geraldineb

Best way to waterproof our decking to weatherproof the underneath

geraldineb
2 years ago





We have a 2 storey deck and we are planning to install an outdoor kitchen on the lower level. However we have wooden planks on the upper level and water pools then pours through when it rains. Obviously we will have to replace the decking, so does anyone know of waterproof decking that doesn't cost too much and where we can get it? Or is there another way to waterproof the bottom level? We live in Canberra ACT

Comments (11)

  • PRO
    Beach Bathrooms
    2 years ago

    Have you considered Scyon ( external ) waterproof as exterior balcony, tile with a high rated exterior tile

    However

    A structural engineers report on existing timbers ( $500 +) is a necessity, Safety, and expected life of all existing timber/ and ootings

  • geraldineb
    Original Author
    2 years ago

    Thanks for that. I'll have a look at Scyon. And yes we've had a structural engineer check the existing timber and footings. It's perfectly sound and once we waterproof the underneath, we intend to put panels of some description between each of the posts. This will strengthen the whole structure.

  • imaginary_mary
    2 years ago

    I don't know how the cost compares but NexGen has aluminium waterproof decking

     https://nexgendecking.com.au/products/aluminium-waterproof-deck/

  • bargainhunter
    2 years ago

    Could you line the underneath with colour bond and the water would run to the edge. (It would need to have a slight slope of course)

  • robinfk
    2 years ago

    Have a look at Underdeck at http://www.underdeck.com.au/ . There are other companies around that do the same thing.

  • PRO
    Beach Bathrooms
    2 years ago

    My thoughts, Waterproof as a new structure on the existing joists/bearers ( check with structural engineer, if they can accept the additional weight, Scyon and Tiles )

    Waterproofing under, will not protect your timber decking from weathering and early maintenance

    and

    You have an intention to " fill in between "

    Do it as a professional, it will last for years and add value

  • PRO
    NexGEN Decking
    2 years ago

    We have waterproof options to suit.

    Check out the below links or give us a call on 1300 661 801.


    DryJoist - Three products in one. Waterproof Substructure, Joist system for Decking and a finished Ceiling underneath.

    https://nexgendecking.com.au/products/waterproof-deck-system


    Weatherstrip - NexGEN Weatherstrip is a proprietary extrusion uniquely crafted to fit snugly within the slotted edges of NexGEN decking, creating a watertight seal, preventing water from penetrating the surface of the deck

    https://nexgendecking.com.au/products/waterproof-decking-weatherstrip/


  • PRO
    Castlegate Home Improvements
    2 years ago

    Hi Geraldine

    Your enquiry to waterproof the underside of your balcony is one we receive a lot of.

    We build balconies, patios etc and line the undersides of such structures. From our experience in doing this for 25 years, we don't know of any system put into an existing structure that can be guaranteed 100% waterproof by the manufacturer of the product or the installer. I could be wrong however I'm sure there will be a disclaimer in your quote.

    We have used the NexGen system with success in a Cottesloe balcony (WA) and used a different system in Mullallo and Peppermint Grove (WA) within 4 years of each other. With the Mullaloo balcony, we've had no issue after 4 years of install however the Peppermint Gove balcony waterproofing system installed in Janaury 2021, approved by the engineer, had to be cut on a two unusual angles to meet the 300 mm beam. With the first down pour, it did leak and we returned twice to rectify the problem with installing additional flashings (covering the beautiful Merbau beam).

    It may be a case of starting over with removing the existing decking boards to install the waterproofing membrane and installing new decking boards on new framing, keeping in mind this will raise the existing floor level. The other consideration is that this is not a straight edge balcony so whatever waterproofing system is used has to be cut on a curve which may compromise the integrity of the membrane. You'll require a gutter and down pipes on the front of the structure also.

    Whatever you decide to do, make sure you engage with a company who knows what to do.

    Best wishes! Castlegate Home Improvements

  • geraldineb
    Original Author
    2 years ago

    Thank you for your detailed answer to my question. We've always known we would have to remove and replace the existing decking, but you're right, the shape of the deck could well be a problem. We're certainly looking for a company who knows what they are doing and who operate in Canberra. Can you recommend anyone?

  • PRO
    Castlegate Home Improvements
    2 years ago

    Hi Geraldineone, we’re in WA and unfortunately don’t know anyone in the ACT. Beach Bathrooms are right, you want to ensure the balcony has all the right approvals. It might even pay to get an engineer involved. Best wishes!