Craftflame

Understanding Substrate Characteristics

Each wall material has unique properties that determine how it responds to drilling and anchoring. The "drill-feel" technique helps identify material density through the resistance encountered during drilling. This tactile feedback, combined with visual inspection, enables accurate material identification.

This guide covers common wall types from 1920s brick construction to modern drywall systems, explaining the specific hardware requirements for each material's density and internal structure.

Solid Brick

Common: 1920s-1970s
Drill-Feel
Consistent resistance, fine dust, occasional red particles
Density
High - 120-140 lbs/ft³
Recommended Anchor
Metal sleeve anchor or wedge anchor
Drill Bit Type
Masonry bit, carbide-tipped
Load Capacity
Up to 50 lbs per anchor point
Brick wall texture detail

Concrete Block

Common: 1950s-Present
Drill-Feel
Hard surface, gritty texture, gray dust
Density
Very High - 130-150 lbs/ft³
Recommended Anchor
Wedge anchor or drop-in anchor
Drill Bit Type
Masonry bit, diamond-tipped for dense blocks
Load Capacity
Up to 100 lbs per anchor point
Concrete block wall surface

Drywall

Common: 1960s-Present
Drill-Feel
Soft resistance, white powder, hollow sound
Density
Low - 40-50 lbs/ft³
Recommended Anchor
Toggle bolt or wall stud mount
Drill Bit Type
Standard twist bit, 1/4" or larger
Load Capacity
Up to 25 lbs per anchor (without stud)
Drywall surface texture

Siporex (Aerated Concrete)

Common: 1970s-1990s
Drill-Feel
Very soft, crumbly texture, light gray particles
Density
Very Low - 25-35 lbs/ft³
Recommended Anchor
Specialty lightweight anchor or reinforced system
Drill Bit Type
Sharp masonry bit, avoid excessive pressure
Load Capacity
Up to 15 lbs per anchor point
Aerated concrete wall material

Identification Testing Methods

Before drilling, perform these simple tests to confirm your wall type:

  • Visual Inspection: Examine the surface texture, color, and any visible joints or patterns.
  • Sound Test: Tap the wall with your knuckle. Solid materials produce a sharp sound, while hollow spaces create a deeper tone.
  • Magnet Test: Use a strong magnet to locate metal studs behind drywall, which affects anchor selection.
  • Test Drill: Start with a small pilot hole and observe the drill-feel and dust characteristics.