Building Materials in
Structural Engineering
A guide to the most common materials used in construction — their properties,
applications, and the engineer's role in specifying them.
Why Material Selection
Matters
Every structural decision begins with material selection. The right choice balances
cost, strength, durability, and constructability — directly influencing a building's
safety, performance, and lifespan.
Weight
Affects foundation design and seismic response
Strength
Determines load-carrying capacity
Durability
Impacts long-term maintenance and lifecycle
Cost
Drives project feasibility and budget
Two Categories of Building Materials
Natural Materials
Sourced directly from the earth — stone,
timber, and earth-based materials. These
have been used for millennia and often
require minimal processing, though they
typically need treatment or preparation
before structural use.
Man-Made Materials
Engineered and manufactured — concrete,
steel, and masonry units. Produced to
consistent, standardized specifications,
offering predictable performance and
widespread availability across the industry.
Quality Standards &
Manufacturing
The production of structural-grade materials is governed by national standards
and rigorous quality control — ensuring reliability and consistency across every
project.
01
02
Raw Material Sourcing
Manufacturing & Testing
Suppliers must meet ASTM, ACI, AISC, or
Inspection and lab testing verify
equivalent standards
strength, composition, and dimensional
tolerances
03
Certification & Documentation
Mill certificates, test reports, and compliance documentation accompany delivered
materials
The Engineer's Role in Material Specification
Writing the Specifications
A critical responsibility of the structural
engineer is preparing project specifications
— defining the quality, properties, and
applicable standards for every material used.
Specify material grades, strengths, and
testing requirements
Reference applicable codes: ACI, AISC,
NDS, ASTM
Collaborate with clients on cost vs.
performance trade-offs
Review and approve material submittals
before construction
Clear, thorough specifications
reduce risk, avoid substitutions,
and protect the integrity of the
design.
Concrete & Steel
Two foundational materials shaping the built environment — from footings to
skyscrapers.
What Is Concrete?
Composition
Cement + aggregates (sand, crushed
stone) + water
Mix Design
Properties depend on ratios — suppliers
provide test results per batch
Versatility
Poured into any formwork shape;
hardens into stone-like material
Concrete: Strength, Curing & Applications
Day 4–7
Major strength
development
Day 7+
Day 1–3
Full design strength;
prevent cracking
Initial set; keep moist
Proper curing over 7 days is essential to prevent cracking and ensure full capacity.
Compression Strength
Key Limitation
Excellent under compressive stress — ideal for foundations
Brittle with limited tensile strength — requires reinforcement for
most structural uses
Reinforced Concrete
Steel rebar compensates for concrete's weak
tensile capacity, creating a composite material
suited for demanding structures.
Tall Buildings
Bridges
Roads & Tunnels
Structural Steel
High Strength-to-Weight
Ratio
Ideally suited for tall buildings and
large industrial facilities
Standard Shapes
Angles, I-beams, C-channels — welded
or bolted for efficient connections
Fast Installation
Less time-consuming than concrete;
installable in any environment
Steel: Cost & Optimization
Engineer's Responsibility
Select economical sizes and shapes based on actual loads — avoid
overdesign.
Client questions about member size can often be
addressed through load reduction or added supports.
Wood as a Building Material
Timeless, renewable, and versatile—wood has powered construction for
millennia. Durable when maintained; performs well for homes and
residential buildings.
Dimensional Lumber & Timber
Common sizes: 2"x4", 2"x6" — note: actual = 1½" x 3½"
Used for walls, floors, studs, joists
Larger cross-sections called timber/beams for heavy frames and
bridges
Lightweight and highly machinable — easy to cut, nail, and fasten
Tip: verify nominal vs actual dimensions when planning materials.
Engineered Wood Types & Benefits
Plywood
Glulam
Fiberboard & OSB
Layered veneers for
Glued laminated beams —
Cost-effective, uniform
strength and dimensional
long spans and heavy
panels for sheathing,
stability; great for
loads with engineered
furniture, and finishes.
sheathing and subfloors.
predictability.
Engineered wood: tailored performance, predictable strength, and efficient use of raw material.
