Saint Gobain : Half Year Financial Report 2023 -

Half-year financial report 2023

Including:

• Half-yearmanagement Report 2023
• Condensed consolidated Financial Statements as of June 30, 2023
• Statutory Auditors' review report on the 2023 half-year financial information
• Statement by the persons responsible for the 2023 interim financial report

This English-language version of the Half-Year Financial Report 2023 is a free translation of the original French version of the Half-Year Financial Report 2023 made available on the Company's website. It is not a binding document. In the event of a conflict of interpretation, reference should be made to the French version which is the authentic text.

Compagnie de Saint-Gobain

Tour Saint-Gobain • 12, place de l'Iris • 92400 Courbevoie • France • Tél. [phone] • www.saint-gobain.com

S.A. au capital de € 2 055 672 256 • 542 039 532 R.C.S Nanterre • APE 7010 Z

PRESS RELEASE

July 26, 2023 6:00pm

Further record results in H1 2023

2023 outlook upgraded

• Record margin of 11.3% and record operating income of €2,813m despite a difficult environment
• Significant operating income growth in North America, Asia and emerging countries, which represent over 60% of the Group's earnings
• Strong increase in free cash flow, up 30% at €2,192m
• Double-digitoperating margin expected in full-year 2023 for the third consecutive year, demonstrating the Group's resilience

Benoit Bazin, Chief Executive Officer of Saint-Gobain, commented:

"In a difficult macroeconomic environment, the Group once again demonstrated the effectiveness of its "Grow & Impact" strategy and the resilience of its decentralized operating model. Thanks to our teams' agility, entrepreneurial spirit and dedication, we once again delivered record earnings, margins, and value creation in the first half of 2023. Our organization by country has enabled the Group to outperform, both by proactively adapting our operations on the ground but also by making selective growth investments, including in additional production capacity and with acquisitions such as Building Products of Canada.

Over 60% of our earnings are now generated in North America, Asia and emerging countries, where trends are improving and the growth outlook is supported by demographics and rapid urbanization. In Western Europe, renovation - our biggest market - continues to show good resilience as expected, with stimulus measures and regulations aimed at accelerating the path to carbon neutrality; structural demand for new construction is growing, even though additional financing costs are temporarily impacting the sector.

Despite a moderate slowdown in its markets in the short-term, in 2023 Saint-Gobain will deliver a double-digit operating margin for the third consecutive year. Over the medium term, I am confident that the Group's new profile places it firmly on a sustainable profitable growth trajectory."

Saint-Gobain

Tour Saint-Gobain • 12 place de l'Iris • 92400 Courbevoie • France • Tel. [phone] • www.saint-gobain.com

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Saint-Gobain continues to outperform its markets thanks to the pertinence of its strategic positioning at the heart of energy and decarbonization challenges, and to the strength of its local organization by country, which enables it to offer comprehensive solutions to its customers.

A comprehensive range of solutions accelerating growth

Saint-Gobain's solutions for renovation, the building envelope and innovative new light construction methods drastically reduce CO2 emissions while increasing user wellbeing (thermal and acoustic comfort, light, air quality and hygiene). Each country CEO has adopted a specific local approach:

• In France, "Saint-Gobain Solutions" is organized by market and provides comprehensive offers for commercial buildings, educational and healthcare facilities, and multi-family housing (social housing associations, developers and condominiums).
  As the leading player in the value chain, Saint-Gobain organized the first "Sustainable Construction Talks" in Paris on July 4, 2023 on the theme "Global and sustainable renovation: why and how to accelerate?", which followed the publication in April of the first international Barometer on the transformation of construction. The Group also showcased its comprehensive range of solutions in three "white papers" published during the first half of the year on educational and healthcare facilities and on the renovation of multi-family housing.
  Thanks to these efforts, the Group is capturing market share on major building projects with environmental certification (HQE, BREEAM, LEED, BBC Effinergie, NF Habitat), where the value of our comprehensive offers is approximately twice as high as for traditional projects. The current renovation of Le Carré des Invalides in Paris featuring 10 Saint-Gobain solutions is an excellent example of such sustainable and low-carbon construction.
• In Poland, the "Saint-Gobain Solutions" organization set up at the end of 2022 and bringing together all local brands, encourages the development of systems and cross- selling in key segments such as premium multi-family housing, sports complexes, and educational and healthcare facilities. During the first half of 2023, the "Copernican Revolution Lab" for innovation was unveiled in Warsaw. It features numerous solutions developed by the Group: Isover insulation, Rigips plasters, Weber mortars, Ecophon ceilings and Vetrotech fire-resistant glazing. The Group is also set to launch a digital tool that will allow developers to build housing from prefabricated components using Saint-
  Gobain's comprehensive solutions.
• In India, Saint-Gobain is enhancing its proximity to the end customer with a network of soon 100 "MyHome by Saint-Gobain" showrooms for consumers. For multi-family housing, Saint-Gobain is offering a comprehensive solution as part of the "Modern Homes" program, which features solutions based on glass (windows, balconies, shower doors), plaster and plasterboard (ceilings, interior walls), and construction chemicals. Thanks to this global solutions-based approach, the Group has captured market share, notably winning bids on 35 major non-residential projects. The "Central Vista" mega-project in New Delhi is testimony to these efforts, with 11 Saint-Gobain solutions used.
• In Mexico, a central specification team promoting our comprehensive offer is accelerating sales synergies between products (glass, plasterboard, glass wool, construction chemicals), with 50 multi-solution and façade projects in the first half (versus 64 projects for the whole of 2022). The brand-new Waldorf Astoria hotel in Cancun, for example, brings together the Group's light construction solutions. Lastly, in early 2023, Mexico launched a consulting service recommending Saint-Gobain's solutions to homebuilders.

