Slotted Perforated Metal Overview
Slotted perforated metal is sheet metal punched with elongated openings rather than conventional round holes.
The slot length, width, spacing and direction can be customized to control airflow, drainage, screening performance and visual appearance. Depending on the application, slots can be arranged in straight, staggered or project-specific patterns.
Slotted perforated sheet metal is commonly selected where an elongated opening provides better flow, drainage or separation than a circular perforation.
Slotted Perforated Metal Sizes and Specifications
The key dimensions for slotted hole perforated metal are slot width, slot length, pitch, orientation and open area.
| Specification | Available Options | Selection Notes |
|---|---|---|
| Material | Stainless steel, aluminum, carbon steel, galvanized steel | Select according to corrosion resistance, strength and weight |
| Sheet Thickness | According to project requirements | Should be considered together with slot width and panel size |
| Slot Width | Custom opening width | Influences screening accuracy and drainage performance |
| Slot Length | Custom elongated opening length | Influences flow direction and open area |
| Slot Shape | Round-end, square-end or available custom geometry | Confirm required slot geometry before production |
| Pitch | Custom center-to-center spacing | Controls slot density and remaining metal |
| Slot Arrangement | Straight, staggered or custom layout | Influences appearance, open area and panel behavior |
| Slot Direction | Parallel or transverse to sheet length | Important for drainage, flow and finished appearance |
| Open Area | Customized percentage | Balance flow performance with sheet rigidity |
| Sheet Size | Standard or custom width and length | Provide finished dimensions where possible |
| Perforation Layout | Full, partial or custom perforation | Solid areas can be retained for mounting or forming |
| Solid Border | Optional perimeter or local zones | Useful for fixing, bending and framing |
| Surface Finish | Mill finish, polished, galvanized, painted or powder-coated | Select according to material and environment |
| Fabrication | Cutting, bending, forming and framing | Available according to drawings |
| Tolerance | According to slot and finished sheet requirements | Critical dimensions should be identified before production |
How to Select Slotted Perforated Metal
The slot geometry should be selected according to what the finished sheet needs to pass, retain, drain or ventilate.
Slot Width
Slot width is usually the most important dimension for screening and separation because it determines the minimum opening across the sheet.
Slot Length
Longer slots can increase open area and provide greater flow capacity while maintaining a relatively narrow opening width.
Slot Direction
Slot orientation can influence drainage, airflow and the visual direction of the finished panel. The required direction should be shown clearly on drawings.
Open Area
Higher open area generally improves airflow or drainage, but reducing the amount of remaining metal can also affect panel rigidity.
Slotted Perforated Metal Materials
Stainless Steel Perforated Metal
Stainless steel provides excellent corrosion resistance and are suitable for demanding environments.
Aluminum Perforated Metal
Aluminum offers lightweight construction and natural corrosion resistance.
Carbon Steel Perforated Metal
Carbon steel provides strength and cost efficiency for general industrial fabrication.
Galvanized Perforated Metal
Galvanized provides additional corrosion protection for outdoor and exposed applications.
Slotted Perforated Metal Applications
Perforated Metal Filtration & Screening
Gutter Guards & Drain Covers
Industrial Screening & Sieving
Perforated Metal Railings & Privacy Screens
Custom Slotted Perforated Metal Fabrication
Slotted perforated sheets can be supplied as raw sheets or fabricated into finished components.
Cutting & Sizing
Sheets can be cut to finished widths, lengths and custom shapes.
Bending & Forming
Slotted sheets can be formed into screens, drainage parts, covers and fabricated panels.
Borders & Mounting
Solid borders, fixing holes and non-perforated mounting zones can be retained according to drawings.
Surface Finishing
Galvanizing, polishing, painting and powder coating are available according to material and application requirements.

How to Order Slotted Perforated Metal
Material
Specify stainless steel, aluminum, carbon steel or galvanized steel.
Slot Thickness & Size
Provide the required base material thickness. Specify slot width × slot length.
Pitch & Arrangement
Provide slot spacing and whether the pattern is straight, staggered or customized.
Slot Direction
Confirm slot orientation relative to the sheet length or installation direction.
Sheet Size & Quantity
Provide finished width, length and required quantity.
Finish & Fabrication
Specify solid borders, bending, cutting, mounting holes and required surface finish.
For custom projects, CAD or PDF drawings are recommended before quotation.
Case Study : Slotted Drainage Covers for a Public Plaza
Project Requirement
A landscape contractor required custom metal drainage covers for paved pedestrian areas around a public plaza.
The covers needed to allow rainwater to drain efficiently while reducing the entry of leaves and larger debris. The visible surface also needed a clean, consistent appearance across multiple drainage sections.
Manufacturing Solution
Stainless steel slotted perforated metal was selected for outdoor corrosion resistance and ease of maintenance.
The slot width was selected according to the required debris restriction, while slot length and spacing were adjusted to provide the required drainage area.
Slots were oriented parallel to the drainage direction, with solid perimeter zones retained for forming and mounting.
The sheets were cut to finished dimensions and formed into removable cover sections according to the contractor’s drawings.
Inspection & Packaging
Slot dimensions, spacing, panel size, formed edges and mounting locations were checked before shipment.
Finished covers were grouped by installation area and protected with separators during packing.
Slotted Perforated Metal FAQs
Slotted perforated metal is sheet metal punched with elongated openings rather than circular holes.
The main dimensions are slot width, slot length and the spacing between adjacent openings.
Straight, staggered and custom layouts can be manufactured according to production capability and project drawings.
Yes. Slots can be oriented according to drainage, airflow, screening or visual requirements.
Open area depends on slot width, length, pitch and arrangement.
Common materials include stainless steel, aluminum, carbon steel and galvanized steel.
Yes. Non-perforated borders can be left around edges, mounting locations and forming zones.
Yes. Cutting, bending, forming and framing can be completed according to drawings.
Related Perforated Metal Products
Explore other perforated metal products with different sheet forms, screening functions and hole patterns for industrial, architectural and custom fabrication requirements.
Perforated Metal Sheet
Perforated metal sheets with customizable materials, thicknesses, hole sizes and open areas for further fabrication and general applications.
Perforated Metal Panels
Finished perforated panels for architectural walls, facades, ceilings and project installations.
Perforated Metal Screen
Perforated screen panels for privacy, ventilation, security and separation applications.
Hexagonal Perforated Metal
Six-sided perforations for geometric appearance, ventilation and screening.
Round Hole Perforated Metal
Circular perforations for ventilation, filtration and general screening.
Square Perforated Metal
Square perforated metal offers a clean geometric pattern for industrial and architectural applications.
Corrugated Perforated Metal Panels
Profiled perforated panels providing increased rigidity and a three-dimensional surface.
Micro-Perforated Metal
Micro-perforated metal provides fine openings for acoustic, filtration and specialized applications.