Description
Reveals, soffits and open wall fields all end up carrying something small — a house number, a bell push, a sensor bracket — and on a finished insulated facade there is no masonry within reach to fix it to. The WK-DS050 answers that, and it is stocked at Renders World inside the EWI insulation fixing accessories range.
What the WK-DS050 Spiral Anchor Holds on a Rendered Insulated Wall
The WK-DS050 spiral anchor is a 50 mm polyamide fastener rated by Klimas for lightweight non-structural fittings up to 5 kg per piece on polystyrene insulation walls, which covers most of what a facade carries.
Klimas names the fittings it is intended for — signboards, building numbers, mailboxes, lighting fixtures and motion sensors. Because the helix is screwed into the insulation layer itself, the data sheet states that the fastener keeps the continuity of the thermal insulation at the installation spot and eliminates a thermal bridge there, which is why it is chosen ahead of a through-fixing for anything this light.
- Substrate — polystyrene insulation walls, the scope the manufacturer states; the fastener does not reach or rely on the masonry behind.
- Load — up to 5 kg per fastener, non-structural, which is the accessory schedule most houses need after the render has gone on.
- Material — polyamide, specified by Klimas for resistance to changing weather conditions on an external wall.
Why Installers Choose the WK-DS050 for Light Facade Fittings
- No thermal bridge at the fixing point — the sheet states the fastener maintains insulation continuity where it is installed, so a bell push does not introduce a cold path through the build-up.
- One drive, one tool — a screw gun with a TORX-30 bit sets the fastener; nothing else is needed at the wall.
- A 28 mm plate — the load is spread across the plate diameter rather than concentrated on a single screw shank in soft insulation.
- A single screw size to order — the sheet specifies Ø 4.5 mm, not supplied with the pack, so the screw is a deliberate purchase rather than a guess at the merchant's counter.
- Sold in tens — a 10-piece box suits the handful of fixing points a finished elevation actually needs, and the pack is easy to price into a schedule.
WK-DS050 Technical Specifications, Read From the Klimas Data Sheet
| Property | Value |
|---|---|
| Product code | WK-DS050 |
| Manufacturer | Klimas Sp. z o.o. (Wkręt-met) |
| Fastener length | 50 mm |
| Plate diameter | 28 mm |
| Socket type | TORX-30 |
| Screw diameter | 4.5 mm, not supplied |
| Material | Polyamide |
| Maximum load | 5 kg per piece, non-structural |
| Stated substrate | Polystyrene insulation walls |
| Pack quantity | 10 pcs |
Worth knowing before ordering: the Klimas sheet publishes a fastener length and no length-to-board-thickness table. The fastener is screwed into the thermal insulation layer, so the depth of insulation at the mounting point is the figure to confirm on site — the sheet will not settle it, and neither will arithmetic.
How to Install the WK-DS050: Two Sequences the Manufacturer Recognises
Klimas recommends two routes, and which one applies depends on when the fixing positions are known. Where they are known before the reinforced layer goes on, the fastener is screwed into the insulation before the adhesive and reinforcing mesh are applied. On a wall that is already finished, the sheet directs you to drill through the applied adhesive, mesh and plaster with a drill bit for concrete first, then screw the fastener into the insulation behind — the render coat is drilled, not driven through.
- Mark the installation positions on the facade before starting.
- Either screw the fastener in before the adhesive and mesh, or drill the finished adhesive, mesh and plaster with a concrete bit at each mark.
- Drive the fastener into the insulation with a screw gun and a TORX-30 bit until the plate is seated flush.
- Fix the item with a Ø 4.5 mm screw, bought separately and sized to the thickness of what is being mounted.
Trade practice adds one thing the sheet leaves to you: use stainless steel for the screw on any external position, since a plated steel head sits proud in the weather where the fitting is most visible. The same properties make this a straightforward spiral anchor for insulation repair work, where a light fitting is being remounted on an existing rendered elevation rather than specified into a new build-up. For where mechanical fixings sit in the wider system, the EWI fixings installation guide sets out the full method, and board plugs and their layout belong with the fixing pattern and spacing guide.
Choosing Between the 50 mm and 85 mm Spiral Anchor
Klimas publishes both sizes of WK-DS on one data sheet, and every declared parameter except length is shared. That makes the choice a single question about the insulation depth at the fixing point.
| Parameter | WK-DS050 (this pack) | WK-DS085 |
|---|---|---|
| Fastener length | 50 mm | 85 mm |
| Plate diameter | 28 mm | 28 mm |
| Socket | TORX-30 | TORX-30 |
| Screw | 4.5 mm, not supplied | 4.5 mm, not supplied |
| Maximum load | 5 kg, non-structural | 5 kg, non-structural |
| Pack | 10 pcs | 10 pcs, 85 mm variant |
Since the load rating and the plate are identical, neither size is the stronger fixing — the longer body simply engages more insulation where more insulation is there to engage.
Ordering the WK-DS050: Pack Price and What Else to Add
Renders World lists the 10-piece pack at £4.99, August 2026, and the product endpoint reports it available at the same fetch. Per fixing point that is £4.99 ÷ 10 = £0.50 per anchor, before the screw.
- Screws — one 4.5 mm screw per fastener, not in the box, length set by the item being mounted.
- Quantity — count the fixing points on the elevation, since each mounted item takes one or more; the pack of ten prices cleanly against that count.
- Length — confirm the insulation depth at each position before choosing between the 50 mm and 85 mm bodies.
Is the WK-DS050 the Right Fixing for Your Detail?
- Light fittings on a polystyrene-insulated wall — this is the stated application: up to 5 kg, non-structural, on the polystyrene boards from the graphite EPS insulation boards range.
- Deeper insulation at the fixing point — the 85 mm WK-DS085 spiral anchor carries the same plate, socket, screw size and 5 kg rating with a longer body.
- Shutters, blinds, awnings and anything structural — specify a through-fixing to the substrate for these; Klimas states the WK-DS is for lightweight non-structural components, which is where it performs best.
- Stone wool linings — the sheet's stated substrate is polystyrene, so slabs from the mineral wool insulation range fall outside its scope and need a fixing declared for wool.
- Trade schedules — the Renders World desk will size anchor packs, screw diameters and lengths against an accessory list before a purchase order goes in.
FAQ — WK-DS050 Load Limits, Screws and Compatibility
Is the screw included in the pack? No. The box holds ten polyamide fasteners, and the data sheet specifies a Ø 4.5 mm screw that is not supplied. Order the screws alongside the pack, in stainless steel for external positions.
How many packs will a job need? Work from fixing points rather than from a house, because the schedule varies with what is being mounted. A quick way to arrive at it:
- List the items going onto the finished facade.
- Count the fixing points each one takes.
- Divide the total by the ten fasteners in a pack.
What load can one fastener take? Up to 5 kg per piece, and only for non-structural components. Items exposed to large dynamic forces — shutters, blinds and shades are the manufacturer's own examples — take a through-fixing to the substrate instead.
Which size suits my build-up, 50 mm or 85 mm? Both share the plate, socket, screw size and load rating, so the answer follows the insulation depth at the mounting position. Klimas publishes no length-to-thickness table, so confirm the depth on site or at design stage rather than assuming from a board schedule.
Does the plate accept a render or paint finish? The sheet is silent on overcoating, so treat a patched-out fastener as a finishing question for the render manufacturer rather than a stated property of the fixing. Where a head is to be concealed, agree the make-good with the render supplier first.
Technical Documentation for the WK-DS050
- Klimas WK-DS product page and data sheet download — sizes, application and technical parameters, fetched August 2026.