Montage steps

1. Preparation for Installation

Before starting the installation, study the floor plan of the staircase carefully and check the ceiling opening as well as the dimensions against this plan. Pay close attention to the wall and ceiling structure, as well as the available space at the stair exit.

We also check the completeness of all staircase parts, unpack them, inspect them, and familiarize ourselves with their arrangement in the stairwell. The same applies to the fittings and auxiliary materials required for installation.

Prepare the assembly tools and all necessary aids. Read the entire text carefully beforehand to gain a theoretical understanding of the complete sequence.

Recommendations and Screwing Note

• Personnel: We recommend carrying out the installation with at least two people, preferably three or four.
• Screwing Note: Before driving in any screw, apply a small amount of silicone (approx. two pea-sized drops) into the pre-drilled hole. This facilitates driving it in and reduces the risk of the screw breaking under tensile load.

2. Anchoring the Outer Stair String

The installation begins by anchoring the outer stair string to the wall. The anchoring holes are not pre-drilled; therefore, they must be carefully planned and drilled to avoid collisions with electrical installations, niches, or other holes in the wall.

Ideally, place one anchor point as close as possible to the stair ascent, approx. 6 cm below the centre of the first tread. The next anchor point should be as close as possible to the exit, below the last or second-to-last tread, and positioned so that it does not hit the insulation layer in the ceiling. Place the remaining anchoring points approx. every two rises between the ascent and exit, again approx. 6 cm below the centre of the respective tread.

Where possible, anchor at positions where holes already exist under the steps to minimize the number of required cover caps. If the staircase features a landing, place at least two anchoring points under this landing.

If the walls use a grid construction method — featuring reinforcements and studs behind the plasterboard or OSB panels — adjust the anchor points and place them exactly onto the centres of these reinforcements. Do not skimp on the number of anchor points; it is entirely practical to place several one above the other.

3. Aligning and Securing the Outer Stair String

Press the outer stair string against the wall, push it up to the exit edge, support it, and align it. The upper edge (saddle) of the vertical timber beam on the string must sit lower than the final floor height of the upper floor to account for the thickness of the tread. Check that the exit edge is perfectly level.

Attention: A common problem is the lack of flatness of floors at the stair exit, even with screed floors! If the final story heights have not been determined, bring the string to the correct height using suitable shimming plates.

Once the string is correctly positioned, secure it by anchoring it at all points, but take care not to tighten the anchors too firmly yet. Subsequently, screw the threaded rods into the two holes on the side of the vertical timber beam on the string. There is a drive-in nut located at the end of each hole to ensure stability.

4. Preparing and Installing the Inner Stair String

Prepare the inner stair string by screwing the threaded rods into the two holes on the side of the vertical timber beam on the string. If the string remains visible, a screw-in nut is located inside the hole; otherwise, a drive-in nut is used.

The inner string is now, similar to the outer string before, placed against the exit edge, supported, and aligned. The distance between the two strings is defined by the anchor plate.

Apply silicone to the string at the contact point with the anchor plate. Subsequently, slide the anchor plate onto the threaded rods and press it towards the exit. Place the collar nuts onto the ends of all four threaded rods in the openings and tighten them, ensuring everything fits together well. Check that the saddles for the treads on both strings are level and correct them if necessary.

Important Geometric Note: The delivered staircase is manufactured to be exactly rectangular in its floor plan. In case of deviations from a right angle at the exit, it is necessary to shim the strings and the anchor plate accordingly so that they maintain an exact right angle to each other after anchoring. Otherwise, a correct installation of the steps or the landing is not possible.

5. Fastening the Anchor Plate and Inner String Base

Plan and drill two to four holes in the anchor plate for fastening it to the exit, and anchor the plate. Pay close attention to the stability and the position of the anchor points with regard to insulation as well as the distribution lines for electricity, water, and heating.

To better control the relative distance between the two strings, we recommend provisionally placing and mounting one tread in the first third of the stairs, another in the second third, and additionally tread No. 2 onto the dowels. Verify that they are level.

Once everything is correct, firmly anchor the base (ascent) of the inner stair string to the floor under the first step using the floor anchor. The holes for this anchor are located under the first step.

Attention: Take note of the possible presence of underfloor heating!

Note: The anchor shares the hole on the string side with the future threaded bolt for securing the first tread; therefore, ensure sufficient space is left.

6. Installation of Tread No. 1

Option A: For Staircases Without Risers

Apply silicone evenly across the entire surface of the horizontal saddles of both stair strings for tread 1. Subsequently, apply the construction adhesive into the holes for the dowels both in the string and in the tread, and insert the dowels into the string.

From the underside of the tread, screw the threaded rods into the screw-in nuts. Then, place the tread onto the dowels in the strings and tap it carefully with a rubber mallet. On the side of the strings below the tread, screw the collar nuts onto the threaded bolts and tighten them firmly.

