Installation Instructions

Capillary Bunker Liner Construction and Installation Instructions

We provide our clients with detailed information and guidelines to support successful installations of the Capillary Bunker liner. If you can’t find something or have questions, please contact us.

Capillary Bunkers Installation Instructions (English)

Capillary Concrete Bunker – installation Guidelines – Step-by-step Instructions
How to measure the bunker area

Capillary Bunkers – Installation in 5 Steps

  • Prepare the subgrade: Ensure that all bunker drains work properly and the subgrade is positively pitched, stable under foot, smooth, compacted and free of debris.

  • Install turfgrass: Grassing around the perimeter should take place prior to installation and be secured to the soil by roots or staples.

  • Define the edge: Excavate the subgrade under the turf so you will be able to apply Capillary Concrete under the sod to help protect the edge.

  • Install Capillary Concrete: Cover bunker subgrade area with Capillary Concrete; cure 24 hours.

  • Install sand: Place bunker sand over Capillary Concrete; saturate with water.

Detailed Instructions 

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  1. When the ready-mix truck arrives at the job site, you will need to ensure the correct consistency of the Capillary Concrete before installation can begin. Before discharging any mix, ask the driver to spin the truck 5 revolutions to adequately mix the product. (It’s been mixing since it left the plant, but we find this to be a good way to ensure mix uniformity) Now it’s time to perform a HAND SQUEEZE TEST as shown here. Ask the driver to discharge a small amount of the Capillary Concrete mixture into the utility vehicle you are using  to haul the mix to the bunker. It should be shiny and look like melted chocolate and rock. Take a handful of the mix and squeeze it in your hand and release. The paste must be creamy and sticky enough for the aggregate particles to adhere to the vertical surface of your hand. If the paste is dry and powdery, the mix is a little too dry and you need to ask the driver to add water to the mixer truck. Never add more than 1 gallon of water at a time (unless otherwise instructed by an onsite Capillary Concrete representative), check after, ask the driver to turn the drum a minimum of 15 revolutions before checking the mix again. Continue this process until the mix has the feel of melted chocolate. Be careful not to add too much water. It’s always better to add a little at a time.
    We cannot take the water out once it has been put in the mixer. The paste should NEVER be drippy and runny when you perform the  hand squeeze test. The mix should always have the consistency of melted chocolate. Continue to monitor the consistency as you install – YOU MUST perform the hand squeeze test occasionally to ensure consistency during the installation. An additional gallon of water may  be required after a few loads have been installed. If so-ask the driver to add one gallon and rotate the drum 15 times before discharging more mix. If the mix is extremely wet and runny when the ready-mix truck arrives, ask the driver to spin the drum for 5 minutes to try to dry the mix up a bit. If that doesn’t work and the discharged pile for testing has clogged up void space, you should refuse the truck, send it back to the plant, and contact your Capillary Concrete Representative immediately. DO NOT install Capillary Concrete if the mixture is too wet.

  2. If the subgrade is dry, it should be lightly misted prior to placement of Capillary Concrete. Do not let the floor get muddy during installation, and make sure floor is always smoothed out before installation of Capillary Concrete. NEVER WALK ON THE WET CAPILLARY CONCRETE MIX.

  3. Once the batch is properly mixed, begin in one corner of the bunker by spreading the mix to a depth of 2 inches (50mm) (using depth gauge rings). Use plastic bunker rakes or the aluminum placer tools to drag out and level the product. DO NOT walk on the product in the bunker. This will compress the product and restrict water flow. We want to preserve as much open space for water flow as possible.

  4. Use the textured roller or trowels to finish and lightly compact the surface. The entire surface of Capillary Concrete must be lightly compacted to provide a smooth surface and bond the product together. Keep the roller damp during the rolling process. It is important to work quickly during this step. The sooner the product is smoothed and rolled the better.

  5. The edge of Capillary Concrete must be no less than 2 inches thick. A hand trowel should be used to compact and finish the edge of the material around the bunker edge (If desired, this is also the location of the drip-line irrigation option). Care must be given to prevent loose aggregate pieces from adhering to the exposed soil edge. Any loose pieces should be removed immediately.

  6. Once an area or batch section is finished, it must be covered immediately with 6 mil plastic. Black plastic is preferred on cold days, clear plastic is preferred in the summer. Covering is important to reduce moisture loss and improve curing and strength of the mixture, and covering MUST BE performed in any weather. Place staples in the plastic every 3 feet around the perimeter of the bunker and as close to the mixture as possible to reduce air between the plastic and mix. If there are seams between plastic pieces, use something heavy to hold the seams down. Remember we want to reduce the amount of air getting to the product as it cures. This step also keeps debris and water from getting onto it during set up.

  7. The plastic cover must remain on product for a minimum of 24 hours (48 hours in cold or wet conditions). Then, remain covered until bunker sand can be installed. This helps the product cure and will keep the product clean and debris free.

  8. Before installing the bunker sand (minimum of 24 hours after installation must pass), remove the plastic and clean the base of the bunker with a backpack blower to remove any loose surface pieces that may not have adhered during the rolling phase of the installation. Check the edge for loose pieces as well and remove them from the soil edge. Do not allow concrete to turn light-grey in color. The product needs to stay hydrated before sand is applied, if not keep covered.

  9. Now perform the water drainage test to confirm that water rapidly drains through the product. This must be done to activate the Performance Guarantee. Do not “blast” high pressure water on the freshly installed Capillary Concrete – a shower spray is preferred over a steady stream. See the film: The Test of Drainage.

  10. Bunker sand can now be installed (using a conveyor, loader, or utility cart etc.) to the required or specified depth according to  the Soil Moisture Release Curve. Do not drive directly on the new Capillary Concrete bunker during sand installation. It is recom-mended to begin sand installation on an edge and push the sand out across the bunker using a sand rake or similar machine while keeping vehicles on plywood on top of the sand layer. Once the sand has been installed, saturate the sand with a spray nozzle so as to not flood the sand to where fines can separate. This moisture will help the product continue to cure and help the sand firm up.


If requested by the CONTRACTOR, OWNERS REPRESENTATIVE, SUPERINTENDENT, or GOLF COURSE ARCHITECT, Capillary Concrete will provide a technical representative for installation assistance and consultation for one (1) full day on site at the start-up of a Capillary Concrete installation for the cost of basic expenses and related costs. Additional days of consultation may be requested at the same expense rate. Please provide a minimum two (2) weeks’ notice to arrange this service. For more specific questions, contact us.