Board materials: what belongs where

Why the board decides

The frame carries the load, but what the user perceives — the hardness of the wall, its dullness, its fire resistance — comes from the board on it. The same stud frame with two different linings gives two walls of different quality.

So choosing the board is a design question, not a procurement one.

Outside: a cement-based board

Fibre-reinforced cement board

Made from Portland cement, aggregates and other inorganic materials, with glass-fibre reinforcement on both faces, worked into the cement matrix. It can be used internally and externally: on walls, ventilated façades, suspended ceilings and as cladding. It can be plastered and painted, and it can be a substrate for ceramic finishes or for an external insulation system.

In practice this is the best choice for the outer, hard layer of a framed wall. Impact-resistant, non-absorbent, and it improves the logic of the build-up too: if we already have a board that provides hardness, let it be the outermost layer — not the insulation. Continuous external insulation.

What we usually recommend: the FIBRAN Cemnext board, distributed in Hungary by Albagips Exim Kft. A good material, and in the outermost plane of the build-up it does exactly what is wanted there.

It has a price, though: a 12.5 mm board at 1200×2000 mm costs HUF 6,409/m² (list price, September 2026). That is roughly twice a better-quality internal plasterboard — in exchange it is external-rated, hard, and needs no separate protective layer behind it.

The same distributor also offers an external, glass-fibre faced gypsum board (Nextboard, 12.5 mm, 1200×2000, HUF 6,001/m², A1 reaction to fire, impregnated). A similar price, but gypsum-based — for a different job.

Cement-bonded particle board

The classic board, known in Hungary as Betonyp and Cetris: roughly 63% wood, 25% cement, 10% water, 2% additives. A hard surface, good impact resistance, resistant to weather, fungi and insects, and hard to ignite.

Cheaper than fibre-reinforced cement board, and in many places good enough. In exchange it is heavy — which shows in the erection and in the self-weight of the structure — and cutting it is dusty, unpleasant work.

Inside: fire and acoustics decide

Denser, multi-layer plasterboard

On the inside, mass is one of the bases of sound insulation. Boards of higher density in several layers build a wall that feels duller and more solid than a thin partition-block wall.

Put up the cheapest plasterboard in a single layer and the same quality cannot be expected — and that will not be the fault of the structure. It is the most common reason somebody finds a light gauge steel wall “hollow”. Sound insulation basics.

Special, reinforced gypsum board

Robust gypsum boards exist that are impact-resistant, water-repellent and high-performing in fire at the same time — up to 120 minutes according to the manufacturer’s data. They make sense where one board has to solve several problems: a public building, an escape route, a heavily used wall.

In price they sit in the better internal category: the Albagips Fibran Super at 12.5 mm, 1200×2000 costs HUF 3,215/m², and the 15 mm, 1200×3000 board HUF 3,776/m² (list prices, September 2026).

Fire-rated board

Where the lining has a fire role, the type of board and its fixing are fixed values. Important: the REI rating applies to the structure, not to the board. Fire-protective boards · What REI means.

What not to put in an external wall

OSB and gypsum-based board. Water-absorbing organic material does not go into an external wall: moisture cannot get lost from a closed light gauge steel wall the way it can from a thick brick wall. Organic and absorbent materials in the wall.

The common counter-example — OSB outside, polystyrene on it, mineral wool between the studs — puts the layers in exactly the wrong order: the hard material inside, the vulnerable one outside.

If the lining braces

Where the design counts on the bracing action of the lining, the type of board, its thickness and the screw pattern are designed values, not a procurement decision. Substituting then changes the structure. Sheathing diaphragm.

Prices and what to do with them

The prices above are list prices as at September 2026. They show two things:

• the order of magnitude — external cement board is around twice an internal plasterboard,
• and where not to save: the outermost layer, the one exposed to impact, is what the owner still perceives after moving in.

For a specific project, ask for a current price: the list price and the purchase price differ, and quantity counts.

The point

The frame is the same everywhere — the board decides the quality of the wall. Outside, a hard, non-absorbent cement-based board; inside, heavy, multi-layer lining. Save on this and you lose exactly the quality the technology was chosen for.