Questions and Answers

We have listed some of the commonly asked questions we have received from customers on our website, Amazon or Ebay along with answers we, or in some cases, our customers have given sharing their experience.

Questions about StrataRise Low-Profile and Multi-Level Pedestals

  • Can the support pedestals be used with 4" wide joists?

    Yes - with the 1836, 2442, 3560 & 4166 pedestals the joist will overlap by about 1" on one side and we recommend placing the supports alternately from the left and right sides of the joists.

    Quantum Rubber Ltd. 04 June 2020

  • Are the 1836 & 3560 pedestals self-levelling? I have a slightly uneven patio we want to deck flat.

    These pedestals are height adjustable and can be used on slightly uneven ground as the large 200mm base area conforms well to the substrate. For sloping sites we offer levelling shims in 1, 3 or 5 degree angles which fit on top of the supports. Alternatively, packing shims under the base plates to ensure a firm seating is also okay.

    Quantum Rubber Ltd. 24 April 2019

    *New*: Self-Levelling pedestal ranges 2442 & 4166 are now available.

  • The pavement I’m building deck on is at a slight angle. Can these be used still?

    Depending on the angle we offer slope adjuster shims in 1, 3 and 5 degree options. For greater height differences than can be achieved with pedestals alone, we offer 25mm, 50mm and 100mm extensions.

    Quantum Rubber Ltd. 21 November 2019

  • Are these suitable for use on compacted stone?

    Yes, if the stone is well compacted but not suitable on loose stones.

    Customer: Joe Birt, 29 May 2019

    Quantum Rubber: We agree!

  • Can these be used directly on the ground to support joists off the ground?

    The surface needs to be fairly level and firm and not liable to be changed/softened by rain, etc. Provided the surface is stable, the 200mm base spreads load satisfactorily.

    Quantum Rubber Ltd. 22 May 2020

  • Can these be cut to use on the side and corners of a frame so you can’t see it?

    There are scribe marks on the base of each pedestal for use as guides when cutting for use at corners or sides. Further information is shown in our products section of the website.

    Quantum Rubber Ltd. 11 May 2020

  • How many would I need for a 4m by 3.5m deck using 6x2 joists?

    It depends to some extent on how far apart you will be placing the joists. Assuming you use 600mm approx. centres, for a professional, commercial-quality installation, 42 to 45 pedestals would be sufficient.

    Quantum Rubber Ltd. 27 February 2020

  • Will these crack in freezing conditions?

    No - they are weather resistant and stable in low temperatures for intended uses. Sharp impacts with temperatures below -15°C could cause breakage. 

    Quantum Rubber Ltd. 29 October 2020

  • I am building a 3mx3m metal shed on flat concrete base using 47x150mm joists and 47x150mm beams across the joists. Are 4 pedestals/joist enough?

    It depends on how far apart you are spacing the joists, but assuming 500mm centres that would total 28 supports - with 6" joists there will not be any noticeable deflection.

    Quantum Rubber Ltd. 13 June 2020

  • Can these be used for a 7.2 x 4.2m sips garden studio?

    Yes, I used them under my summer house 5.1m x 3.2m. Just use as many as you can to spread the weight.

    Customer: Mr U. 28 June 2020

  • Will these support a timber frame for a 2.5m x 5m log cabin?

    Yes - We suggest you plan for 500mm centres for the support beams with pedestals at 500mm centres along each beam.
    Quantum Rubber Ltd. May 2020

    The specifications say each pedestal will support up to 800kg, so depends how heavy your cabin is.
    markh2311. 21 May 2020

    Yes that’s exactly what I used them for - a summer house of similar size
    Mr U. 20 May 2020

    I would think yes, they are quite strong and spaced at minimum interval should be ok, check manufacturer weight loading info.
    COLIN GARNER 21 May 2020

  • !. Can I use two 100mm extenders on a 3560 pedestal? 2. Can I use a 50 + 100mm ext on a 3560?

    You can use multiple 25mm, 50mm and 100mm extenders if required with the 3560ML pedestals.  Likewise you can use multiple of the 20mm extensions with the Flexi-level cradles.
    The extenders are designed to be used in combinations and multiples to achieve the necessary height adjustment ranges required.

    Quantum Rubber Ltd.  26 May 2020

Questions about StrataRise 1250 Flexi-Level Cradles for Joists

  • What size timber will the support fit?

