Montage steps

1. Preparation for Installation

A thorough preparation is critical before beginning the installation. Carefully study the floor plan of the staircase and verify the ceiling opening against the plan dimensions. Take careful note of the wall structure, the ceiling structure, and the available space at the stair exit to ensure a correct fit without requiring retrofits.

Unpack and inspect every individual piece to check for completeness and to confirm its exact position in the stairwell. Verify and lay out all fittings and auxiliary materials in advance.

Prepare all necessary tools and assembly aids. Review this manual completely beforehand to gain a solid theoretical understanding of the workflow.

Personnel and Screwing Recommendations

• Personnel: We recommend executing the installation with at least two people, preferably three or four, as several parts are large, heavy, and require multiple people to handle safely and efficiently.
• 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. Planning and Drilling Anchor Points

Installation begins by anchoring the 3rd outer string (exit string) to the wall. Because the anchoring holes are not pre-drilled, they must be carefully planned and drilled to avoid colliding with electrical installations, niches, or existing cavities in the wall.

• First Anchor Point: Place it as close as possible to the stair ascent — approx. 6 cm below the centre of the first tread.
• Exit Anchor Point: Place it as close as possible to the exit, below the last or second-to-last tread, and at a height that does not hit or compromise the insulation layer of the ceiling.
• Intermediate Anchors: Place additional anchor points at intervals of approx. every two rises along the string, between the ascent and exit, also approx. 6 cm below the centre of the respective tread. Where possible, position these anchor points inside the existing holes under the steps (intended for securing the steps to the string) to minimize the number of required cover caps.
• Landing Anchors: If the staircase features a landing, set two anchor points under each section (leg) of the landing.

If mounting against framed walls featuring a grid system (with reinforcements and studs behind plasterboard or OSB panels), align the anchor points exactly with the centres of these reinforcements. Do not economize on the number of anchors; where necessary, two anchor points can be placed vertically one above the other to ensure maximum stability.

3. Aligning and Connecting the Outer Strings

Press the 3rd outer string (exit string) against the wall, guide it up to the exit edge, support it, and align it carefully. The upper edge (saddle) of the vertical timber beam on the string must sit lower than the final floor height of the upper floor by exactly the thickness of the tread. Check that the exit edge is perfectly level.

Attention: Uneven floors at the stair exit are a frequent issue, even with screed floors! If the final story height has not yet been established, bring the string to the correct height using suitable shimming plates. Once in position, secure the string by tightening all anchor points lightly; do not tighten them fully yet to allow for future adjustments.

Next, glue the wooden dowels into the prepared openings and screw the threaded rods into the 2nd outer string to link it to the 2nd outer corner. Apply glue to the joint interface, specifically the front face of the 2nd outer string. Slide the string onto the dowels, push it into the corner, press it against the wall, support it, and align it.

Carefully pull the pre-mounted threaded rods in this string out through the side holes using your fingers and screw them into the drive-in nuts of the 3rd outer string (at least 4 full threads). This step requires sensitivity, practice, and precise positioning of the parts relative to each other. It is recommended to test-screw these threaded rods into the drive-in nuts at the start of assembly to get a feel for the process.

Finally, screw the collar nuts onto the ends of the threaded rods inside the side holes and tighten the corner connection to stabilize the structure.

3.1 Assembly of the 1st Outer Corner

Glue the wooden dowels into the 1st outer string (ascent string) and screw the threaded rods into the 2nd outer string to join them at the 1st outer corner. Apply glue to the joint interface, ideally on the front face of the 1st outer string. Slide the outer ascent string onto the threaded rods and dowels, align it with the corner, press it against the wall, support it, and level it precisely.

Screw the collar nuts onto the threaded rods in the side holes and tighten the corner connection firmly. If the floor height is not yet finalized, use suitable shimming plates to ensure the strings sit at the correct elevation. Check the levelness of the saddle for the treads and correct it if necessary to enable a precise installation of the subsequent steps.

Anchor the 1st and 2nd outer strings to the wall at all designated points, ensuring you do not overtighten them yet so that later adjustments remain possible.

Important Realignment Note: Ensure that the strings do not become wavy by following the unevenness of the wall. Use suitable packing/shimming materials where necessary to anchor the strings evenly and stably.

