struct, its not a high rise, but it is a condo, so it will eventually wind up in litigation. My contract does not include Div 3 specs, I am almost done, trying to avoid adding more spec sections.
Jeffrey Wilson CSI CCS SCIP
Senior Member
Username: wilsonconsulting

Post Number: 278
Registered: 03-2006


Posted on Thursday, April 18, 2019 - 10:20 am:   Edit PostDelete PostPrint Post

There are no rules that govern responsibility for authoring spec sections -- only agreements among the parties, which are negotiable. Since last-minute surprises are common in our business, my agreements allow for accommodating additional spec sections -- and adjusting the fee accordingly.
Jeffrey Wilson CCS CSI SCIP
Wilson Consulting Inc
Ardmore PA
Jerome J. Lazar, CCS, CSI
Senior Member
Username: lazarcitec

Post Number: 1994
Registered: 05-2003
Posted on Thursday, April 18, 2019 - 10:29 am:   Edit PostDelete PostPrint Post

adjusting the fee, I want your clients, there is no fee adjustment with this client.
Jeffrey Wilson CSI CCS SCIP
Senior Member
Username: wilsonconsulting

Post Number: 279
Registered: 03-2006


Posted on Thursday, April 18, 2019 - 10:51 am:   Edit PostDelete PostPrint Post

Well, you have to train them, my friend -- I mean "adjust expectations." Most of my clients are amenable to this when I explain that the intent is to share the risk fairly. The fee is just as likely to go down when the estimated number of sections is less.

The alternative is to take on the entire risk yourself that there will be more sections to develop -- in which case there would hopefully be more "fat" in the fee.

Of course this doesn't help manage time. If you're not able to accommodate a last-minute addition, that's what addenda are for -- right?
Jeffrey Wilson CCS CSI SCIP
Wilson Consulting Inc
Ardmore PA
John Bunzick, CCS, CCCA, LEED AP
Senior Member
Username: bunzick

Post Number: 1775
Registered: 03-2002
Posted on Thursday, April 18, 2019 - 03:55 pm:   Edit PostDelete PostPrint Post

I would not consider a topping to be structural. Many things architectural have performance criteria with a structural "angle." For example: your flooring may need to resist heavy rolling loads, like a fork lift; an access floor has a load limit; a window must resist a wind load; an exterior rolling door needs to resist a wind load; a shelf bracket need to hold the load imposed upon it; an interior stud partition, especially a tall one, needs to be stiff enough; etc. None of these require a structural engineer, yet they all have loads imposed on them.

The topping manufacturer can likely help with the particular requirements of your project.
William C. Pegues
Senior Member
Username: wpegues

Post Number: 970
Registered: 10-2002


Posted on Thursday, April 18, 2019 - 05:00 pm:   Edit PostDelete PostPrint Post

All,

I have encountered this numerous times, most especially through the Dallas office when I was with WDG (retired now -grin!), as well as a few times in the DC area. All of these were on elevated roofs - that is to say, high rise some 15 stories or more above grade. One of these in DC was a corner condition where the pavers on the concrete overlay was subject to wind uplift requirements a bit higher than typical and they wanted to use a tile that was thin and with grouted joints, it was a custom modification for a high end residential unit.

In all these cases, the roof membrane was a protected membrane system, with the insulation above the membrane and the concrete topping above the insulation. Probably your worst case situation.

One thing about concrete on top of the roof membrane, where in normal circumstances you can get a single source warranty from the membrane manufacturer that covers the removal and replacement of everything above the membrane, it is almost never available for a concrete overlay. Pavers on pedestals or leveling tabs, pavers set direct to insulation, specialized wood ‘pavers’, vegetated roofing components, all can be part of a single source membrane where any problems in the future cover removal and replacement, but not concrete. And one of the cautions in that is that typically the concrete if needed to be removed to investigate for leaks is going to result in destruction of the insulation in a PRM type roof...or destruction of the membrane itself in a non-PRM roof. And, removal and replacement of the concrete, tiles/pavers, and membrane damaged by removal will be an additional expense above and beyond the repair of any leak.

