Montage steps

1. Preparation for Installation

Before starting the installation, take a close look at the floor plan of the stairs and check the ceiling opening and all specified dimensions against the plan. Pay particular attention to the wall structure, ceiling structure, and the space at the upper stair exit.

Subsequently, check the completeness of the delivered stair parts, unpack all parts, check them, and get an overview of their arrangement in the stairwell. The same applies to fittings and the supplied installation material.

Now lay out the required tools and all aids. Read through the entire assembly instructions carefully so that you fully understand the sequence before starting the installation.

Recommendation for Installation:

The installation should be carried out by at least two people, preferably three or four.

Recommendation for screws: Before inserting a screw into a pre-drilled hole, always apply a small amount of neutral silicone (2 pea-sized beads) into the hole. The silicone facilitates the screwing process and eliminates the risk of screw breakage due to overtightening.

2. Installation of the Outer Stair String

Begin the installation by fastening the outer stair string to the wall. The drill holes are not prefabricated; they must be planned and drilled manually so that they do not collide with installations, niches, or wall openings.

Always try to place one fastening point as close as possible to the stair start — ideally approx. 6 cm below the center of the first tread —, another as close as possible to the exit — usually below the last (or second to last) tread and at a height that avoids hitting the insulation layer in the ceiling. Space the remaining fastening points approx. every two risers between the start and exit — again ideally approx. 6 cm below the center of the respective tread. If suitable and possible, fasten in the locations of existing holes under the treads (primarily made for fastening treads to the stair string) — this reduces the number of cover caps.

If the staircase includes landing(s), place at least two fastening points under the landing.

If the walls in the stairwell are built using a grid construction method (e.g., with studs or reinforcements behind plasterboard or OSB panels), the fastening points must be adjusted and placed exactly in the middle of the reinforcements; do not save on their number. It is recommended to place two screws one above the other.

3. Aligning and Fastening the Outer Stair String

Place the outer stair string against the wall, align it towards the stair exit, support the string, and level it. The upper edge (sawtooth cutout) of the vertical block on the stair string must sit lower (by the thickness of a tread) than the final floor height on the upper floor. Check the flatness of the exit edge with a spirit level and level if necessary. Pay attention to floor unevenness — even with poured floors! If the final floor height has not yet been determined, use suitable shims to set the stair string to the correct height. Lightly secure the stair string — fasten it at all points without tightening too firmly.

4. Aligning the Outer Stair String

Attention: The stair string must not adapt to wall unevenness or become wavy. Use suitable shims.

Important note: The delivered staircase is precisely rectangular in floor plan — therefore, in case of a deviation from a right angle at the exit, the stair string must be shimmed or moved accordingly; otherwise, correct installation of treads, landings, and the inner stair string will not be possible.

5. Assembly of the Stair Exit

Now assemble the stair exit: Apply neutral silicone to the rear edge of the second-to-last tread, where the last riser joins. Align the riser flush and screw it with three 5×45 screws from behind into the tread. Next, apply a thin layer of construction adhesive into the bottom of the groove for the riser in the last (exit) tread. Subsequently, place this tread onto the riser and tap it home. The riser must be inserted all the way to the bottom of the groove. Provisionally fix it, e.g., with adhesive tape.

Prepare the inner stair string — glue dowels for the exit post into two front holes, and glue another two dowels into the horizontal seat for the second-to-last tread. Also glue dowels for the second-to-last and last treads into the outer stair string. Apply silicone to the seat surfaces and the front face of the stair string (next to the dowels). Apply a thin layer of neutral silicone to the contact surface of the outer stair string and the last riser (i.e., onto the vertical block).

Next, take the completed assembly of the second-to-last tread, riser, and exit tread, apply adhesive into the dowel holes, place the entire assembly onto the dowels of the inner stair string, and tap it home completely with a mallet. From the side of the stair string, inside the hole under the second-to-last tread, secure the tread to the stair string with an angled 6×60 screw.

6. Mounting the Exit Post

Now place the exit post against this assembly, slide its mortise onto the exit tread, and tap it onto the dowels on the front face of the stair string. Next, screw it to the stair string using two 6×100 screws. Apply neutral silicone to the mortise and contact surface with the riser beforehand, and apply adhesive into the dowel holes! Secure the exit tread from behind the post with a shorter screw.

7. Installation and Fastening of the Exit

Place the assembly from the previous step against the exit edge and slide the free ends of the treads onto the dowels of the outer stair string. Tap home. From the side of the stair string, inside the hole under the second-to-last tread, secure the tread to the stair string with an angled 6×60 screw. Engage the post overhang (tooth) on the inner side onto the exit edge of the stair opening.

Support and level the assembly. Check the level with a spirit level and correct if necessary.

Now plan and drill preferably 2 fastening points and fasten the exit. Always fasten along the axis of the exit post = through the riser and post together.

Pay close attention to the strength and location of fastening points relative to insulation, electrical cables, water, or heating lines!

