Matters related to saving fuel, energy, and financial resources in particular, with respect to sustainability, are a much-debated topic. This means that one of the main considerations in the design and construction of new buildings, as well as in the case of existing buildings, is their energy consumption during use. Many newly-constructed buildings are already designed as low-energy or passive buildings. Construction systems based on wood are often assessed for these energy standards, as they have very positive thermal-technical properties. Construction time for wood constructions is very short, with a low - sometimes even negative - ecological footprint. The use of wood and structural elements based on wood save non-renewable resources, which is also highly desirable from the perspective of a sustainability philosophy. In terms of construction physics, we often encounter opinions in construction practice that the accumulation properties of wood constructions are not as positive as those of traditional materials such as brick, steel or concrete. With the above in mind, we formulated a hypothesis about the effect of accumulation elements on the energy consumption of wood constructions. The proposed hypothesis gave us an objective prompting us to analyse already completed constructions in actual use in terms of the presence of accumulation elements located in the constructions, and in terms of their effect on the energy consumption of the examined constructions. In our research of these actual wood constructions, we recorded a statistically significant effect of the presence of accumulation elements on the energy consumption of these examined constructions, both in terms of energy use and costs. This means that there is a clear benefit in using accumulation elements in wood constructions. These improvements in the structural properties of wood constructions can ultimately improve the properties of the resulting structure in many respects, whether in terms of cost saving, the level of comfort for users, or sustain ability in general. Another contribution of our work is in raising awareness of constructions based on wood among all those who are involved in the construction process. (C) 2019 Elsevier B.V. All rights reserved.