正交胶合木（CLT）是一种风靡全球的新型低碳预制型建材，近十年来，在欧美和日本等发达国家得到了飞速发展。CLT板材轻质高强，具有大幅面特征，双向强度高，同时具有良好的耐火性能，保温隔热效果好，既可作结构材也可作装饰材使用，预制装配性好，装拆方便，材料也可完全回收利用，满足了装配式建筑绿色低碳及节能环保的要求。但现有技术中CLT主要用于建筑物的墙板、楼板的搭建，或直接用于搭建屋盖，通常需要与复杂的梁柱配合使用，这样就增加了施工的复杂性和建筑造价，同时建筑型式和屋盖结构呆板，缺乏变化和美观性。
我司新近研发成功了一种新型的CLT节能组合屋盖，已申请并获得国家专利（ZL202220885336.0）。该节能组合屋盖是在钢筋混凝土梁/墙体或钢架上铺设CLT板材作为主体承重构件，再在CLT板材上构建轻型木桁架和屋面防水结构而形成。这种组合结构有助于打造三角形或弧形等屋顶坡面，创造出各种优美的屋顶轮廓。
Cross-Laminated Timber (CLT) is a revolutionary low-carbon prefabricated building material that has gained global popularity. Over the past decade, it has experienced rapid development in developed regions such as Europe, North America, and Japan. CLT panels are lightweight yet strong, characterized by their large format and high biaxial strength. They also exhibit excellent fire resistance, thermal insulation, and can be used both as structural and decorative materials. With superior prefabrication and assembly properties, easy installation and disassembly, and full recyclability, CLT meets the requirements of green, low-carbon, energy-efficient, and environmentally friendly prefabricated construction.
However, in existing applications, CLT is primarily used for building wall panels, floor slabs, or directly for roof construction, often requiring complex beam-column systems for support. This increases construction complexity and costs, while also limiting design flexibility and aesthetic appeal in architectural forms and roof structures.
Our company has recently developed an innovative CLT Energy-Efficient Composite Roof System, which has been granted a national patent (ZL202220885336.0). This composite roof system utilizes CLT panels laid on reinforced concrete beams/walls or steel frames as the main load-bearing components, upon which light wood trusses and waterproof roofing structures are built. This integrated approach facilitates the creation of sloped roofs in various shapes, such as triangular or curved profiles, enabling diverse and aesthetically pleasing roof designs.
应用此节能组合屋盖技术，我司在中加国际产业合作项目支持下完成了中国首个超低能耗CLT混合结构建筑示范小区项目。为探索符合中国国情、性价比高、节能效果好的新型结构型式，该小区建筑采用了钢筋混凝土框架+CLT的混合结构。所采用CLT板材为三层，厚度105mm，平均密度为392kg/m³，导热系数为0.097W/(m×k)，燃烧性能为难燃B1级，耐火极限可达1.5h。此CLT组合屋盖由于CLT优异的隔热性能，加上额外的空气流通层，其屋面平均传热系数k小于0.35W/(㎡×k)，完全达到夏热冬冷地区超低能耗建筑的要求(GB/T51350-2019《近零能耗建筑技术标准》)，建筑能耗水平也较现有国家标准降低30%以上。在建筑运营过程中或全生命周期内的节能减排效果将更加明显。此外，此组合屋盖的CLT板材底面可直接暴露，呈现出天然木材的美感和优良的装饰效果，可免除复杂的吊顶制作和装修，实现屋盖结构、保温、防水和装修等作业的一体化，节约了装修工时和成本。
此CLT组合屋盖搭建快速，施工方便，CLT板材和轻型木桁架都可进行工厂预制，现场组装，可大大节省施工周期，性价比高，提高了建筑的承重、保温隔热、防火及美学等综合性能；它不但适用于各类新建的超低能耗木结构和混合结构建筑，而且适用于各类旧有房屋的节能改造，因此具有很好的推广应用前景，可助力中国碳中和目标的实现。
Application of this energy-efficient composite roof technology has enabled our company to complete China's first ultra-low energy consumption CLT hybrid building demonstration community project, supported by the China-Canada International Industrial Cooperation Program. To explore a new structural approach that aligns with China's context, offers high cost-effectiveness, and delivers exceptional energy-saving performance, the community buildings adopted a hybrid system combining reinforced concrete frames with CLT panels. The CLT panels used consist of three layers with a thickness of 105 mm, an average density of 392 kg/m³, a thermal conductivity of 0.097 W/(m·K), a flame-retardant classification of Class B1, and a fire resistance rating of up to 1.5 hours.
Thanks to the excellent thermal insulation properties of CLT and the inclusion of an additional air circulation layer, the average heat transfer coefficient (K-value) of the roof system is less than 0.35 W/(m²·K). This fully meets the requirements for ultra-low energy consumption buildings in regions with hot summers and cold winters, as specified in the national standard GB/T 51350-2019 (Technical Standard for Nearly Zero Energy Buildings). The building's energy consumption level is also more than 30% lower than existing national standards. The energy-saving and emission-reduction effects will be even more significant during the building's operational phase or throughout its entire life cycle.
Additionally, the underside of the CLT panels in this composite roof system can be left exposed, showcasing the natural beauty of wood and providing an elegant decorative effect. This eliminates the need for complex ceiling installations and finishes, integrating roof structure, insulation, waterproofing, and decoration into a single process. This approach saves both construction time and costs.
The CLT composite roof system is quick to install and easy to construct. Both the CLT panels and the lightweight wood trusses can be prefabricated in factories and assembled on-site, significantly reducing construction timelines. With its high cost-effectiveness and enhanced comprehensive performance in load-bearing, thermal insulation, fire resistance, and aesthetics, this system is not only suitable for various new ultra-low energy consumption wood and hybrid structures but also ideal for energy-efficient retrofits of existing buildings. As such, it holds strong potential for widespread adoption and can contribute to achieving China's carbon neutrality goals.