At this stage, the outer stair string is fastened to the wall, the two last treads with the riser are secured, and the inner stair string with the post is attached to them on the inner side.

8. Aligning the Inner Stair String

Properly support and level the inner stair string in all planes. For better verification of the distance between the outer and inner stair strings, it is recommended to place one tread dry on the dowels in the middle of the staircase, as well as tread No. 2. Continuously check for levelness. If everything is in order, firmly fasten the start of the inner stair string under the first tread to the floor — using a floor anchor. Holes under the 1st tread are pre-drilled for this anchor. Pay attention to any existing underfloor heating!

Further attention — the anchor shares the lateral hole in the stair string with the future threaded rod for fastening the 1st tread; sufficient space must remain in the hole!

9. Installation of Tread No. 1

Apply neutral silicone evenly over the entire surface of the horizontal seats on both stair strings for tread No. 1. Also apply silicone to the vertical surfaces of the stair strings at the contact points with risers No. 1 and No. 2.

Apply construction adhesive into the dowel holes in both the stair string and tread, and tap dowels into the stair string. Mount riser No. 2 to the first tread:

Apply neutral silicone to the rear edge surface of tread No. 1 — in the form of beads spaced 1.5 cm parallel to both the top and bottom surfaces of the tread.

Align and screw riser No. 2 with three 5×45 screws from behind into tread No. 1. Wipe off any excess neutral silicone. Now insert riser No. 1 into the groove of the first tread from below.

Before doing so, apply construction adhesive into the groove of the tread! Spread it lightly so that the adhesive bead does not fall out during the next step. Now screw threaded rods from below the tread into the insert nuts.

Subsequently, place this assembly of tread and both risers onto the dowels in the stair strings and tap home with a mallet.

From the side of the stair strings, inside the hole under the tread, screw collar nuts onto the threaded rods and tighten them. If the lower floor is not yet laid under the staircase, shim and secure riser No. 1 against sliding out of the groove in the tread.

10. Installation of Treads from the Stair Start

Next, mount the treads step by step moving upwards from the stair start:

Apply neutral silicone evenly over the entire surface of the horizontal seats on both stair strings for tread No. 2. Also apply silicone to the vertical surfaces of the stair strings at the contact points with riser No. 3.

Apply construction adhesive into the dowel holes in both the stair string and tread, and tap dowels into the stair string.

Apply neutral silicone to the rear edge surface of tread No. 2 — in the form of beads spaced 1.5 cm parallel to both the top and bottom surfaces of the tread.

Align and screw the riser with three 5×45 screws from behind into the tread. Wipe off any excess neutral silicone. Now apply construction adhesive to the bottom of the groove for riser No. 2. Again, spread it lightly so that the adhesive bead does not fall out in the next step.

Then place the assembly of tread No. 2 with riser No. 3 onto the dowels in the stair strings and the protruding riser No. 2, and tap home completely with a mallet.

From the side of the stair strings, inside the hole under the tread, secure the tread to the stair strings with an angled 6×60 screw.

Proceed in the same manner up to the exit. Because the second-to-last tread is already mounted, the tread and riser in front of it must be mounted separately — first slide the riser diagonally from below into the second-to-last tread, and only then place the tread onto the dowels.

10.1 From an installation perspective, the landing is handled like a tread; due to its greater width, it is secured with angled screws in multiple locations.

11. Final Inspection and Tightening

Now firmly tighten all fastening points in the stair strings. Check the geometry.

12. Installation of Balustrade Posts

Next, mount the balustrade posts. The exit post is already incorporated at the exit. For any intermediate post, first mount a threaded rod into the insert nut of the tread, place the post over it, insert a collar nut into the lateral hole of the post, and tighten it. Attention: The post must be oriented correctly so that the pre-drilled screw holes match the heights and directions of the connected sub-handrails and handrails. Place the start post with its mortise onto the routed front edge of the first (or second) tread and screw it with two screws into the edge of the stair string (through the riser). Apply neutral silicone into the mortise and onto the contact surface with the riser beforehand!

13. Installation of Sub-handrails

Continue the balustrade installation by installing the sub-handrail, or sub-handrails if an intermediate post is present. Position the sub-handrail along the axes of the posts at the specified height and screw it at both ends through the posts.

14. Installation of Balusters and Handrails

Now apply neutral silicone into all holes for the balustrade balusters (in both sub-handrails and handrails). A proven method is applying a bead along the entire length of the longest side wall of the hole. Then insert the balusters into the sub-handrail(s) according to the layout plan. Subsequently, place the handrail(s) onto the balusters, tap into place, and screw through the posts.

15. Cleaning and Capping

Sweep and clean the staircase, and cover all holes with appropriately sized cover caps. Cover caps are fitted over the hole at the rubber seal location and pressed in by hand.

16. Completion of Installation and Curing Time

This completes the entire installation of the staircase. All glued and silicone-sealed connections require approx. 24 hours at normal room temperature to cure completely. During this time, the staircase should not be subjected to loads.