Staircase installation in Batumi for duplex apartments: steel frame and timber

Which staircase suits a duplex apartment

The shape of the staircase is set by the opening in the slab and by how much floor space downstairs you are prepared to give it. A straight flight is more comfortable and simpler to make, but it is long. A turn saves length, and a spiral staircase takes up the least space and is the least suited to everyday life.

If children or elderly parents live in the apartment, we recommend a straight flight or a turn with a landing: on the narrow end of a winder step it is easy to miss your footing on the way down. How a staircase changes the rest of a duplex apartment renovation is covered on a separate page.

The slab opening: existing or to a design

If the developer has left an opening, we measure it and the headroom: from a step to the slab above it we allow no less than 2 m. An existing opening is often made for a different staircase, and we fit the flight to it.

A new opening, or enlarging an old one, alters the load-bearing slab. That is reconstruction: it needs a permit and a structural engineer's design with calculations, temporary props and a steel frame around the edge, as explained on the page about apartment layout changes. We confirm the procedure for your building with the architect and our partner lawyer before work starts.

Stringers, treads and their dimensions

We weld the frame from steel box section: two stringers along the sides of the flight, or a single one in the centre, a mono stringer. Two stringers are stiffer; a mono stringer looks lighter but needs a larger section. We size the section by calculation for the length of the flight.

We calculate the step height from the finished floor below to the finished floor above, so we measure only after the screeds on both levels are done. We divide the height into equal steps, which usually comes to 16–18 cm with a going of 27–30 cm. A step one centimetre higher than the rest will catch your foot for years.

We cut the treads from edge-glued oak or ash panel about 40 mm thick: it behaves more steadily than a solid board. Pine and larch are cheaper but softer, and are more often painted. We match the tone to the floor and to any other wood cladding in the interior.

How we fix the staircase to the slab and walls

The staircase carries people's weight to the slab below and to the edge of the opening above. There the frame sits on steel plates fixed with chemical anchors. Before drilling we locate the reinforcement with a detector: a bar cut through at the edge of the opening weakens the slab.

Partitions in Batumi new builds are usually aerated concrete block and won't hold a flight, so we fix only the handrail to them, with through bolts. We set the plates on resilient pads and tighten the anchor nuts over resilient washers. Without this isolation every step goes into the slab under the lower level, that is, into the neighbours' ceiling. How this kind of noise is reduced is covered in the section on apartment soundproofing.

Balustrades for the staircase and the double-height space

We fit the balustrade along the flight and along the edge of the opening upstairs, using metal posts, glass or timber balusters. The glass is laminated, bonded from toughened sheets: on impact the fragments stay on the interlayer.

We set the handrail about 90 cm above the nosing of the steps, and make the balustrade around the opening upstairs at least a metre high. In an apartment with children we keep the gap between posts to no more than 10 cm and fit no horizontal rails, so that nobody can climb them. We fix the posts and glass to the concrete, not to the cladding: cladding won't take a sharp pull on the handrail.

Order of work and step lighting

The frame and treads are made in the workshop while the finishing goes on in the apartment. We install the frame before the last coat of paint goes on the walls, fit the treads and balustrade at the end, and until the apartment is handed over the flight stays covered with cardboard.

We decide on the lighting before plastering: wall lights by the steps and LED strip under the treads need a cable, and on a finished wall it can't be run without chasing. Switches at the bottom and top, and night-time switching by a sensor, are planned together with the apartment lighting layout.

How much staircase installation in Batumi costs for a duplex apartment

A turnkey steel frame staircase with timber treads and a balustrade, 12–16 steps, costs from 12,900 to 19,200 ₾. The price includes labour and materials: the frame with fabrication, painting and installation, the treads, the balustrade and the handrail. The frame on its own costs 5,700–8,400 ₾, and an oak or ash stair tread, finished and installed, from 350 to 480 ₾ each.

You can save on the wood species: a solid pine or larch stair tread blank costs 70–115 ₾, but that is the material only, with no finishing or installation. We price the balustrade by length, from 690 to 1,080 ₾ per linear metre installed, and a long edge along the double-height space pushes up the total. Winder steps, a mono stringer and lighting for every step cost more. The final cost is set after the site measurement and once the estimate is agreed.

What to check when you sign off a staircase

• the steps are all the same height: we allow a difference of no more than 5 mm;
• the treads don't creak or rock when you stand on the edge;
• the frame doesn't hum or flex when you come down quickly;
• the balustrade doesn't give when you lean your full weight on it;
• the welds are ground smooth and painted, with no chips after installation.

You can also sign off the staircase by video call: the foreman will show you every joint in close-up.