Glossary
Building materials terms explained.
Construction Chemistry
Chemical products for construction and renovation such as adhesives, coatings, and additives.
Structural Steel
A grade of steel used for load-bearing structures in building and civil engineering construction.
Concrete
Building material composed of cement, water, and aggregates that hardens through hydration.
Concrete Block
A shaped stone made from concrete used for walls, paving, and garden design.
Reinforcement Corrosion
Rust formation on steel reinforcement caused by moisture and chlorides.
Reinforcing Steel
Ribbed steel used for reinforcing concrete structural components.
Bitumen
Binder for asphalt and waterproofing in flat roof construction.
Glued Laminated Timber (GLT)
Adhesive-bonded wood product for large spans in timber construction.
Cross-laminated timber (CLT)
Cross-bonded wood lamellae for solid timber construction.
CLT — Cross-Laminated Timber
Cross-laminated timber: a solid panel material made from perpendicularly laminated layers of boards.
Precast Concrete Element
Pre-fabricated concrete component for rapid assembly on the construction site.
Carbon concrete
Concrete with carbon reinforcement instead of steel, corrosion-free and lighter.
CBAM
EU carbon border adjustment: imports pay the same CO₂ price as domestic production.
CEM I — Portland Cement
Pure Portland cement according to EN 197-1 with at least 95% clinker content. Highest early strength but also the highest CO₂ footprint of all cement types.
CEM II — Portland Composite Cement
Portland cement with 6–35 % blast furnace slag, fly ash, limestone or other supplementary cementitious materials. Reduces CO₂ footprint compared to CEM I by up to 30 %.
CEM III — Blast Furnace Cement
Blast furnace cement with 36–95 % blast furnace slag. Reduces CO₂ footprint by up to 65 % compared to conventional Portland cement.
Concrete Roof Tile
Roof covering made of concrete, dimensionally stable and long-lasting.
Roof tile
Fired clay tile used for covering pitched roofs.
Insulation material
Material for thermal, acoustic, or fire protection insulation of buildings.
DGNB — German Sustainable Building Council
Certification system for sustainable buildings — German alternative to LEED and BREEAM.
DRI Process
Direct reduction of iron ore with reducing gas — alternative to the blast furnace.
Concrete Strength Class
Classification value for the characteristic compressive strength of concrete after 28 days — e.g. C20/25, C50/60.
EPD — Environmental Product Declaration
Standardized environmental declaration according to ISO 14025 / EN 15804 — documents lifecycle carbon footprint.
Epoxy Resin
High-strength synthetic resin used for coatings, adhesive bonding, and injection applications in construction.
EPS (Styrofoam)
Expanded polystyrene, a lightweight and cost-effective insulation material for facades.
ESG — Tempered Safety Glass
Thermally tempered glass with 5 times higher bending tensile strength than standard float glass.
Screed
Leveling layer on structural slabs that serves as a base for floor coverings.
Exposure class
Classification of environmental conditions for concrete components according to DIN EN 206 — determines minimum requirements for cement, w/c ratio, and concrete cover.
Facade plaster
Exterior plaster for protection and design of building facades.
Porcelain Stoneware
A very dense ceramic tile with low water absorption.
Flat Glass
Industrially manufactured glass for windows, facades, and solar installations.
Tile
Ceramic covering for walls and floors in wet areas.
Fly ash (hard coal)
Fine dust from coal-fired power plants, pozzolanic supplementary material in cements. Availability declining with coal phase-out.
g-value
Total solar energy transmittance of glazing — the fraction of solar energy that passes through the glass to the interior.
GEG — Building Energy Act
Central legislation governing energy efficiency requirements for buildings in Germany since 2020.
Drywall
A plasterboard sheet consisting of a gypsum core with cardboard covering used for dry construction.
Granite
Hard igneous rock used for facades, stairs, and work surfaces.
Green Facade
Vegetated building envelope to improve climate and biodiversity.
Green Steel
Steel from nearly emission-free production — via direct reduction with green hydrogen instead of blast furnaces.
Wood fiber insulation
Ecological insulation material made from wood fibers with good heat storage capacity.
Timber Frame Construction
Building method using squared timber with boarded frame construction.
Wood-based material
Umbrella term for chipboard, OSB, MDF and similar board products.
Blast Furnace Slag (GGBFS)
Ground granulated blast furnace slag — a by-product of steel production that exhibits hydraulic binding properties and serves as a grinding addition in CEM II/III cements.
Calcium silicate brick
Masonry unit made from lime and sand, popular for load-bearing interior walls.
KfW Efficiency House
Energy standard levels for KfW funding — KfW-55, -40, -40 NH.
Clinker brick
Hard-fired brick with low water absorption used for façades and paving.
Clinker Factor
The proportion of Portland cement clinker in a cement, expressed as a mass fraction. The primary indicator for carbon footprint.
Structural Timber (KVH)
Technically dried solid wood for load-bearing structures.
Lambda Value (λ)
Thermal conductivity of an insulation material in W/(m·K) — the lower the value, the better the insulating effect.
Electric Arc Furnace (EAF)
Electrically operated melting furnace for steel scrap or DRI iron sponge.
LVL — Laminated Veneer Lumber
Engineered wood product made from glued veneers — enables large spans and slender cross-sections.
Passive House
Building standard with heating energy demand below 15 kWh/m²a.
Paving Stone
Concrete or natural stone unit for traffic surfaces and pedestrian walkways.
PIR / PUR
Polyurethane rigid foam with very low λ-value. PIR is the fire-retardant variant.
Autoclaved Aerated Concrete
Lightweight building material with porous structure and excellent thermal insulation properties.
Portland cement
Most commonly used type of cement, manufactured from limestone and clay.
Sandstone
Sedimentary rock used for façades and restoration of historic buildings.
Slate
Metamorphic rock used for roof coverings and facade claddings.
Prestressed Concrete
Reinforced concrete with pre-tensioned steel reinforcement for increased load-bearing capacity.
Reinforced Concrete
Concrete with embedded steel reinforcement to absorb tensile forces.
U-Value
Thermal transmittance coefficient of a building component in W/(m²·K) — key performance indicator for energy efficiency according to GEG.
UHPC — Ultra-High Performance Concrete
Concrete with compressive strength exceeding 150 N/mm² — enables significantly more slender structural elements and longer spans.
Urban Mining
Existing buildings as raw material repositories — core of circular construction.