Building cladding terms
plainly defined

An almost entirely mineral ACP core with no significant organic content, classified A2-s1,d0 under EN 13501-1, meaning it does not contribute significantly to a fire. The customary specification on towers, public buildings, hospitals and schools. Costs 10 to 18 percent more than FR at panel level.

when regulation requires A2

A cladding panel made of two thin aluminum skins bonded either side of an inner core. The core determines the panel’s reaction-to-fire classification, and therefore which buildings it may be used on. Alucobond, Reynobond and Alpolic are brands in this category.

PE, FR and A2 cores compared

Brand name for an aluminum composite panel (ACP) built from two 0.5 mm aluminum skins coated in PVDF over an inner core 3 or 4 mm thick. Finished panel thickness is 4 or 6 mm and weight is 5.5 to 8 kg/m². In Israel the name is used generically for any ACP panel, although it is a specific brand.

the complete Alucobond cladding guide

Large-format dense ceramic panels installed as rainscreen cladding on a support system. Non-combustible (A1 or A2) and highly resistant to wear and staining, but heavy at 25 to 35 kg/m² and relatively brittle under impact. Costs a project-specific figure.

facade material comparison

A document listing every component in the project with its quantity and unit price. In facade cladding a proper bill of quantities separates panels, support system, insulation, fire stops, access and labour. A quote that resolves to a single figure with no bill of quantities cannot be compared against another quote.

how to read a cladding quote

Building Information Modeling. Three-dimensional modeling of the facade integrated into the project model. It allows clash detection against HVAC, electrical and plumbing before fabrication, plus per-panel shop drawings and an accurate bill of quantities. A clash found in the model costs an hour of design time; the same clash found on the scaffold costs a week.

A classification expressing a building’s energy efficiency, from A and above (efficient) down to lower grades. The building envelope, including the facade and its insulation, is one of the strongest influences on the rating. A rear ventilated facade with mineral insulation improves it substantially.

how much energy an insulated facade saves

A cladding panel whose edges are folded back to form a rigid tray, hung on the support system with no fasteners visible on the panel face. Cassette fixing produces a clean facade with hidden joints and costs more than rivet fixing because of the additional fabrication hours.

A non-combustible component fixed inside the facade cavity to block the passage of flame and smoke. Fire stops are installed at every floor level, around every opening, at the base and at roof line. Without them the ventilated cavity itself becomes a vertical fire path, which is a primary cause of facade failure in fires.

fire stop requirements

Computer Numerical Control. Automated cutting and folding that produces cladding panels to millimetre precision. In facade work CNC enables sharp folded corners, hidden joints, cut logos and decorative perforation.

A glazed envelope system hung from the building frame that carries no structural load other than its own weight and wind load. Common on office towers, and usually combined with Alucobond cladding on solid facades, service cores and plant floors.

aluminium cladding systems for office buildings

Separation of the aluminum skins from the core of an ACP panel, caused by bond failure, water ingress at an unsealed edge, or prolonged exposure to high temperature. A delaminated panel has lost its rigidity and integrity and must be replaced.

The European standard for classifying the reaction to fire of construction products. It grades materials from A1 (no contribution to fire) down to F, with two supplementary measures: s for smoke production (s1 to s3) and d for flaming droplets (d0 to d2). This classification appears on every cladding panel’s manufacturer certificate.

A standardised document setting out a product’s environmental impact across its life cycle, including embodied carbon and recycled content. On projects pursuing LEED or green building certification, the panel manufacturer’s EPD is a required document.

A licensed professional who sets the fire safety requirements for a specific project with the local authority and the national Fire and Rescue Authority. In facade cladding they determine which core grade is required and how fire stops are detailed, and their sign-off is needed for occupancy approval.

An ACP core in which roughly 70% of the material is mineral fire-retardant filler. Typical EN 13501-1 classification is B-s1,d0. This is the standard specification for residential, office and commercial buildings that are not classified as high-rise. The grade for a given project is set in the project specification.

the difference between FR and A2

Accelerated corrosion that occurs when two dissimilar metals are in contact in the presence of moisture, consuming the more reactive metal. In facade cladding this is why fixings and profiles must be matched in material and grade, particularly in coastal areas where salt accelerates the process.