3.2 Exit String Threaded Rods

Screw the threaded rods into the two holes on the side of the vertical timber beam on the 3rd outer string (exit string). These holes are positioned so that a drive-in nut sits at the end of each hole. Screw the threaded rods into these drive-in nuts to ensure a stable connection, which is vital for the strength of the string in the upcoming assembly stages. Once inserted, the connection can be tightened further to securely anchor the 3rd outer string against the wall.

4. Pre-assembling the 3rd Inner String and Anchor Plate

Prepare the 3rd inner string (exit 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.

Position the string at the exit edge, support it, and align it. The distance between the two exit strings is strictly defined by the anchor plate.

Apply silicone to the contact points between the step strings and the anchor plate to ensure a tight seal. Slide the anchor plate onto the threaded rods and push it toward the exit. Place the collar nuts onto the ends of all four threaded rods within the openings and screw them tight, verifying that all parts fit together cleanly and accurately.

 

5. Mounting and Anchoring the Exit Assembly

Plan and drill 2 to 4 holes into the anchor plate for fastening it to the exit, and anchor the plate securely. Pay close attention to the structural integrity of the connection and the exact location of the anchor points to prevent conflicts with insulation or the routing of electrical, water, and heating lines.

Status Check: At this stage, all three outer strings are anchored to the wall, the anchor plate is fixed at the exit, and the 3rd inner exit string is connected to the anchor plate on the inside. This inner string (at the 2nd inner corner) is currently only loosely supported and not yet permanently anchored.

6. Connecting and Aligning the Inner Strings

Glue the wooden dowels into the 1st inner string (ascent string) to connect the strings at the 1st inner corner. Coat the joint interface with glue, preferably on the front face of the ascent string. Once the wooden dowels are inserted, slide the 2nd inner string onto the dowels and secure the connection using two 6×100 screws.

Next, connect both inner strings at the 2nd inner corner to the already mounted 3rd inner string as a single unit. Follow the same procedure as the first inner corner: glue the wooden dowels into the 2nd inner string, coat the joint interface with glue (again on the front face of the 2nd inner string), and slide the strings with the dowels into the holes of the 3rd inner string. Secure this connection with two 6×100 screws as well.

Properly support and align the entire inner string assembly (just as was done for the outer sides). To accurately check the spacing between the outer and inner strings, we recommend provisionally placing a tread before each corner, another directly behind each corner, and tread No. 2 onto the dowels. Verify the levelness during this test.

Once everything is correctly aligned, firmly anchor the ascent of the inner string to the floor under the first step using the floor anchor. The corresponding holes for this anchor are located under the 1st step.

Attention: The presence of underfloor heating must be strictly accounted for at this location!

Note: The floor anchor shares the hole on the side of the string with the future threaded bolt used to secure the first tread. Ensure that enough space remains for the threaded bolt!

7. Installation of Step No. 1

Depending on your staircase design, follow option A (without risers) or option B (with risers):

Option A: For Staircases WITHOUT Risers

1. Apply silicone evenly across the entire surface of the horizontal saddles of both stair strings designated for tread No. 1.
2. Apply construction adhesive into the holes for the wooden dowels in the string as well as in the tread, and insert the wooden dowels into the string.
3. From the underside of the tread, screw the threaded rods into the screw-in nuts of the strings.
4. Place the tread carefully onto the wooden dowels in the strings and tap it with a rubber mallet to seat it firmly into position.
5. Screw the collar nuts onto the threaded rods on the side of the strings underneath the tread and tighten them securely.

