Skip to content
Knowledge hub

Engineering knowledge.
Sheet. Steel. Halls.

Technical guides from our own production in Đakovo: trapezoidal sheets and roof coverings, sandwich panels, gutters and flashings, steel structures to EN 1090 and prefabricated halls. Standards, load tables and practice from the site — for Slavonia, all of Croatia and the EU.

EN 1090-2 and EXC classes: what the certificate of your steel hall really guarantees
Steel structures and halls

EN 1090-2 and EXC classes: what the certificate of your steel hall really guarantees

“Executed to EN 1090-2” is a sentence with no content until the class is stated. An interactive class selector (CC × SC × PC), the differences between EXC2 and EXC3 in figures and nine documents you may ask for before signing.

8 September 2026
11 min
Hall 10 × 30: the anatomy of the most requested size — sections, mass, price, permits
Steel structures and halls

Hall 10 × 30: the anatomy of the most requested size — sections, mass, price, permits

We have dissected our own standard hall of 300 square metres: why an IPE 330 column with an IPE 240 rafter, where exactly 7,438 kg comes from, what a single structural calculation covers without being repeated — and two legal facts for this very size: the checking engineer at the threshold of a 10 m span and the conceptual design for agricultural use.

8 September 2026
8 min
Prefabricated hall price 2026: the real cost breakdown by item
Steel structures and halls

Prefabricated hall price 2026: the real cost breakdown by item

We are publishing the structure of the quotation calculation for our standard 10 × 30 × 5 m structure — mass, sections and starting “from” prices (structure from 22,500 € excluding VAT). Along with that: what share of a turnkey investment the structure is, which costs the law has abolished or moved, and why the lightest structure is not the cheapest.

8 September 2026
11 min
Which prefabricated hall do you need — and what the quotation must state
Steel structures and halls

Which prefabricated hall do you need — and what the quotation must state

The same square metre of hall can cost seventy or five hundred euros, depending on what is in it. An interactive selector by use with typical spans and heights, nine items without which two quotations are not comparable at all, and six facts with which you can get a serious budget quotation straight away.

8 September 2026
10 min
Prefabricated or masonry hall: what really differs — and what is a myth
Steel structures and halls

Prefabricated or masonry hall: what really differs — and what is a myth

Three myths put to the test (temporary status, tax depreciation, “steel rusts”) and a comparison of six properties for which a source exists: permits, time, spans, thermal inertia, alterations and fire. There is no price for masonry construction here — because we would have to invent it.

8 September 2026
9 min
A guide to prefabricated steel halls 2026: timescales, permits and price
Steel structures and halls

A guide to prefabricated steel halls 2026: timescales, permits and price

Nine phases from the enquiry to the occupancy permit, with realistic timescales and a clear separation between what the regulations actually prescribe and what is an estimate. An interactive permit triage under the new Building Act (NN 155/25) and an explanation of why two completely different prices per square metre circulate on the market.

8 September 2026
14 min
Agricultural hall up to 600 m²: from the plot to the occupancy permit with a conceptual design
Steel structures and halls

Agricultural hall up to 600 m²: from the plot to the occupancy permit with a conceptual design

The 600 square metre limit is the most important figure in the new Building Act for agriculture. Seven steps of the easier route — with article numbers — plus three traps: gross floor area is not the footprint, the use is determined by the spatial plan, and a span of 10 m leads to the checking engineer even for a “small” hall.

8 September 2026
9 min
Weld inspection and NDT: what “all welds inspected” really means
Steel structures and halls

Weld inspection and NDT: what “all welds inspected” really means

At handover you are given a piece of paper: “all welds inspected, no objections”. Who looked, with what, at how many welds and against which criterion? Four test methods and what each of them sees, why a weld must not be tested too early, when 10 % turns into extended testing, and six things without which a report proves nothing.

8 September 2026
10 min
Bolted connections in a steel hall: why the same M20 holds 27 or 69 kN
Steel structures and halls

Bolted connections in a steel hall: why the same M20 holds 27 or 69 kN

The bolt is the cheapest part of a hall and the only one that somebody tightens by hand on site. Connection categories A to E to EN 1993-1-8, the preload force to EN 1090-2, the four friction classes from Table 18 and the most expensive error during erection — the painted faying surface. With a calculator of the slip resistance per bolt.

