The project in five facts.
Challenge, approach and results.
In the initial chapter, they examined the structural elements or layers of roofs and the various materials that make up these layers in order to understand roof composition. They also presented the types of roofs that were crucial for the cost comparative analysis. The results of the analysis they conducted showed the following: COST OF CONSTRUCTING AN INVERTED FLAT (NON-ACCESSIBLE) ROOF FOR THE DESIGNED BUILDING:
Problem
In the initial chapter, they examined the structural elements or layers of roofs and the various materials that make up these layers in order to understand roof composition.
Solution and Method
They also presented the types of roofs that were crucial for the cost comparative analysis. The purpose of the diploma thesis was, with the help of professional literature and knowledge acquired during their education at the institute of technology, to carry out a cost comparative analysis between two types of roofs for a residential building ‒ flat roofs and pitched roofs. In the analytical, concluding part of the diploma thesis, they conducted a cost analysis of a representative of each roof type, i.e. for an inverted flat (non-accessible) roof and a pitched roof with a suspended drywall ceiling.
The reason for choosing these two roofs was that these representatives of individual types are the simplest to construct and thus mutually comparable. In the analysis, they considered all necessary comparable characteristics of materials, with thermal insulation playing the most important role. In calculating the latter, the minimum requirements of the Rules on the Efficient Use of Energy in Buildings (Official Gazette of the Republic of Slovenia, n.d.) were taken into account.
Based on the price analyses of individual items of structural elements, they calculated the construction value of each roof type for the same designed building.
Results
The results of the analysis they conducted showed the following: COST OF CONSTRUCTING AN INVERTED FLAT (NON-ACCESSIBLE) ROOF FOR THE DESIGNED BUILDING: The cost of supply and installation of C25/30 concrete with all works and transfers amounts to 3,834.04 euros. The costs of supply, cutting, bending and tying of reinforcement (reinforcing steel – ribbed reinforcement S 500 and mesh S 500 B) amount to 3,855.27 euros. The costs of formwork for reinforced concrete amount to 3,837.20 euros.
The costs of supply and installation of slope concrete amount to 2,003.75 euros. The costs of waterproofing implementation amount to 1,649.65 euros. The costs of supply and laying of thermal insulation amount to 4,581.49 euros.
The costs of supply and backfilling of gravel amount to 318.36 euros. The total value of construction works for the construction of a flat inverted non-accessible roof amounts to 20,079.76 euros. COST OF CONSTRUCTING A PITCHED ROOF WITH SUSPENDED DRYWALL CEILING The costs of timber supply and construction of wooden roof structure with battening and covering with vapour-permeable membrane amount to 11,741.36 euros. The cost of roofing and sheet metal works amounts to 6,772.33 euros.
The cost of drywall works amounts to 7,821.90 euros. The total value of construction works for the construction of a pitched roof amounts to 26,335.59 EUR. The hypothesis "The cost of constructing a flat roof for a residential building is lower than the cost of constructing a pitched roof", which they highlighted at the beginning of the diploma thesis, is thus confirmed.
The comparative analysis showed us that the cost of constructing an inverted flat (non-accessible) roof is 23% lower than the cost of constructing a pitched roof. The research of individual structural elements showed that the methods of achieving waterproofing of a residential building roof are different. In a flat roof, this is achieved through the implementation of a waterproofing layer – coating with Ibitol and welding of bitumen strips.
In a pitched roof, the waterproofing layer is represented by the secondary roofing, which is simultaneously a vapour-permeable membrane. The primary waterproofing layer is represented by the roofing. Achieving waterproofing in flat roofs is thus much more time-consuming, as drainage must be ensured, i.e. slope concrete must be made, and then a bitumen coating must be applied and bitumen strips must be welded.
In a pitched roof, there is no need to worry about the slope, and the secondary roofing is much easier and faster to lay on the roof structure. The third hypothesis, that the construction of a flat roof for a residential building is more time-consuming than the construction of a pitched roof, is also confirmed. In the construction of a flat roof, the formwork of the reinforced concrete slab with support up to a height of 3 metres is very time-consuming. This is followed by laying reinforcement and concreting of reinforced concrete. After the concreting itself, one must wait for adequate concrete strength, which is achieved after twenty-eight days, before formwork removal should begin, etc.
Only then can the next layers be tackled. From all of the above, it is thus possible to recognise that the construction of a pitched roof is more expensive, but the construction is approximately 50% faster compared to a flat roof.
Module, programme and stories.
Your diploma project for a real company.
A diploma thesis at Academia solves a challenge from a company – often the one where you do your 800 hours of placement. Read about the Gradbeništvo module or book a consultation.