What BALCSOFT calculates
BALCSOFT is a program for the design and calculation of balcony anchorage, dealing both with the new slab and with its connection to the structure. It is intended for structural engineers and designers working on balcony additions to existing buildings, on TAMA projects and on new balconies in ordinary construction.
What sets it apart is that combination: it designs the cantilever itself — geometry, reinforcement, cover, fire resistance, creep — and the connection to the existing structure as well, under the same data and in the same file. There is no manual transfer of a result from one tool to another, and no two models making different assumptions about the same balcony.
Balcony type and geometry
The definition opens with the balcony type, followed by the geometry: cantilever L, width B and slab thickness h. These three values govern everything that comes after them — the moment at the root of the cantilever, the demand for top reinforcement and the deflection behaviour over time. The project details are kept alongside them: engineer, contractor, location, level and floor. The level and floor fields matter in additions to existing buildings, where one project takes in different balconies on different floors.
Materials and environment
The materials and environment module defines the concrete grade, the reinforcing steel grade and the aggregate, and the environment type to Table 6.3 — with a maximum water/cement ratio and the cover derived from it. A balcony is an exposed external element, so defining the environment here is not a formality: it is what sets the cover, and indirectly the effective depth of the top reinforcement. The same screen also defines the top bar diameter, the bar spacing and the anchorage of the bar end — that is, not only how much reinforcement is required, but how it is actually anchored.
Loads, fire and creep
The loads screen defines an additional dead load for finishes, the required fire resistance, the category of use to SI 412 part 1.2 (the Israeli standard), the self-weight of the railing and the duration of the sustained load for creep. The last two are what separate balcony design from the design of an ordinary slab: the railing is a permanent load at the free end of the cantilever, and creep under sustained load is the reason balconies age in deflection and not at the moment of loading.
Wind and earthquake — SI 414 and SI 413
The wind load is calculated to SI 414, from a basic wind speed v_b0. The earthquake check is carried out to SI 413. In balcony additions to an existing building these are the two checks that draw most of the checker’s attention, which is why they are separate, explicit modules in the program and not a footnote inside the load calculation.
The existing structure and the connection to it
The existing structure and location module describes what the balcony connects to, and the connection to existing structure module designs the connection itself. This is the part in which a balcony addition differs from a balcony in new construction: the new slab bears on an element that was not designed for it, and the connection is what carries the moment and the shear into the existing structure. BALCSOFT designs both in one continuous sequence.
Railing — SI 1142
The railing is designed to SI 1142, not taken as an agreed point load. It appears twice through the calculation — as self-weight on the loads screen, and as an element checked to SI 1142 — so that the same railing is documented both as mass on the cantilever and as a requirement in its own right.
What the output carries
The output carries the project details entered — engineer, contractor, location, level and floor — alongside the balcony type, the geometry, the materials and environment, the loads, the SI 414 and SI 413 checks, the connection to the existing structure and the railing to SI 1142. It is a single document covering the balcony from the cantilever through to the connection.