On June 15, 2019, amendments to the main regulatory document on the design of thermal protection systems came into force. We are talking about SP 50.13330.2012 Thermal protection of buildings. Amendment No. 1 to the document was approved by order of the Ministry of Construction of the Russian Federation of December 14, 2018 No. 807 / pr.
This standard regulates the design of thermal protection of residential, public, industrial, agricultural and warehouse buildings under construction or reconstructed with a total area of more than 50 m², in which it is necessary to maintain a certain temperature and humidity regime.
Prior to the publication of this change, the designers faced certain difficulties when performing thermal engineering calculations of the enclosing structures in contact with the ground. For these structures, the baseline value of the required heat transfer resistance was not standardized. Therefore, most often, experts in their calculations took a standardized indicator for external walls located above the ground level.
With Amendment No. 1 in the standard, note 3 to Table 3 appeared under the title "Basic values of the required resistance to heat transfer of enclosing structures" in section 5 "Thermal protection of buildings". The wording of the note is as follows: "The normalized value of the reduced resistance to heat transfer of the part of the wall located below the ground level to a depth of at least 1 m should be taken the same as for the wall located above the ground level." In other words, from June 15, 2019, the base value of the required resistance to heat transfer of a part of the wall within the depth below ground level by at least 1 m should be taken the same as for the outer walls above ground level.
With the publication of Amendment No. 1 to SP 50.13330.2012, there is an unambiguous basis for determining the normalized value of the reduced heat transfer resistance of enclosing structures in contact with the ground.
With the improvement of regulatory documents, designers have more opportunities to substantiate the adopted design decisions with the use of effective high-quality PENOPLEX thermal insulation® from extruded polystyrene foam. Today, these products are used on almost any construction site due to their high heat-shielding properties, stability of thermal performance, high strength, durability and environmental friendliness. It should be especially emphasized the expediency of using PENOPLEX boards® for thermal protection of underground structures, which are in conditions of high humidity, and extruded polystyrene foam has almost zero water absorption.
The manufacturer of these products, PENOPLEKS SPb LLC, renders great assistance to designers, first of all, in the development of the regulatory framework. The company, together with the country's leading design institutes, has developed a number of methodological documents and organization standards. In particular, when designing the lower part of buildings and structures, specialists will be interested and useful documents such as STO 54349294-001-2015 “Organization standard for the use of PENOPLEX® in the enclosing structures of the first and basement floors "and STO 36554501-012-2008" The use of thermal insulation from polystyrene foam extrusion boards PENOPLEX® in the design and construction of shallow foundations on heaving soils ".
Updating the regulatory framework in terms of calculating buried structures is especially important today in the context of the trend for the development of underground space. In large cities, free land is becoming less and less, and the growth vectors of megalopolises are now mainly directed upwards (skyscrapers) and downwards (underground construction). In a number of countries, urban infrastructure facilities are successfully located underground in large cities: trade, service enterprises, bank branches, etc. It is gratifying that efforts are being made in Russia to develop reliable technical solutions in the field of underground construction on the part of the state and business.