So, make sure all are aware of that. The owner may want to talk to their contractor for the actual membrane to be used to see what will or will not be covered by their warranty in these instances. Interestingly, because it may be less costly to delete the warranty requirements entirely for this area of the roofing because it won’t cover very much anyway. Not something you want to specify, but, a good point of advise to the Owner. All that may prevent your phone ringing late some ‘dark and stormy night’.

As to the solutions, first, make sure you are using a membrane for the roof in this area that you have 100% confidence in. There are many really good ones out there, but list only those by name you are familiar with personally and if the GC wants to substitute ‘something similar’ just say the liability is on them as you can’t vouch for others.

As to the topping/concrete material, no, it is definitely not structural. It’s definitely architectural. And, if done correctly you can get a single source warranty covering any cracking or failures through weather, or normal wear and tear - and in some conditions it may even be available as a lifetime warranty.

How is easy, you need to use a single manufacture for all products from the bottom of the topping ‘slab’ to the top of the tile/pavers, exclusive of the tile/pavers themselves. Any additional different manufacturer for any component is going to make the warranty non-lifetime and may end up voiding any warranty at all.

The topping slab - its not just ‘concrete’. It’s a specialty product. The 3 major tile setting system manufacturers. (Mapei, Laticrete, and Custom) all have total solutions that cover all components from the mix that will make up the slab, any separation membranes between the slab and the insulation or membrane, any bonding or slip membrane between the ‘slab’ and the setting system and the tile/pavers, and any grout.

What you do is your call up the local rep (or national sales manager is even better), describe the situation, perhaps send them plans of the area, they will send back all the products, the way the system goes together and a section showing what is where that needs to get onto the drawings (or appended at the end of the spec section). From the specific products of the manufacturers, you assign the same generic name and label those on the section accordingly.

There, 3 products for competitive pricing.

Make sure you ask for warranty coverage and ask about lifetime. Spec the best quality warranty (which will drive different products in the sandwich) available, let any price saving be adjusted by adjusting the warranty and different products as opposed to introducing a different manufacturer you have no familiarity with.

Ps - after 43 years, I have never had a project with a leaking roof, including these specific conditions, and even after all this time some 30+ year old roofs never replaced that have never leaked...except 1 - and that is because the contractor had the roofer install the roof and then had him come back later for ballast and insulation in the meantime of which the GC had a small tractor running around on the protection board carrying materials that were lifted up by crane that was only discovered a year after completion and which needless to say, the GC had to pay for all the repairs.
William C. Pegues, FCSI, CCS, SCIP
Jerome J. Lazar, CCS, CSI
Senior Member
Username: lazarcitec

Post Number: 1995
Registered: 05-2003
Posted on Thursday, April 18, 2019 - 05:14 pm:   Edit PostDelete PostPrint Post

William, you have described my project exactly, except its a 5 story, not a highrise. Not sure why I have never specified this topping on other projects, in my current project the Architect is calling out a 2 in thk concrete slab over iso insulation board.
William C. Pegues
Senior Member
Username: wpegues

Post Number: 971
Registered: 10-2002


Posted on Thursday, April 18, 2019 - 05:26 pm:   Edit PostDelete PostPrint Post

Jerome,

Tell the architect that he must NOT call this a ‘concrete topping slab’. Choose another name that makes it part of the setting system for the final exposed material. If its tile or pavers, a note on the drawings that specifically states to refer to the tile/paver section you use for specifying the setting system ‘sandwich’. Otherwise, it will end up as a concrete slab and that’s not so good.