8 September 2026
11 min
Corrosion protection of a steel hall: how many microns, and who actually measures them
Steel structures and halls

Corrosion protection of a steel hall: how many microns, and who actually measures them

“It is galvanised” is not a specification — it is a description of a process without a single figure that can be checked later. Corrosivity categories to ISO 12944-2, why the durability class is not a guarantee period, the 80 % rule from ISO 19840 and the clause that makes a contract “to EN 1090-2” deliver untreated edges. With a specification generator you can paste into your enquiry.

8 September 2026
12 min
The column of a steel hall: how it is sized, how it is anchored and where mistakes are made
Steel structures and halls

The column of a steel hall: how it is sized, how it is anchored and where mistakes are made

The same IPE 400 carries 480 kN or 2,540 kN — depending only on whether something holds it laterally. An interactive buckling calculator to EN 1993-1-1, why the thickness of the base plate follows from the concrete class beneath it, anchor tolerances to Table B.23 and seven mistakes that stop the crane on site.

8 September 2026
13 min
Lattice or solid-web girder: which girder goes on your hall and why
Steel structures and halls

Lattice or solid-web girder: which girder goes on your hall and why

Two quotations for the same hall, at similar prices, but with completely different structures. A lattice girder uses less steel but more hours and more square metres of coating, and it is a whole metre deeper — which is paid for on every metre of wall. An eaves-height calculator, where the economics tip over, and seven questions that separate the two quotations.

8 September 2026
10 min
Erection tolerances: why parts “within tolerance” still do not fit together
Steel structures and halls

Erection tolerances: why parts “within tolerance” still do not fit together

The door does not fit the opening. The steel contractor says everything is within tolerance, the builder says the foundation is as designed, the door manufacturer says the opening is out of true — and all three of them can be right. Essential and functional tolerances to EN 1090-2, the collision with EN 13670 at the foundations, and a calculator that shows how much deviation adds up by the time you reach the building envelope.

8 September 2026
9 min
The design for a hall: who may produce it and why there is no binding price without it
Steel structures and halls

The design for a hall: who may produce it and why there is no binding price without it

“I need a hall 20 × 40, how much does it cost?” — a binding quotation cannot arise from those figures, and that is not a sales tactic but a consequence of what the regulations require to go into the structural calculation. An interactive triage of the documentation, who may design and how to check it in the public register, why the checking engineer may not come from the same office, and what the penalties really are.

8 September 2026
13 min
What is not in the hall quotation: utility contribution, water contribution and the connection
Steel structures and halls

What is not in the hall quotation: utility contribution, water contribution and the connection

Investors sign the contractor’s quotation, work out that it fits, and then receive decisions nobody mentioned. A calculator of public charges with the formulas from the rules: why the utility contribution is paid per cubic metre and measured to the top of the roof, why the water contribution was abolished (and old quotations still charge it), and how much a power connection really costs.

8 September 2026
12 min
Modeco from Đakovo: the manufacturer that published its price list
Sheet-metal practice

Modeco from Đakovo: the manufacturer that published its price list

In a trade where almost everything is done “on request”, a company from Đakovo keeps public prices by developed-width class. The story of roof sheet production, CNC bending of flashings and the woman leading a steel company — with figures a journalist can check in the register.

8 September 2026
8 min
Sandwich panels: PUR or PIR core — how to choose the right insulation for your building
Sandwich panels and insulation

Sandwich panels: PUR or PIR core — how to choose the right insulation for your building

The chemistry of fire and of thermal insulation. Why PIR foam is an absolute safety requirement for modern public halls and warehouses.

8 September 2026
7 min
Sandwich panel thickness by use: U-values, the regulation and what really saves on heating
Sandwich panels and insulation

Sandwich panel thickness by use: U-values, the regulation and what really saves on heating

40, 60, 80, 100 or 120 mm? An interactive thickness selector with U-values to EN 14509, the limits of the Croatian regulation (roof 0.25 / wall 0.30), the diminishing saving and the dew point in damp plants.