A cladding panel made from resin-impregnated paper layers compressed under high pressure and heat. Costs a project-specific figure, weighs 8 to 12 kg/m² and lasts 15 to 20 years. Its reaction-to-fire classification is lower than that of an A2-core ACP.

The Israeli standard for thermal insulation of buildings. It sets minimum envelope insulation values and in practice requires an insulation layer in the facade for new construction and substantial additions. The practical way to comply is a rear ventilated facade with 80 to 120 mm of mineral wool.

facade insulation and energy savings

The Israeli standard for reaction to fire of building materials. It classifies the material, using a methodology parallel to EN 13501-1, and in facade cladding it is the basis for determining the panel core grade. Important: the standard classifies the material, while the grade for a given project is set in the project specification.

what code 921 actually requires

The difference between the panel area ordered and the net facade area, caused by cuts, folds and offcuts. On a simple rectangular facade the waste factor is low. On a facade with deep window reveals, curves and many cuts it reaches 15 to 25 percent, and it is one of the main reasons two projects of the same area price differently.

what moves cladding cost per square metre

A non-combustible insulation made from spun molten rock. Typical thickness in a ventilated facade is 80 to 120 mm, giving R-3 to R-5 thermal resistance plus 10 to 15 dB of acoustic attenuation. It is the only insulation suited to a ventilated cavity — polystyrene (EPS) is combustible and voids system compliance.

A slight waviness visible across a flat metal panel, most noticeable in raking light. It is caused by internal stress in the material, over-rigid fixing, or thermal expansion with insufficient joint clearance. It is not a structural defect, but it is the most common aesthetic defect in metal cladding, and it is prevented by correct joint and fixing design.

The designed gap between two adjacent panels. The joint absorbs thermal movement of the aluminum, accommodates fabrication and installation tolerances, and forms part of the water management strategy. An open joint drains into the ventilated cavity; a closed joint is sealed with a profile or gasket.

An ACP core made of pure polyethylene. Polyethylene is combustible, so PE panels are not suitable for the facade of any occupied building. Regulation worldwide and in Israel tightened after the 2017 Grenfell Tower fire. DAR GROUP does not offer or install PE panels.

why PE left the market

Polyvinylidene Fluoride. A fluoropolymer coating baked onto the aluminum skins that holds colour and resists UV, humidity and salt air for 20 years or more. PVDF fades evenly rather than in patches, unlike cheaper polyester coatings which fade unevenly within 5 to 8 years.

A European colour standard in which every shade carries a four-digit code. On a cladding project, specifying the colour by RAL code is the only way to define it contractually. A verbal description such as "dark grey" is not enforceable.

choosing colours and finishes

An installation system that holds the cladding panels away from the structural wall, creating a continuous 40 to 80 mm air cavity between them. The cavity drains moisture, removes heat by natural convection and makes room for an insulation layer. The result is a 20 to 35 percent reduction in cooling load and a facade that lasts 25 years or more.

how a rear ventilated facade works

A detailed drawing produced by the installing contractor showing every panel, profile and connection detail as it will actually be built, as distinct from the architect’s drawing which shows design intent. Approval of shop drawings by the architect and engineer is the point at which dimensions and details are frozen before fabrication.

The assembly of rails and brackets that carries the cladding panels and transfers their weight and wind load into the structural wall. In a compliant system it is aluminum or stainless steel, sized for the site wind load, and anchored into the structure with engineered fixings rather than into render.

A powered cradle hung from the roof that allows facade work without erecting scaffolding from ground level. On tall buildings it is cheaper and faster than fixed scaffolding, but it limits how much material can be lifted at a time and how many workers can occupy one section.

An Israeli national plan for retrofitting existing buildings against earthquakes, which developed into urban renewal tracks for seismic strengthening (38/1) and for demolition and rebuild (38/2). In both tracks the facade is rebuilt, which makes it the natural moment to fix a quality cladding specification — before signing with the developer.

facade upgrade in urban renewal projects

A localised path where heat crosses the envelope faster than through the surrounding area, usually through a conductive element such as a metal bracket, beam or column. Thermal bridges reduce the benefit of insulation and create cold spots where condensation and mould can develop. Modern support systems use thermal breaks to limit them.

A composite of wood fibre and polymer that reads as timber but needs no oiling or painting. Used mainly as an accent on villa facades rather than as a whole envelope. Its reaction-to-fire classification is lower than aluminum and should be checked against the project requirement.