IF (and this has been done as well) the concrete is meant to be the final exposed surface, again talk to the 3 manufacturers I listed. They have a solution for this as well. You want them, as you can get a warranty for cracking or weather related problems and wear and tear over time. With ‘concrete’ you can’t get any kind of special warranty and it will most likely crack.
William C. Pegues, FCSI, CCS, SCIP
Jerome J. Lazar, CCS, CSI
Senior Member
Username: lazarcitec

Post Number: 1996
Registered: 05-2003
Posted on Thursday, April 18, 2019 - 05:53 pm:   Edit PostDelete PostPrint Post

The Architect is stubborn, but I agree with you, fortunately the concrete topping is not exposed, its serving as a base for concrete pavers set in mortar. Of course this is a condo, so I am being careful what I specify, I will reach out to Mapei or Laticrete. This job is my current albatross, 77 condo units and 22 key hotel within three buildings, one is 3 stories the other two 5-stories, the condo unit building is based on current code and is to be LEED Silver the other two buildings based on previous code, simple enough, yet the amount of specs is staggering, I expect at least 5000 pages in 3 volumes, if only I was being paid per page.
Jerome J. Lazar, CCS, CSI
Senior Member
Username: lazarcitec

Post Number: 1997
Registered: 05-2003
Posted on Thursday, April 18, 2019 - 05:59 pm:   Edit PostDelete PostPrint Post

William C and John B, good to read your posts again, I do miss posts from John R, RIP. Perhaps Nathan W and David M will join the party. Am I the only one wondering why there are so many unregistered posting this week asking the same question about what type of AVB to use over exterior board? Been working many long hours this week, perhaps I a paranoid.
William C. Pegues
Senior Member
Username: wpegues

Post Number: 972
Registered: 10-2002


Posted on Thursday, April 18, 2019 - 07:23 pm:   Edit PostDelete PostPrint Post

Jerome,

Ok, then I suggest you contact Mapei, they are typically and always have been very fast. Here is my contact information for them.

Mike Granatowski
National Architechtural Manager, Mapei
mgranatowski@mapei.com

I have a mobile number for him, but not sure if it is current...
1 (949) 212-2363

Not sure where his office is, he is typically all over the country on any given day.

I have known him since ARC-US in 2011. I always contacted him direct, as well as worked with the local regional rep for the DC area.

Feel free to mention my name, and WDG from DC, he will know right away then (or the specifier who fences) - you might even get better service -grin!!. I have not had a chance to talk with him directly since I retired the beginning of 2017, but according to the local rep here who comes to my CSI Chapter, my name comes up from time to time and apparently in a good way.

He will need to know the roofing membrane system and the roofing insulation that the ‘slab’ is going on top of, he may recommend a separation sheet of some kind. And he will need to know the manufacturer and type and name of the paver for the bond coat to the ‘slab’ as well as the type of grout to be used in the joints.

I think you will be impressed with the support you get.
William C. Pegues, FCSI, CCS, SCIP
Jerome J. Lazar, CCS, CSI
Senior Member
Username: lazarcitec

Post Number: 1999
Registered: 05-2003
Posted on Thursday, April 18, 2019 - 07:46 pm:   Edit PostDelete PostPrint Post

So William, you are retired, what's that like? Unfortunately I will never be able to retire, too many past mistakes, family all gone but my mentally ill daughter, Andi, as long as my memory is intact I will work, and take care of Andi, actually we take care of each other. But life is hard, spec writing in Florida is tough, after 30 years you think it would improve, Contractors remain in control at least in the private sector. Clients are fixed on previous fees. Never a dull moment, but I work too many hours, being a one man show. William keep checking in with us, your knowledge and insight is always appreciated.
William C. Pegues
Senior Member
Username: wpegues

Post Number: 973
Registered: 10-2002


Posted on Thursday, April 18, 2019 - 10:22 pm:   Edit PostDelete PostPrint Post

Jerome,

Sorry to hear about your situation, I did not know.

