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  • 1.  Waterproofing

    Posted 10-28-2020 01:24 PM

    I have a client with a second floor bathroom entirely finished in custom cut Carrera marble; floors, walls, ceilings.  I discovered a slow leaking condition which is caused by the lack of waterproofing directly outside the shower extending to the area in front of and below the lavatories. (approximately 6 ft. by 3 ft.).  The owner is adamant about retaining the stone.  The marble floor cannot be matched due to color, quality and size.   Is there a method for top down waterproofing without removing the floor stones?




    Stuart Martin Berger, AIA CSI-CCS

    Director of Architecture


  • 2.  RE: Waterproofing

    Posted 11-11-2020 02:43 PM
    The marble floor you are describing most likely takes its water from joints. Typically the shower is separated and a membrane within the shower will take care of moisture toward the drain. Everything it seems points to how well the stone floor and joints are sealed. Over time the joints will deteriorate and moisture will penetrate below. Therefore, the only way I know to keep moisture at bay is to work all the joints and seal the entire floor properly including the shower. Care needs to be taken with the type of sealer used as some can discolor stone etc.

    Constantine Vasilios AIA
    Constantine D. Vasilios & Associates, Ltd.
    Chicago IL

  • 3.  RE: Waterproofing

    Posted 11-12-2020 06:47 PM
    Hi Stuart,
    I doubt very much a bit of splashing would cause a leak below. Most likely the shower pan is compromised. Water is somehow seeping under marble, finding its way downstairs in front of it. 
    Remove drain cover, install a test ball and flood the shower for 24 hours. Mark waterline. 
    once you verified this not the problem, open the ceiling and try to find a evidence for the source of leak.
    almost certainly will be a pipe, not the marble.
    I hope this helps

    Ivan Contreras, LEED AP, AIA
    Qualifier | Director
    Miami FL

  • 4.  RE: Waterproofing

    Posted 11-13-2020 08:46 PM
    I agree with Ivan.  The finish layer cannot reliably be the waterproofing layer.  The amount of water mentioned seems to have other sources than slight moisture.  The shower pan test is the best first course of action.  Drywall is easy to remove for further review...  Be careful for anyone who reviews, does the work and building occupants.  Mold is very common in these instances and can be very hazardous for health.  Take the utmost precautions for all.  All materials within 18 inches of water damage need to be evaluated.  Make sure someone has a penetrating moisture meter for testing. "Dry" is a measurement!

    Cheryl Ciecko AIA
    Cheryl Ciecko, Inc.
    La Grange IL