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A sustainable, innovative offer

Innovation at Saint-Gobain follows five transversal axes:

• Decarbonizing production processes:
• • After achieving the world's first-everzero-carbon (scope 1 and 2) production of glass in 2022, Saint-Gobain delivered another world-first in March 2023, producing glass with a furnace powered by over 30% hydrogen at its Herzogenrath site in
    Germany, which will allow a reduction of up to 70% in direct CO2 emissions (scope 1).
  • The world's first-everzero-carbon (scope 1 and 2) plasterboard production began in April 2023 at Saint-Gobain's Fredrikstad plant in Norway.
  • Saint-Gobainhas raised its internal carbon prices - in force since 2016 - from €75 to €100 per ton for capex investments and from €150 to €200 per ton for R&D projects.
  • The Group uses artificial intelligence (AI) and algorithms to help improve its industrial performance and reduce its energy consumption. In a glass plant, production metrics are analyzed and optimized in real time using data coming from the installation of over 400 sensors.
• Light construction systems:
• • Glasroc® X: the Group has developed a plasterboard reinforced by Adfors fiber glass mat, containing special additives for moisture resistance, making it ideal for external applications. The plasterboard is now manufactured at 23 sites across the globe, and has a carbon footprint two to three times lighter than traditional alternatives.
  • One Precision Assemblies (OPA): in May 2023 in the US, Saint-Gobain launched its first-ever prefabricated residential construction solution for walls, floors, ceilings and roofing.
• Sustainable solutions protecting natural resources:
• • In February 2023 in France, Saint-Gobain launched "Les Engagés", a comprehensive range of sustainable low-carbon solutions including for example Novelio® wall coverings, Isover GR 32 insulation, Placo® Infini 13 plasterboard (with over 50% recycled content), Webercol Flex Eco adhesives (offering a 50%
    reduction in CO2 emissions) and COOL-LITE® XTREME ORAÉ®, which combines ORAÉ® low-carbon glass with high-performance thermally insulating coatings, enabling a 42% reduction in its carbon footprint.
  • Weber mortars continue to replace cement (e.g., with blast furnace slag or fly ash) and sand (with construction demolition materials or excavated earth).
  • Lastly, the Group's February 2023 acquisition of Asphaltica and its asphalt shingle recycling technology for roofing in the US gives added impetus to initiatives promoting the circular economy.
• Materials and solutions to conquer new markets:
• • Ecocem and Saint-Gobain recently announced that they would be partnering to develop and market low-carbon solutions for binders, concretes and mortars.
  • CarbiCrete: at the "ChangeNOW" summit in May 2023, Saint-Gobain announced it had signed a partnership agreement with Canadian start-up CarbiCrete to manufacture cement-free,carbon-sequestering concrete blocks.
  • Development of innovative solutions based on high-performance polymers and ceramics, for example for hydrogen transport and fire-protection for batteries in electric vehicles.

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• Digital tools developed to best serve customers:
• • Artificial intelligence is increasingly being used to deepen our customer knowledge, with marketing segmentation and the introduction of pricing strategies incorporating recommendation-based models to support decision-making.
  • Digital services are available to our professional customers to facilitate their day- to-day and improve their productivity. The TOLTECK app for managing quotes and bills is used every day in France by more than 23,000 trade professionals, while the SOLU+ app makes it possible to easily estimate cost and scale building projects and then send the order to an outlet in just one click. Lastly, the CAP RENOV+ solution simulates over 20,000 renovation projects every month in France, giving value to the associated gains in comfort and energy savings, and integrating the government aid compatible with a given project.
  • Digitalization is an opportunity to provide value-added services all along the value chain. In Vietnam, 4 million QR codes have been printed on products, helping to optimize deliveries and offer a personalized customer experience.
  • An experts' hub of 150 data scientists supports these initiatives.

First-half 2023 once again demonstrated the Group's resilience with a record operating margin of 11.3%.

Like-for-like sales rose 1.6% versus first-half 2022, driven by High Performance Solutions, Asia-Pacific and the upturn in trading in North America. In an environment that remains inflationary, the Group continues to effectively serve and support its customers while managing energy and raw material cost evolution. Prices were up by 7.9% over the period (up 10.2% in the first quarter and up 5.9% in the second quarter, reflecting sequential price stability), owing to price increases implemented last year and certain additional measures taken locally, generating a positive price-costspread overall.

As expected, volumes contracted, down 6.3% over the first half (down 7.0% in the second quarter including a negative working day effect of around 2%), with a moderate slowdown in markets reflecting a contrasting situation: a marked decline in new construction but good resilience overall in renovation. In each local market, the Group is taking the proactive commercial and industrial measures necessary to continue to outperform its markets and maintain its excellent operating performance. Action plans are implemented by country CEOs to adapt to their environment and optimize in real time their P&Ls: commercial efficiency to outperform the market and adaptation of costs where needed (optimization of production capacities, fixed and variable costs and discretionary expenses).

On a reported basis, sales were down by 2.1% to €25.0 billion, with a negative currency impact of 1.4%. The Group structure impact reduced sales by 2.3% and results from the ongoing optimization of the Group's profile, both in terms of disposals - mainly in distribution (UK, Poland and Denmark), glass processing activities, Crystals & Detectors and ceramics for the steel industry - and in terms of acquisitions, mainly in construction chemicals (GCP Applied Technologies "GCP", Impac in Mexico, Matchem in Brazil and Best Crete in Malaysia), exterior products (Kaycan in North America) and insulation (U.P. Twiga in India). The integration of recent acquisitions is progressing well.

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