I have volunteered for a number of related things. Reston Planning and Zoning Committee (reviews all new projects in Reston, which is a lot since the Metro Rail system is expanding this way), Reston’s Environmental Advisory Committee, and have “Adopted A Spot” for keeping it clean as well as encouraging native plants and removing non-native plants (its about the size of a football field). I am taking a Master Gardener’s class with the county as well. Activity wise, I continue with fencing, currently ranked 5th in the country in foil for my age group. And of course, keeping my hand in with doing work for selected manufacturer’s and guide specs.

I know about spec writing in FL. About 7 years ago or so WDG started doing work there. Our first project after we did the specification, the project manager came back and said that the contractor told him specs were not important and not required. So, yes, I sort of understand the situation -grin! Currently the Dallas office is involved in the major “Midtown Tampa Bay” project, and a project that completed last year, Kalea Bay, in Naples won an award there. Regardless though, specifications are written for all projects and delivered to the Owner even if the GC decides not to use them.
William C. Pegues, FCSI, CCS, SCIP
Jerome J. Lazar, CCS, CSI
Senior Member
Username: lazarcitec

Post Number: 2001
Registered: 05-2003
Posted on Friday, April 19, 2019 - 05:43 pm:   Edit PostDelete PostPrint Post

Architects are last to know if specs are being used, they are getting burned because their drawings reference the specs...Owners don't care because they are signing contracts for less construction cost if the specs are not being used, this has been going on in SFL for 20 years. The smarter Architects are ignoring the Contractors and managing the project as if the specs were being used, juicy litigation expected.
William C. Pegues
Senior Member
Username: wpegues

Post Number: 974
Registered: 10-2002


Posted on Friday, April 19, 2019 - 05:49 pm:   Edit PostDelete PostPrint Post

Yes, that is exactly what WDG did, managed the projects as if the specs were part of the package.

We also had a project up in Cleveland that was similar a number years prior to our FL experience that prepared us well for that. There the GC kept coming back saying the product that they were using was not working well and wanted to know how to fix things. They had written a contract with the Owner that specifically excluded the specifications, where our contract with the owner had the full contract package. They were attempting to treat all the drawing information as ‘generic’ and doing whatever product they wanted to use. We pointed this out and simply said, refer to the specifications. Lots of heated words but not really involving us, just between the GC and the Owner.
William C. Pegues, FCSI, CCS, SCIP
Jerome J. Lazar, CCS, CSI
Senior Member
Username: lazarcitec

Post Number: 2003
Registered: 05-2003
Posted on Friday, April 19, 2019 - 05:56 pm:   Edit PostDelete PostPrint Post

As long as the Architect follows thru ,the Courts buy it, even on Condo work. PE's if part of the Architect's team have to play the game too.
Mark Gilligan SE,
Senior Member
Username: mark_gilligan

Post Number: 875
Registered: 10-2007
Posted on Friday, April 19, 2019 - 11:35 pm:   Edit PostDelete PostPrint Post

The concrete topping is not designed by the structural engineer and it is not needed to address a structural issue within the structural engineers scope so naturally the structural engineer would not specify the topping slab.

You either create a separate concrete specification section or you can negotiate changes to the structural engineers specification section that addresses your needs I suggest the former.

Remember the specification manual contains specifications from multiple consultants. Nothing prevents multiple consultants from collaborating in the writing of a specification section. Having said that when this is done there needs to be a record of which consultant was responsible for which provisions.
William C. Pegues
Senior Member
Username: wpegues

Post Number: 975
Registered: 10-2002


Posted on Sunday, April 21, 2019 - 04:36 pm:   Edit PostDelete PostPrint Post

Jerome,

I sent a note of to Mike, and he responded...

“Have your friend contact me and yes we can put together a complete system.

Mike Granatowski
MAPEI
Director Architectural & Commercial Projects
949-212-2363 “

He is great, fast, and through. He can also help present it so that you can explain it to the architect. He, and Mapei in general, were my go to group for any tile setting system questions, including some pretty strange renovation situations.
William C. Pegues, FCSI, CCS, SCIP

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