FAQ’s

  • How thick does the concrete need to be?

    When applied as an Admix Xypex requires a minimum concrete thickness of 150 mm to give a Grade 3 (BS:8102), habitable environment, whilst to achieve a Grade 4 (BS:8102), ‘archive’ environment the minimum thickness required is 300 mm.

    When a coating is used the thickness can be reduced as shown in the following test results.

    “A major independent testing laboratory performed concrete waterproofing tests on Xypex in accordance with Army Corps Permeability Specification CRD-C48-73. The results showed that a two coat application of Xypex on 50 mm thick 13.8 MPa porous concrete totally eliminates leakage at pressures of at least 123.4 m of head pressure (1207 kPa), the limit of the testing apparatus”

  • Is Xypex warranted?

    All Xypex products come with a manufacturer’s warranty.

    For Xypex Admix a full warranty is available with a complete site service offer. This entails:

    - Instigating QA procedures at the batching plant and keeping a log of all concrete supplied.
    - Checking and signing off joint details.
    - The drawing up of any project specific joint details as required.
    - Checking and signing off any cast in pipe penetrations.
    - Signing over of a completely dry structure with a full 12 year warranty (extended warranties of 25 or 50 years are available at a small additional cost).
    - Remedial applications can also be warranted by using specialist applicators. Please contact SMR Projects Technical Department for more details.

  • What finishing’s can be applied to concrete containing Xypex?

    When Xypex Admix is used, as long as the hydration process is complete it can be treated as any other piece of concrete.

    Where a Xypex coating has been applied, paint, epoxy coatings, cement parge coats, plaster and stucco can be applied or installed.

    Applications of Paints, Epoxies or similar coatings

    Xypex requires 21 days of curing and crystal generation before the application of any paint or epoxy. Washing the Xypex surface with a 3 - 5% muriatic acid solution is recommended before applying the coating. Be sure to flush all acid off the wall.
    Application of grout, Cement parge Coat, Plaster or Stucco

    It is important that any other cementitious system be applied over the Xypex coating before the Xypex crystals have had time to plug the pores of the concrete. Therefore, grouts, cement parge coats etc. should be applied after the Xypex has completely set but while it is still “green” (8 to 48 hours). Use of a bonding agent is recommended.

    Note: Xypex Chemical Corporation makes no representations or warranties regarding the compatibility of Xypex products with plasters, stuccos, tiles and other surface applied materials. It is the responsibility of the installer of these surface-applied materials to take whatever measures are necessary, including testing, to ensure acceptance by or adhesion to the Xypex treated surface.

    For more instructions, alternative application methods, or information concerning the compatibility of the Xypex treatment with other products or technologies, contact the SMR Projects Technical Department for more details.

  • What are the application advantages of using Xypex instead of membranes?

    The crystalline nature of the Xypex waterproofing system provides many application advantages over traditional barrier products:

    - Xypex does not require a dry surface; in fact, a wet surface is necessary when coating.
    - Xypex does not require costly surface priming or levelling prior to application.
    - Xypex cannot puncture, tear or come apart at the seams.
    - Xypex does not require protection during backfilling or during placement of steel, wire mesh or other materials.
    - Xypex can be applied on either side of a concrete surface - the negative or the positive (water pressure) side.
    - Xypex does not require sealing, lapping and finishing of seams at corners, edges or between membranes.
    - Xypex is less costly to apply than most other methods.

    Read more about membranes here.

  • How is Xypex different from other products?

    The Xypex crystalline system for concrete waterproofing is substantially different from traditional barrier products (membranes, cementitious coatings):

    Xypex creates a crystalline structure deep within the pores and capillary tracts of the concrete mass to prevent the penetration of water and aggressive chemicals. In contrast, barrier-type products function only at the surface of the concrete.

    Because Xypex is not dependent on surface adhesion to achieve its waterproofing effect, it is permanently resistant to extreme hydrostatic pressure.

    - Xypex is warranted to seal hairline cracks up to 0.4 mm.
    - Xypex is not subject to the deterioration problems encountered by membranes.
    - Xypex is permanent and reactivates whenever water is present.

  • How resistant is Xypex to aggressive chemicals?

    Based on independent testing according to ASTM C 267-77 “Chemical Resistance of Mortars”, Xypex is not affected by a wide range of aggressive chemicals including mild acids, solvents, chlorides and caustic materials. Because Xypex is pH specific (not chemical specific) it will protect concrete from any chemical whose pH range is 3.0 to 11 in constant contact, or 2.0 to 12.0 with periodic contact.

  • How long does Xypex last?

    A Xypex application, unlike most other systems, is permanent. Its unique, dendritic crystalline growth will not deteriorate under normal conditions.

  • How deep does the Xypex crystalline formation penetrate the concrete?

    The Xypex Chemical reactions that initially take place at the concrete surface or immediately adjacent area will continue deep into the concrete structure. Independent testing measured the depth of Xypex crystalline penetration into a cast-in-place concrete block at 30 cm. The test concrete sample was coated on the top surface with Xypex Concentrate and left outside the research laboratory in ambient conditions for 12 months.

  • What is the appearance of Xypex treated concrete?

    Concrete with Xypex added as an Admix will look no different to normal concrete, Xypex will not change the look or the finish.

    As a coating, Xypex normally produces a grey-coloured, cementitious surface.

  • How waterproof is Xypex-treated concrete?

    Either as a coating or as an Admix, Xypex, if applied in accordance with the specification will give a minimum of a Grade 3 (BS:8102) completely dry and habitable environment.

    A major independent testing laboratory performed concrete waterproofing tests on Xypex in accordance with Army Corps Permeability Specification CRD-C48-73. The results showed that a two coat application of Xypex on 50 mm thick 13.8 MPa porous concrete totally eliminates leakage at pressures of at least 123.4 m of head pressure (1207 kPa), the limit of the testing apparatus.