    All standard 2" beams are suitable - the StrataRise 1250 Multi-Level cradle supports are designed to accept up to 50mm wide timber or synthetic joists. For greater cross section widths up to 100mm, you can use StrataRise 3560ML supports.

    Quantum Rubber Ltd. 26 April 2020

  • I would like to use these joist supports to support a shed base. Does anyone know the design life of these units please?

    We do not currently have specific lifespan information for this product. The Flexi-Level product is manufactured from polypropylene, which is known to be highly resistant to break down and is long-lasting. Polypropylene is used to manufacture a diverse range of products from underground piping to car bumpers; in the case of piping there are estimates of lifespans of up to 100 years. Polypropylene will start to break down in landfill after 20 to 30 years. For your intended purpose, subject to correct usage, the Flexi-Level should provide a solution that will outlast the lifetime of the shed.

    Quantum Rubber Ltd. 27 February 2020

  • Can these be used for garden decking if placed on small paving stones?

    Yes - should be fine as long the surface is level and firm.

    Quantum Rubber Ltd. 09 May 2020

  • Hi can anyone confirm Flexi level adjustable joist supports suitable for my 2 inch wide joist which is 50.8mm exactly?

    The Support is designed to accept standard 2" (nominal) floor and deck beams. Once planed the actual beam width is typically 48mm or less and that is what this product is designed to handle. Unplaned 50mm beams may fit, but we do not guarantee this. If necessary, it would be simple to adjust the beam thickness at the mounting points or increase the cradle opening slightly. If in doubt we would suggest using the Stratarise 3560ML-DF pedestal support instead as these will handle up to 3" wide joists. 

    Quantum Rubber Ltd. 21 October 2019

  • What size screw would you recommend for fixing the pedestal to the joist?

    Any small wood screw will do. The fastening to the joist is optional and only needed if you plan to lift the beams - it simply prevents losing the position of the cradle on the beam.

    Quantum Rubber Ltd. 08 May 2020

  • I am installing composite decking with battens on a concrete base; do the pedestals need to be screwed down to the concrete?

    Hi - I have used these pedestals under decking for a hot tub and a 8x6 garden hut on concrete slabs and Indian sandstone and didn’t fix the pedestals down.
    That was over a couple of years ago and they haven’t moved.
    Amazon Customer. 19 June 2020

    NO - the Flexi-Level cradle is designed to be free standing and does not need to be fixed down.

    Quantum Rubber Ltd. June 2020

  • Hi, these look like the kind of thing I'm after to level my deck. Could you help to explain what a 800kg point load is, to work out the qty for hot tub

    Hi - the best product for supporting a hot tub installation would be the 3560ML-DF Pedestal support which, as you mention, is tested to a point load of 800kg or 1760lbs. This means is each individual pedestal can support that weight at its maximum height extension (i.e. with just one thread engaged), and well over a ton at lower adjustments with more threads engaged. With structures such as decks, hot tubs, sheds, etc. the load is distributed over the entire area and is spread over all the support points - we recommend using around 5 pedestals per square meter so, for a typical hot tub installation, depending on size, you would likely use 10 support pedestals. This would support a minimum distributed load of 10 x 800kg - the equivalent of 8 metric tonnes - or 17,600 lbs
    With the Flexi-level cradle, which is the product about which your enquiry was initiated, the carrying capacity/point load is much lower, at around 160kg and, whilst they can be used for the application, we do not normally recommend this product for hot tub installations as you would need to use around 8 per square meter to provide sufficient support and load spreading. 

    Quantum Rubber Ltd. 30 September 2020

  • Circular hot tub - inner diameter is 160 cm. This works out at 7.3 kn/m2; using 300mm centres, is 6 per sqm still ok under the hot tub?

    If you use the FlexiLevel cradle for a hot tub we would suggest increasing the number to 8 to 9 per sq.m. You may wish to consider using the 1836LP-DF or 3650ML-DF pedestal supports instead. These have a much higher load-bearing capacity with each support being able to withstand point loads in excess of 800kg and they are what we normally recommend for Hot Tub installations - using these you would need fewer pieces, so costs will be similar, and you will have the capability of supporting far more load. When you add the weight of the water, and persons using the hot tub, and allow for their movements, etc. the pedestal supports would be the better solution.

    Quantum Rubber Ltd 28 September 2020