Countertop Slab Calculator

Understanding Countertop Materials

Material selection impacts durability, maintenance, and cost over the lifetime of your countertop.

  • Granite Natural stone (6.5-7 Mohs hardness). Heat resistant to 1,200°F. Requires annual sealing. Cost: $40-100/ft². Typical slab size: 9'×5'6". Weight: 18-20 lbs/ft².
  • Quartz Engineered stone (7 Mohs hardness). 93% quartz + 7% resin. Non-porous, no sealing needed. Heat resistant to 300°F. Cost: $50-120/ft². Weight: 22-25 lbs/ft².
  • Marble Natural stone (3-5 Mohs hardness). Acid-sensitive. Requires bi-annual sealing. Heat resistant to 1,000°F. Cost: $60-140/ft². Typical thickness: 3/4" or 1-1/4".
  • Butcher Block Hardwood (1.5-2.5 Mohs). Oil monthly, sand yearly. Heat resistant to 150°F. Cost: $30-70/ft². Standard depths: 25" or 30". Weight: 5-7 lbs/ft².
  • Solid Surface Acrylic/polyester blend. Seamless appearance. Scratches repairable. Heat resistant to 350°F. Cost: $35-85/ft². Thickness options: 1/2" or 3/4".

Design Considerations

Seam Placement

  • Maximum length: 8'-10'
  • Minimum from edges: 6"
  • Avoid over appliances
  • Match grain at seams
  • Epoxy gap: 1/16"-1/8"

Overhang Specs

  • Standard: 1-1/2"
  • Bar top: 8"-12"
  • Support > 6" overhang
  • Bracket spacing: 24"
  • Cantilever ratio: 1:3

Support Requirements

  • Cabinet strength: 8 lbs/ft²
  • Support every 24"
  • Perimeter support: continuous
  • Level within 1/8"
  • Shim gaps ≤ 1/8"

Installation Clearances

  • Wall gap: 1/8"
  • Sink clearance: 3"
  • Cooktop gap: 3/16"
  • Corner radius: 1/2"
  • Edge relief: 1/16"

Edge Style Guide

  • Straight Edge (Eased) Standard profile. 1/16" radius. Lowest cost option. Best for modern designs. Easiest to clean. Labor cost: +$0-5/ln.ft.
  • Bullnose Full round profile. 3/4" or 1-1/2" radius options. Child-friendly. Traditional look. Harder to clean drips. Labor cost: +$10-15/ln.ft.
  • Beveled 45° angle cut. 1/4" to 1/2" bevel options. Modern appearance. Good water control. Medium difficulty cleaning. Labor cost: +$8-12/ln.ft.
  • Ogee S-curve profile. 1-1/4" or 2-1/4" depth. Elegant appearance. Most expensive. Requires more maintenance. Labor cost: +$20-25/ln.ft.
  • Waterfall Vertical edge continuation. Requires additional material. Modern luxury look. Complex installation. Additional cost: +$100-150/ln.ft.

Installation Specifications

  • Material Thickness Standard: 3cm (1-1/4"). Economy: 2cm (3/4"). Commercial: 4cm (1-1/2"). Laminated edges can double thickness appearance.
  • Joint Requirements Seam width: 1/16"-1/8". Epoxy color-match. Minimum piece size: 18". Inside corner radius: 1". Maximum cantilever: 1/3 of supported length.
  • Support Guidelines Bracket spacing: 24" o.c. Perimeter support: continuous. Spans over 24": additional midspan support. Load capacity: 100 lbs per bracket minimum.
  • Environmental Factors Expansion gap: 1/8" at walls. Temperature range: -20°F to +150°F. Humidity tolerance: 25-55% RH. UV protection needed for some materials.