Concrete Countertop Construction Techniques

Aug 22, 2024

Concrete Countertop Construction Lecture Notes

Overview

  • Progress made on countertops; island countertop poured.
  • Focus on preparing for pouring concrete before cold weather.
  • Using Concrete Countertop Solutions products (liquid additive, forms, form liners).

Preparation Steps

Material Setup

  • Cement Board Installation

    • Used 4x8 sheets of cement board, secured with screws to avoid seams.
    • Overhang needs to be accounted for; countertop should overhang the stone face by 2.5 inches.

  • Forms Installation

    • Front faces attached, secured every 10-12 inches.
    • Back edge secured with silicone sealant due to lack of screws.

  • Mesh Installation

    • Fiberglass mesh should be laid down and clipped every 10 inches.
    • Roll out mesh, flip to prevent curling while pouring.

  • Cut Outs for Appliances

    • Need to account for depth of cutouts for appliances like a power burner.
    • Adjustments made post-pour using a grinder.

Finishing Touches

  • Cement Board Edging

    • Edge of cement board cut back to avoid visible raw edges in the finished product.

  • Top Cap Stones

    • Pouring in place; previously considered separate pouring but opted for in-place.

Pouring Process

  • Mixing Concrete

    • Use colorant pigments; specific ratios for desired color.
    • Liquid additives prepared for each 60-pound bag of concrete.

  • Pouring Strategy

    • Start pouring at the top, work down to manage overflow.

Finishing Techniques

Tools and Methods

  • Finishing Tools
    • Magnesium float used to level surface and open pores.
    • Steel trowel utilized for a smooth finish; pressure and technique are key.
  • Sanding Edges
    • Use of diamond pads to remove any lip or imperfections on edges.

Post-Pour Actions

  • Sealing Countertops
    • Clean surfaces and apply acrylic sealer from Countertop Solutions.
    • Use different brushes and rollers for application; allow drying time between coats.

Challenges & Solutions

  • Air Pockets

    • Ensure thorough vibration during pouring to eliminate air pockets.

  • Cutting for Appliances

    • Measure carefully to allow appliances to sit flush with countertops.
    • Gradual cutting to ensure proper fitting.

  • Aesthetic Finishing

    • Achieve desired color and finish through careful mixing and application of sealers and polishing products.