Exterior joinery: managing the building's energy performance

Why is exterior joinery a lever for energy performance?

Exterior joinery constitutes a sensitive point of thebuilding envelopeThey ensure the transition between interior and exterior, while also participating in the management of thermal, light and acoustic flows.

In older buildings, they are often responsible for significant heat loss. Replacing them is therefore an effective way to improve overall performance, provided it is integrated into a coherent approach.

High-performance joinery allows for:

• to limit heat loss in winter
• to control solar gain in summer
• to improve acoustic comfort
• to improve airtightness

"High-performance joinery does not compensate for poor insulation, but it optimizes the entire system."

Definition and role of exterior joinery in the building envelope

Exterior joinery encompasses all the elements that ensure the building's enclosure: windows, doors, shutters, and bay windows. It contributes directly to the thermal performanceto safety and aesthetics.

Their role is multifaceted and cross-cutting in a construction or renovation project.

Thermal and acoustic insulation

The joinery participates in the reduction of energy lossesThe glazing and the performance of the frame directly influence heating and air conditioning consumption. Good thermal insulation reduces heating and air conditioning consumption, thus guaranteeing energy savings. The glazing and the quality of the frames play a decisive role in this area.

The soundproofing becomes essential in urban or exposed environments. The choice of glazing and the quality of installation determine the level of comfort.

Security and burglary resistance

Openings are sensitive access points. Securing them relies on:

• multipoint locks
• laminated glazing
• certified systems

These elements are particularly important on the ground floor or in professional premises.

Comfort and brightness

Window and door frames influence natural lighting. The light transmission factor (TLw) and the solar factor (Sw) determine the amount of light and heat entering the building.

Architectural harmony

The materials, colors, and finishes contribute to the building's identity. The joinery must integrate with the existing architectural style.

What are the main types of exterior joinery?

Exterior joinery comes in several families, each with its own technical specifications and performance.

Windows: ventilation, light and insulation

The windows ensure natural lighting, ventilation and thermal and acoustic insulation of buildings. Their design must meet climatic constraints and the specific needs of occupants.

The main types of openings

• Swinging or French style: traditional inward opening.
• Tilt and turn: dual function of full opening or tilting for ventilation.
• Sliding: ideal solution for large openings.
• Fixes: optimize the supply of light.

The most common materials

• PVC: practical and economical, minimal maintenance.
• Wood : warm and ecological, requires regular maintenance.
• Aluminum: Modern and robust, perfect for large spaces. Requires thermal breaks for good insulation.
• Mixed wood-aluminum: high-performance alliance between aesthetics and durability.

The main types of glazing

• Standard double glazing: two glasses separated by argon gas.
• Acoustic double glazing: different thicknesses for sound insulation.
• Triple glazing : three glasses for maximum thermal insulation.
• Laminated glazing: glasses assembled with a PVB film for safety.

Exterior doors: security and insulation

The front door combines security, insulation, and aesthetics. It is available in several versions:

• Materials : wood, steel, aluminum, PVC or mixed wood-aluminum…
• Security: multi-point locks (3 to 7 points), armoring, laminated glazing, etc.
• Insulation: thermal break threshold, insulating panels, etc.

Models vary from traditional to contemporary, with solid, glazed or semi-glazed versions.

Shutters: thermal and solar protection

The shutters also ensure the thermal and solar protection of the buildingThey reinforce insulation in winter and limit overheating in summer.

Main types of shutters

• Swinging shutters: traditional materials (wood, PVC, aluminum), solid or louvered versions, classic style.
• Roller shutters: integrated trunk, possible motorization, good protection and insulation.
• Adjustable sun blinds: adjustable slats to manage light and heat, contemporary design.

Gates: access and security

The gate is the primary element of security and welcome to a property. It demarcates access while affirming the architectural style of the whole.

The main types of opening

• Beaters: classic opening with one or two leaves, generally opening inwards.
• Sliding: side opening along a rail, ideal solution for tight spaces or sloping entrances.

The most common materials

• PVC: economical and easy to maintain, very weather resistant.
• Aluminum: modern, light and stainless, allows for varied designs and large dimensions.
• Wood : warm and natural aesthetic, requires regular maintenance (stain, paint).
• Steel or wrought iron: very robust and secure, offers a traditional or contemporary style, essential anti-corrosion treatment.

Customization and security options

• Filling: full for total blackout, openwork for brightness or semi-full for an aesthetic compromise.
• Motorization: automation for optimal user comfort, with remote control or connected system.
• Access control : integration of intercom, videophone or digital code to secure the entrance.
• Matching gate: creation of a separate pedestrian access, harmonized with the style of the gate.

Bay windows: light and continuity between interior and exterior

Bay windows provide maximum natural light and create visual continuity between the interior and exterior. They must combine aesthetics, thermal comfort, and sound insulation to ensure a pleasant living environment.

Fixed bay windows

• They do not open, which allows for a large glass surface for optimal lighting.
• Thanks to their design, the risks of heat loss are limited.
• They are particularly suitable for areas where you want to promote brightness without needing an opening.

Sliding glass doors

• They promote smooth circulation between the interior and exterior thanks to their lateral opening.
• Their sliding system avoids clutter, ideal for small spaces or terraces.
• They can be equipped with different options (motorization, integrated roller shutters) for greater ease of use.

Thanks to their large glass surfaces and their insulation performance, fixed and sliding bay windows are a preferred choice for optimizing brightness and creating a harmonious link with the outdoors.

How to evaluate the performance of exterior joinery?

Exterior joinery is evaluated according to three essential criteria. Their actual performance depends on the installation quality and thejoint sealing.