Option B: For Staircases With Risers

If your staircase configuration includes risers, adjust the procedure as follows:

1. Apply silicone evenly across the entire surface of the horizontal saddles of both stair strings for tread 1. Also apply silicone to the vertical surfaces of the stair strings at the contact points with risers 1 and 2.
2. Apply construction adhesive into the holes for the dowels both in the string and in the tread, and insert the dowels into the string. Mount riser No. 2 onto the first tread.
3. For riser No. 2, apply silicone lines to the surface of the rear edge of tread No. 1, running parallel to the top and bottom of the tread at a distance of 1.5 cm. Fit riser No. 2 and screw it tightly into tread No. 1 from the rear using three 5×45 screws. Carefully wipe away any excess silicone.
4. Insert riser No. 1 from below into the groove of tread No. 1. Do not forget to apply construction adhesive into the groove of the tread as well!
5. Screw the threaded rods from the underside of the tread into the screw-in nuts.
6. Fit the tread together with both risers onto the wooden dowels in the strings and tap carefully with a rubber mallet to fix them securely.
7. On the side of the strings below the tread, screw the collar nuts onto the threaded rods and tighten them. If there is no subfloor underneath the staircase, align riser No. 1 and secure it against sliding out of the groove in the tread.

7. Step-by-Step Installation of the Remaining Treads

Standard Procedure (Without Risers)

Mount the treads progressively from the ascent upwards:

1. Apply silicone evenly across the entire surface of the horizontal saddles of both stair strings for tread 2.
2. Add construction adhesive into the holes for the dowels both in the string and in the tread, and insert the dowels into the string.
3. Place the tread onto the dowels in the stair strings and tap it carefully with a rubber mallet.
4. To secure the tread, screw it from the string side in the hole below the tread to the string using a 6x60 screw.

Repeat this process for all subsequent treads up to and including the second-to-last step.

Adjusted Procedure (With Risers)

For configurations featuring risers, adjust the step-by-step process as follows:

1. Apply silicone evenly across the entire surface of the horizontal saddles of both stair strings for tread 2, and apply silicone to the vertical surfaces of the stair strings at the contact point with riser No. 3.
2. Add construction adhesive into the holes for the dowels both in the string and in the tread, and insert the dowels into the string.
3. Apply silicone lines to the surface of the rear edge of tread No. 2, running parallel to the top and bottom of the tread at a distance of 1.5 cm. Fix the riser into the tread from the rear using three 5×45 screws and wipe away any overflowing silicone.
4. Apply construction adhesive to the bottom of the groove for riser No. 2.
5. Place the entire unit (tread No. 2 with riser No. 3) onto the dowels in the strings and riser No. 2, and tap it carefully with a rubber mallet.
6. Secure the tread from the string side in the hole below the tread using a 6x60 screw.

Repeat this process for all subsequent treads up to and including the second-to-last step.

7.1 Landing Installation

The landing is installed during assembly in the same manner as the regular treads. However, due to its larger width, it must be secured at multiple points with screws to ensure a stable connection between the landing and the strings.

8. Installation of the Exit Tread

1. Prepare the upper edges (saddles) of the vertical beams on both stair strings as well as the upper edge of the anchor plate. Coat these areas with an even, thin layer of silicone to ensure optimal adhesion and damping.
2. Additionally, apply silicone to the rear edge of the exit tread to prevent creaking and ensure quiet use.
3. Add construction adhesive into the holes for the dowels located in both the vertical beams and the tread, then insert the dowels into the beams.
4. Place the exit tread onto the dowels in the strings and tap carefully with a rubber mallet until the tread is firmly and flushly connected to the strings.

9. Final Geometry and Tightening of Anchors

After all treads have been successfully mounted, completely tighten the anchor points in the strings. Proceed carefully to ensure all connections are stable and secure. Using a suitable tool, tighten the screws at the anchor points that were previously only provisionally secured to permanently fix the strings.

After tightening the anchor points, verify the geometry of the entire staircase. Pay special attention to the alignment of the strings and treads. Use a spirit level to check the levelness of the treads as well as the vertical alignment of the risers (if applicable).

If necessary, make minor corrections by slightly readjusting the strings or steps, ensuring the staircase remains stable and free of unwanted structural tension. Once all checks are complete and the geometry is correct, the structural assembly is successfully finalized.

10. Cleaning and Finishing Work

Clean the staircase thoroughly and cover all open holes with the matching caps. Place the cover caps onto the holes with the rubber band side first, and then press them in by hand until they sit tightly in place.

11. Curing Time

All glued and silicone-sealed connections require approximately 24 hours at normal room temperature to cure completely. Do not subject the staircase to loads during this period.