238
O. B. Carcassi et al.
and Di Carlo 2010; Lavagna et al. 2018). As a matter of fact, the fossil carbon
emitted by manufacturing of materials and construction might significantly affect
the carbon saving from operational energy (Rovers 2014). The building material
selection strongly affects the overall environmental impact of a building, especially
the selection of the materials for the structural frame and the building envelope (i.e.
basement, exterior walls and roof) on which the former has a major influence (Pal
et al. 2017; Paleari et al. 2016).
The following work presents the results of some studies conducted with the aim of
assessing the benefits, from the point of view of environmental impact, deriving from
the use of bio-based materials as an alternative to conventional building materials
for both new and existing buildings undergoing major renovations.
2 Timber in the Italian Construction Industry
The consumption of forest products has increased in all European regions in the last
20 years, partly supported by public policies which encouraged the use of wood in the
construction and renovation sector through the implementation of energy efficiency
policies (Martín Vallejo 2015).
Reduced times for construction, combined with high-performance expectations,
increased the interest towards prefabricated construction systems. Among these,
wood-based preassembled components are those accounting for the largest growth
in the Italian market, with approximately 2.8% of the housing assets and 8.5% of the
total building stock (Pittau et al. 2016). The picture provided by Centro Studi FederlegnoArredo in their report ‘Rapporto case ed edifici in legno’ suggests a countertrend with respect to the total amount of investments in the construction industry:
starting from 2010, more than 3,000 timber buildings have been built, 89% of which
are residential (Gardino 2015). Between 2006 and 2010, the number of wooden
houses rose fivefold and increased by 50% within 2015, while the use of other construction materials decreased by 40% between 2006 and 2010 and has increased of
30% within 2015. Italy is the fourth European player in the wooden building sector,
overcoming countries with an ancient timber construction tradition such as Austria,
Finland, France and the Netherlands. The highest concentration of timber construction industries is in Lombardy, followed by Veneto, Emilia Romagna and Trentino
Alto Adige.
The benefits in using preassembled timber components for building constructions are manifold: the manufacturing costs can be significantly decreased by the
seriality and modularity of the production, while the rapidity of assembly ensures a
short duration of the onsite construction, without decreasing the structural stiffness
and the thermo-acoustic performances. Moreover, generally, prefabricated construction technologies allow the optimization of the manufacturing process, as well as
decreasing fossil-carbon emissions during material processing and assembly.
Modular timber constructions, especially if based on massive wooden elements
(e.g. plywood, LVL panels, cross-laminated timber (CLT), etc.), also allow the storage
O. B. Carcassi et al.
and Di Carlo 2010; Lavagna et al. 2018). As a matter of fact, the fossil carbon
emitted by manufacturing of materials and construction might significantly affect
the carbon saving from operational energy (Rovers 2014). The building material
selection strongly affects the overall environmental impact of a building, especially
the selection of the materials for the structural frame and the building envelope (i.e.
basement, exterior walls and roof) on which the former has a major influence (Pal
et al. 2017; Paleari et al. 2016).
The following work presents the results of some studies conducted with the aim of
assessing the benefits, from the point of view of environmental impact, deriving from
the use of bio-based materials as an alternative to conventional building materials
for both new and existing buildings undergoing major renovations.
2 Timber in the Italian Construction Industry
The consumption of forest products has increased in all European regions in the last
20 years, partly supported by public policies which encouraged the use of wood in the
construction and renovation sector through the implementation of energy efficiency
policies (Martín Vallejo 2015).
Reduced times for construction, combined with high-performance expectations,
increased the interest towards prefabricated construction systems. Among these,
wood-based preassembled components are those accounting for the largest growth
in the Italian market, with approximately 2.8% of the housing assets and 8.5% of the
total building stock (Pittau et al. 2016). The picture provided by Centro Studi FederlegnoArredo in their report ‘Rapporto case ed edifici in legno’ suggests a countertrend with respect to the total amount of investments in the construction industry:
starting from 2010, more than 3,000 timber buildings have been built, 89% of which
are residential (Gardino 2015). Between 2006 and 2010, the number of wooden
houses rose fivefold and increased by 50% within 2015, while the use of other construction materials decreased by 40% between 2006 and 2010 and has increased of
30% within 2015. Italy is the fourth European player in the wooden building sector,
overcoming countries with an ancient timber construction tradition such as Austria,
Finland, France and the Netherlands. The highest concentration of timber construction industries is in Lombardy, followed by Veneto, Emilia Romagna and Trentino
Alto Adige.
The benefits in using preassembled timber components for building constructions are manifold: the manufacturing costs can be significantly decreased by the
seriality and modularity of the production, while the rapidity of assembly ensures a
short duration of the onsite construction, without decreasing the structural stiffness
and the thermo-acoustic performances. Moreover, generally, prefabricated construction technologies allow the optimization of the manufacturing process, as well as
decreasing fossil-carbon emissions during material processing and assembly.
Modular timber constructions, especially if based on massive wooden elements
(e.g. plywood, LVL panels, cross-laminated timber (CLT), etc.), also allow the storage