8 September 2026
9 min
Condensation in a hall: the vapour barrier, panel joints and why the goods go mouldy
Sandwich panels and insulation

Condensation in a hall: the vapour barrier, panel joints and why the goods go mouldy

A hall itself produces tens of litres of water vapour a day — workers, livestock, fresh concrete. An interactive moisture balance, the sealing details of the panel joints, cold bridges and why a sealed hall without ventilation becomes a closed vessel.

8 September 2026
10 min
Roof sweat: the physics of condensation and why fleece is not a luxury but a standard
Sandwich panels and insulation

Roof sweat: the physics of condensation and why fleece is not a luxury but a standard

An analytical look at the dew point under a metal roof. Find out why condensation forms and how anti-condensation fleece physically solves the problem of dripping in prefabricated halls.

8 September 2026
6 min
T-18 vs T-35 vs T-45: how to choose the trapezoidal profile by purlin spacing
Roof coverings

T-18 vs T-35 vs T-45: how to choose the trapezoidal profile by purlin spacing

An interactive engineering guide through three rib heights: the geometry and the weights of the profiles, purlin spacings from the load tables (EN 1993-1-3), snow for continental Croatia and minimum pitches — with a slider that shows which profile stays in the green.

8 September 2026
9 min
Trapezoidal profile vs tile-profile sheet: an engineering guide to optimising the roof structure
Roof coverings

Trapezoidal profile vs tile-profile sheet: an engineering guide to optimising the roof structure

Which profile can take a greater snow load? An in-depth analysis of bending moments, batten spacings and the optimum thickness (0.50 mm vs 0.60 mm) of the sheet.

8 September 2026
5 min
Tile-profile sheet: 5 kg/m² instead of 45 — what a lighter roof means for the roof structure and the price
Roof coverings

Tile-profile sheet: 5 kg/m² instead of 45 — what a lighter roof means for the roof structure and the price

Concrete tiles park 4 tonnes on top of a house of 100 m²; sheet half a tonne. An interactive tonnage calculator, seismics, renovation of asbestos cement, wind and snow guards — honestly, including what is not saved on.

8 September 2026
9 min
The anatomy of steel: why the Z275 coating is the line between a roof for 10 and a roof for 50 years
Roof coverings

The anatomy of steel: why the Z275 coating is the line between a roof for 10 and a roof for 50 years

Not every galvanised sheet is the same. Dive into the microscopic structure of galvanising, passivation and polyurethane top coats. The deconstruction of the Z275 standard.

8 September 2026
8 min
Polyester 25 µm or matt 30–35 µm: which top coat really lasts?
Roof coverings

Polyester 25 µm or matt 30–35 µm: which top coat really lasts?

Primer, top coat, Ruv and RC classes to EN 10169: the interactive anatomy of coating systems from standard polyester to HDX. Why dark RAL shades demand a matt coating and which four questions to ask before ordering.

8 September 2026
8 min
Sizing the gutter and the downpipe: how much water really falls from your roof
Roof drainage

Sizing the gutter and the downpipe: how much water really falls from your roof

Q = r × A × C in practice: an interactive calculator that says whether developed width 250, 330 or 417 is enough for your roof. Why a hopper head in the middle doubles the capacity, what gutter fall, what bracket spacing, and why copper above galvanised sheet destroys the system.

8 September 2026
10 min
Flashings from A to Z: eaves, verge, valley and ridge
Sheet-metal practice

Flashings from A to Z: eaves, verge, valley and ridge

Sheet-metal jargon translated into plain language, a developed-width calculator that shows the price and the sheet yield at once, the bending radius that depends on the coating (not on the steel) and six mistakes you pay for over years.

8 September 2026
10 min
What a metal roof really costs: the calculation on our public price list
Roof coverings

What a metal roof really costs: the calculation on our public price list

The price of a roof is the best-kept secret in the trade — “it depends on the project, get in touch for a quotation”. It does depend, but it can be calculated. A calculator that builds a materials list from the dimensions and the pitch of the house and multiplies it by the prices from our public price list, plus seven items a cheap quotation regularly omits.

8 September 2026
9 min