Option B: For Staircases WITH Risers

1. Apply silicone evenly across the entire surface of the horizontal saddles of both stair strings designated for tread No. 1. Also apply silicone to the vertical faces of the strings where they interface with risers No. 1 and No. 2.
2. Apply construction adhesive into the holes for the wooden dowels in the string as well as in the tread, and insert the wooden dowels into the string.
3. Mount Riser No. 2: Apply silicone beads to the surface of the rear edge of tread No. 1, running 1.5 cm parallel to the top and bottom of the tread. Fit riser No. 2 and screw it into tread No. 1 from the rear side using three 5×45 screws, wiping away any excess silicone.
4. Mount Riser No. 1: Insert riser No. 1 from below into the groove of the first tread. Ensure you apply construction adhesive into the groove of the tread beforehand!
5. Insert & Secure: Screw the threaded rods into the screw-in nuts from the underside of the tread. Slide the tread along with both risers onto the wooden dowels in the strings and tap them into place with a rubber mallet.
6. Tighten the collar nuts onto the threaded rods on the sides of the strings below the tread. If there is no finished floor underneath the staircase, shim and support riser No. 1 to prevent it from slipping out of the tread groove.

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

Mount the remaining treads progressively from the ascent upwards, selecting the appropriate option below:

Option A: For Staircases WITHOUT Risers

1. Apply silicone evenly across the entire surface of the horizontal saddles of both stair strings for tread No. 2.
2. Apply construction adhesive into the holes for the wooden dowels in the string as well as in the tread, and insert the dowels into the string.
3. Position the tread onto the dowels in the strings and tap it carefully with a rubber mallet to seat it correctly.
4. From the string side, inside the hole below the tread, secure the tread by screwing it firmly to the string with a 6x60 screw.
5. Repeat this process identically for every subsequent step up to and including the second-to-last tread.

Option B: For Staircases WITH Risers

1. Apply silicone evenly across the entire surface of the horizontal saddles of both stair strings for tread No. 2. Also apply silicone to the vertical faces of the strings where they meet riser No. 3.
2. Apply construction adhesive into the holes for the wooden dowels in the string as well as in the tread, and insert the wooden dowels into the string.
3. Apply silicone beads onto the surface of the rear edge of tread No. 2, running approx. 1.5 cm parallel to the top and bottom of the tread.
4. Fit the riser and screw it into the tread from the rear using three 5×45 screws, wiping away any overflow.
5. Apply construction adhesive to the bottom of the groove of riser No. 2.
6. Position tread No. 2 together with riser No. 3 onto the wooden dowels in the strings and into riser No. 2, tapping them tight with a rubber mallet.
7. From the string side, inside the hole below the tread, secure the tread firmly to the string using a 6x60 screw.
8. Repeat this process identically for all further steps up to and including the second-to-last tread.

 

8.1 Landing Installation

The landing is handled exactly like a standard tread during assembly, but due to its larger width, it must be secured with screws at multiple locations to ensure structural stability.

9. Installation of the Exit Tread

Mount the final exit step using the guidelines below:

1. Coat the upper edges (saddles) of the vertical timber beams on both strings, as well as the upper edge of the anchor plate, with a uniform, thin layer of silicone. Also apply silicone to the rear edge of the exit tread to prevent subsequent creaking or squeaking.
2. Apply construction adhesive into the holes for the wooden dowels both in the vertical beams and in the tread, and insert the wooden dowels into the prepared holes.
3. Position the exit tread onto the wooden dowels in the strings and tap it carefully with a rubber mallet until it is fully seated.

9.1 Additional Step for Risers

If the staircase configuration includes risers, you must additionally apply construction adhesive to the bottom of the groove of the exit tread before it is fitted. This adhesive must be distributed inside the groove before the final riser is engaged, ensuring that the riser bonds permanently and securely to the exit tread.

10. Final Tightening and Structural Inspection

Completely tighten all anchor points across the strings and the anchor plate, ensuring that all connections are pulled up securely and uniformly.

Thoroughly check the structural precision of the entire assembly, paying critical attention to the alignment of the strings and the correct seating of the treads (and risers, if applicable). Verify that all components stand at a perfect right angle to one another and that the staircase is structurally stable and correctly aligned.

11. Cleaning and Finishing Work

Once the staircase is fully assembled, clean all surfaces thoroughly to remove dust, debris, or tracking dirt.

Cover all installation openings and holes with the custom-fit cover caps. Position the caps onto the holes with the rubber band side facing inward and press them lightly by hand to ensure they sit firmly, securely, and flush with the wood surface.

12. Curing Time

All glued and silicone-sealed joints require approximately 24 hours at normal room temperature to cure completely. Avoid subjecting the staircase to structural loads or heavy traffic during this curing period.