Masonry as a Structural
System
- Individual units (concrete block, brick, stone, glass block) joined with
mortar - Excellent compression strength → ideal for load-bearing walls Durable and fire-resistant; quality depends on mortar & workmanship
Reinforcement & Strength
Stacking for
Height
Grouted Cores
+ Rebar
Compression
Behavior
Walls can be
Fill voids with
Masonry excels in
stacked for multi-
grout and vertical
compression but is
story loads; lower
steel — more bars
weak in tension;
walls carry
+ closer spacing =
design for axial
cumulative weight.
higher capacity.
loads and stability.
Openings & Load Paths
- Windows/doors require horizontal spanning elements
(lintels or beams)
- Masonry less flexible for large
openings than steel or concrete framing
- Economical
when openings and wall segments are moderate in size
Ensure lintels or transfer beams are detailed to carry
masonry loads over openings.
Practical Design Considerations
Foundation &
Transfers
Workmanship &
Mortar
Coordination
Provide continuous
Mortar quality and skilled
openings, reinforcement,
bearing to foundations;
masonry work are critical
and lintels early to avoid
use transfer beams where
to durability and
costly changes.
walls cannot bear directly.
serviceability.
Coordinate floors,
Key takeaway: Use reinforced, grouted masonry where compression dominates; combine with concrete/steel for large openings
or long spans.
Other Construction Materials
— Practical Overview
Quick guide for homeowners, architecture students, and entry-level builders
Engineered Wood — What & Where
Laminated &
Composite Products
Common Uses
Key Properties
Exteriors, interiors,
Engineered for: cost
Wide family: LVL, OSB,
flooring, roofs, load-
efficiency, improved
plywood, CLT — tailored
bearing panels, decorative
strength, rot resistance,
strength and cost
elements
consistency
Tip: Choose product by structural rating and moisture resistance, not just price.
Bamboo — Fast‑growing,
strong, versatile
Bamboo = grass with wood-like performance. Rapid
renewability makes it attractive for sustainable builds.
Uses
Performance
Sustainability
Scaffolding, small structural members,
Higher compressive & tensile strength
Fast growth (some species ~1.5 in/hr) —
flooring, cabinetry
than many woods; very lightweight
lower embodied carbon when sourced
responsibly
Glass — Light, view, and performance
Durable but brittle. Chosen for optical qualities: transparency,
translucence, reflectivity.
Thermal Options
Insulated (double/triple glazed), low‑E coatings for energy
control
Safety & Strength
Tempered, laminated options improve impact resistance and
post-breakage behavior
Optical Control
Tints, frits, and coatings for glare, privacy, and solar heat gain
management
Make photos realistic: verify edge detail, reflections, and
appropriate context for material selection.
Common Building Materials:
Plastic · Foam · Plaster
Practical overview for homeowners, architecture students, and entry-level
builders
Plastic — versatile & affordable
Common uses
Key properties
Design notes
pipes, siding, windows,
inexpensive, lightweight,
wide variety of finishes;
doors, flooring, interior
durable; flammable;
choose UV-stable grades
panels
temperature sensitive
for exterior use
Use corrosion‑resistant connectors and allow for thermal expansion
Foam — lightweight thermal &
acoustic solution
Foams contain trapped air or gas pockets — available as rigid boards, loose
fill, or spray-applied
Uses
Properties
Installation tips
insulation, sound dampening,
very lightweight, high R-value
seal gaps for air control; follow
fire‑barriers (treated)
per inch, variable compressive
manufacturer for flame‑retardant
strength
treatments
Plaster — finish & protection
Materials
Uses
Properties
gypsum, lime,
interior walls,
easily worked and
cement, clay
ceilings, decorative
finished; not
moulding,
structural; repairs
fireproofing
are straightforward
Protect plaster from impact and moisture; use appropriate
substrate and lath
Choosing the Right Material — Quick
Checklist
Function
thermal, moisture, finish, structural? pick material that matches the
function
Durability & Safety
consider fire performance, UV stability, temperature limits
Installation
skills, tools, compatibility with adjoining materials
Maintenance
repairability, lifespan, recyclability
For complex assemblies, consult product datasheets and local codes.
0