Thermal insulation

L'thermal insulation The value of a carpentry workshop is assessed on two levels:

• The glazing alone, characterized by the coefficient Ug : double glazing with argon reaches Ug ≈ 1,1 W/m²K, triple glazing reaches Ug ≈ 0,5 W/m²K.
• The entire window (frame + glazing + spacer), characterized by the coefficient Uw : the common values ​​are Uw ≤ 1,3 W/m²K, or Uw ≤ 1,0 W/m²K for the passive building.

Doors are characterized by their thermal transmission coefficient Ud (in W/m²K). The lower this value, the higher the insulation performance. Roller or hinged shutters enhance insulation: a PVC or aluminum shutter reduces losses by 5 to 15%, a shutter with insulated slats reaches 20%.

Soundproofing

Sound insulation is measured in decibels (dB). An index Rw of 30-32 dB suitable for quiet environments. In urban areas or near major roads, the glazing must reach Rw ≥ 40 dB. Near airports or railways, a Rw ≥ 45 dB becomes necessary.

Le asymmetrical glazing (6-16-4) attenuates certain frequencies, while the acoustic laminated glazing (44.2) allows for more homogeneous insulation. The ACOTHERM certification (AC1 to AC4) attests to a reduction of 28 to 40 dB, subject to careful installation and suitable joints.

Weather resistance (AEV classification)

This classification evaluates the resistance of the carpentry according to three criteria:

• Air permeability (A): scale from 1 (poor) to 4 (excellent),
• Watertightness (E): scale from 1 (low) to 9 (high exposure),
• Wind resistance (V): scale from 1 to 5 (pressure) and A to C (deformation).

These laboratory tests allow you to select the right joinery for your exposure. Windy or humid areas require high classifications (e.g. A4 E9A V4C) to ensure long-term watertightness.

Safety and standards

The safety of joinery is based on several certifications and standards.

Certification of locks

The certification A2P allows you to assess the resistance of locks to burglary. It offers different levels of protection, with particular attention paid to the main access points and sensitive points of a building. 

Certification of glazing

The certification Cekal guarantees the quality and performance of different types of glazing:

• Insulating glass, attesting to their thermal and acoustic performance,
• Laminated glazing, evaluated for their safety, durability and sound attenuation properties,
• Tempered glass, certified according to their specific usage.

European standards

Two European standards govern the safety of joinery: 

• EN 356: defines the levels of protection of glazing, with classes ranging from P1A to P8B (from burglar-resistant to bulletproof).
• EN 1627: joinery resistance standards (RC1 to RC6).

When and why should you replace your windows and doors during an energy renovation project?

Replacing windows and doors is usually part of a comprehensive renovation strategy. It must be coordinated with other work.

Typical situations:

• single glazing
• air infiltration
• thermal discomfort
• noise

The correct order of work consists of:

• treat the insulation
• then replace the joinery
• adjust the ventilation

Poor coordination can lead to problems, particularly those related to humidity.

What architectural and regulatory constraints govern exterior joinery?

Exterior carpentry shapes the architectural appearance of a buildingThey must comply with the urban planning regulations defined by the PLUCurrent materials offer numerous possibilities for customization thanks to their finishes and colors.

Finishes according to materials

• Le  wood comes in natural finishes with stain or in paint shades.
• Le PVC offers different colors and wood imitations, suitable for traditional constructions.
• L'aluminum material stands out for its thermo-lacquered, textured or matte finishes, with two-tone option.
• Mixed joinery wood-aluminum combine the warmth of wood inside and the strength of aluminum on the facade.

 entrance doors incorporate decorative glazing and two-tone finishes, harmonizing with classic and contemporary architecture.

Urban planning constraints

The integration of joinery is governed by regulatory constraints. Local Urban Planning Plan may impose specific colors and materials, prohibit certain components such as PVC, or require compliance with the original proportions.

In protected areas, particularly near historic monuments, modifications require the agreement of the Architect of Buildings of FranceThis regulation preserves heritage by favoring traditional solutions, such as the use of wood.

What innovations are transforming exterior joinery?

La automation and Eco conception are transforming the joinery sector, combining improved comfort and respect for the environment.

Home automation and connected joinery

The joinery is integrated into the building's intelligent systems:

• Motorized roller shutters become automated : night programming, gradual awakening, or even adaptation to the weather via sensors.
• The windows incorporate innovative technologies : photovoltaic cells for electricity production, electrochromic glasses regulating brightness and heat.
• Security is enhanced by connected functions : remote control by smartphone, break-in detection, biometric recognition, etc.

Smart windows

• electrochromic glazing
• photovoltaic integration

Eco-design and performance

The sector is developing ecological solutions. Wood, FSC or PEFC certified, benefits from natural treatments for its durability. PVC incorporates up to 70% recycled material in its profiles, while aluminum reaches 95% recyclability.

Glazing also shows significant progress. new generation triple glazing achieves a Ug ≤ 0,6 W/m²K thanks to rare gases and warm edge interlayers. Phase change films represent a major innovation, storing daytime heat to release it at night.

Exterior joinery They constitute a key lever in the energy performance and comfort of the building. Their selection and implementation must be part of a comprehensive approach, integrating the building envelope, ventilation, and energy systems to guarantee sustainable and consistent results.

Solutions exterior carpentry are supported by an ecosystem of manufacturers, of manufacturers and specialist networks, which are constantly innovating to meet the requirements of energy performance, sustainability and comfort, in a context of profound transformation of the building sector.

Text written and documented by batipole.com, a media outlet for professionals in the building, housing and real estate sectors.