The ULAMEX Adjustable Hook Handle for Plain Tiles is a height-adjustable stainless steel roof hook engineered specifically for mounting photovoltaic panels on plain tile (Biberschwanz / beaver-tail) roofs. Manufactured from H17 stainless steel (1.4016 / AISI 430), this ferritic stainless hook measures 30 mm wide, 380 mm long and 4 mm thick, with a continuously adjustable height mechanism that compensates for rafter depth variations across the roof surface. The adjustable design eliminates the need for shims, spacers or custom fabrication — the installer simply sets the hook to the required height before tightening the Torx wood screw into the rafter.
Technical Specifications
| Parameter | Value |
|---|---|
| Material | H17 stainless steel (1.4016 / AISI 430), ferritic |
| Height | Adjustable (stepless) |
| Width | 30 mm |
| Length | 380 mm |
| Thickness | 4 mm |
| Fastening | Torx wood screw (into rafter) |
| Finish | Natural stainless (mill finish) |
| Roof type | Plain tile (Biberschwanz / beaver-tail) |
| Service life | 25+ years |
Installation Guide
Begin by lifting the plain tile at the planned hook position to expose the rafter beneath. Position the adjustable hook handle on the rafter so that the hook head emerges between two tile courses without lifting or cracking adjacent tiles. Set the desired height using the adjustment mechanism, ensuring the hook head will sit at the correct level for the PV mounting rail. Pre-drill a pilot hole into the rafter if required by the timber species, then drive the Torx wood screw through the hook base plate into the rafter. Replace the plain tile over the hook body. The tile should rest flat without rocking — if necessary, lightly grind the underside of the tile at the contact point. Repeat at each hook position, maintaining consistent rail height across the array. Space hooks at a maximum of 1,200 mm intervals along each rail line, or as specified by the structural load calculation.
Roof Compatibility
This adjustable hook is designed exclusively for plain tile (Biberschwanz) roofs — one of the oldest and most widespread tile types in Central Europe. Biberschwanz tiles are flat, tongue-shaped tiles laid in a double-cover or crown-cover pattern. The 380 mm hook length provides sufficient reach beneath the tile overlap to anchor securely on the rafter. The height-adjustable design makes this hook particularly suited for renovation projects on older buildings where rafter depths vary from modern standards. Compatible with most plain tile brands and formats including standard 18×38 cm, 15.5×38 cm and regional variations. Maximum recommended rafter spacing: 80 cm (with structural verification for wider spans).
Material Properties — H17 Stainless Steel
H17 (1.4016 / AISI 430) is a ferritic chromium stainless steel containing approximately 16–18% chromium. It offers good corrosion resistance in atmospheric conditions, with a tensile strength of approximately 450 MPa. Unlike austenitic grades (such as V2A / 1.4301), H17 is magnetic and has a lower nickel content, making it significantly more cost-effective while providing fully adequate corrosion protection for roof hook applications where the hook is concealed beneath the tile and not permanently exposed to standing water. The ferritic structure also provides excellent resistance to stress corrosion cracking. H17 is the industry-standard material for PV roof hooks across Central Europe.
Why Choose ULAMEX
ULAMEX has supplied structural steel and stainless steel components for over 35 years, holding EN 1090 certification for the execution of steel and aluminum structures. As a B2B wholesaler, we deliver roof hooks, PV profiles, clamps, fasteners and ballast systems from a single source — reducing procurement complexity and ensuring component compatibility. European delivery with competitive wholesale conditions for solar installers, distributors and EPC contractors.
Frequently Asked Questions
What is the advantage of an adjustable hook over a fixed-height hook for plain tiles?
Fixed-height hooks work well when all rafters are at a consistent depth. On older buildings and renovation projects, however, rafter depths often vary by 10–20 mm or more. The adjustable hook lets you set each hook to the exact height needed, ensuring a perfectly level mounting rail across the entire PV array without shimming or fabrication on site.
Do I need to cut or grind the Biberschwanz tiles when installing this hook?
In most cases, the hook slides beneath the tile course without any tile modification. If the tile does not sit flat on the hook body, a light grind on the underside of the tile at the contact point is sufficient. The slim 4 mm thickness and 30 mm width minimise interference with the tile profile.
How many adjustable plain tile hooks do I need per solar module?
As a guideline, 4 hooks per module are recommended for standard wind zones (up to zone 3). For exposed or high-wind locations, increase to 6 hooks per module. The exact quantity depends on the module dimensions, weight and the site-specific wind/snow load calculation per Eurocode EN 1991.