High prices of construction materials and their permanent growth make the Customers pay more attention to optimization of construction costs. We are to discuss ways of saving by building mounting with Mrs. Alla Gulyanova, Chief Engineer of Karkas Company.

What are the ways of saving by building designing?

Our company has been working on the commercial real estate market of Ukraine for 8 years already. Accumulated experience enables us to state that saving is viable and possible. To reduce costs is possible in two ways. The first is to apply cheaper materials which could cause serious operation problems, and the second is application of rational engineering solutions and combination of new technologies.

An example of the building cost reduction could be consideration of individual loading for each of its zones by designing of bearing structures and use of variable cross-section frames made of high-resistance steel. Usually, steel sheets of resistance 245 MPa are used in construction while ASTRON applies steel of resistance 345-355 MPa in its structures. It allows reduction of steel intensity of framework, transportation costs and, in many cases, ground work costs.

Significant saving could be achieved by applying optimal framework for selected structures. Substantial impact on the cost is made by such factors as frame spacing, frame bays, height of the building and rational floor structures. For example, the best saving with our buildings is achieved with frame spacing 7.5 – 9 m.

It is essential to make rational engineering communications and systems of the roofing. Heating and other heavy-weight engineering equipment to be installed on the roof should not be scattered but concentrated in several frame spacings. It allows increasing steel intensity of only few structures. Fixing of engineering mains not on roofing structure but on the columns reduces operation loading on the building framework.

Use of the roof panel of the prefabricated sandwich without inner shaped steel reduces costs of envelop materials significantly. It is especially important for large-scale facilities with large space of envelop materials.

One more cost-reduction solution is use of standardized colours for wall and roof panels which are presented in diverse range for the buildings supplied by Karkas. Non-standard colours are ordered individually and their production is more expensive and time-consuming which extends general terms of the complete building delivery.

What are the cases for applying different types of roofing?

It depends on the construction location, individual building requirements and Customer’s wish.

We recommend our customers to use cheaper panels of prefabricated sandwich without bottom shaped steel for almost all storage and industrial buildings. Such panels are marked as LPR in our buildings, with thickness of thermal insulation being 120 mm and 160 mm. LPR panel uses special element isobloc which prevents from cold joint emerging where thermal insulation is compressed. Such paneling has an esthetic view inside the building since thermal insulation with steam insulation which has even white surface is used.

Examples of such roofing can be observed in supermarkets "Novaya Linia" in Kyiv (Troyeshchina district), Odesa, Lviv, supermarket "Budmaydan" at the Kyiv ring road and other facilities supplied by KARKAS Company.

Since energy-saving has become crucial in Ukraine lately, the necessity emerged to apply thermal insulation of glass wool with thickness of 200 mm for roofing of public and civil buildings. Such width of insulation needs substructures supported by bottom formed steel. In these cases, it is reasonable to use DSR panels (Astron marking) with double shaped steel.

Is it possible to use used bearing structures or panels?

Framework of each building is designed for the operation term declared by the customer and for particular conditions. Consequently, structures designed for some conditions can be inappropriate for other conditions even if the functions of the buildings are identical.

Panels are characterized by the adaptability to certain building and ability to "skin" the framework with view of all its peculiarities. Therefore, applying used panels of prefabricated sandwich for other building makes it difficult to achieve proper insulation effect. In addition, roofing shaped steel is interlaid with insulating tape which glues it strongly and protection coating can be damaged by dissembling. One more reason to avoid applying the used envelop structures is thermal insulation since its tapes are sewed with brackets and can be damaged by dissembling.

How can completeness of the quickly-mounted building influence its cost?

Complete building is more workable and rational characterized as a rule by "polished" mounting procedure which is conducive for time saving. Customer obtains the building from the manufacturer accomplished with project solutions of all nodes, adjoining structures and solid insulation of all joints. Initially, such solution can be more expensive but this technology reduces construction period by several months if compared with other methods. It is related directly to the deadline of putting the facilities into operation and payback period. Besides, declared cost of complete quickly-mounted building does not differ from ultimate cost since it includes all the materials and elements. Initial cost of non-complete building can omit these elements which will inevitably increase the cost of the project throughout construction period.

It is vital for us as the supplier of the quickly-mounted buildings not just to apply high quality materials but to choose proper technical solutions to obtain the best possible result for our Customer in quality, time and price.