Choosing the right self-drilling roofing screws in Kenya is essential for a secure, leak-free, and long-lasting roof. This guide explains roofing screw sizes, EPDM washers, proper installation torque, and common installation mistakes to help homeowners, contractors, and builders achieve durable roofing performance in Kenya's diverse climate.
When installing a new roof, many people focus on choosing quality roofing sheets while overlooking one of the most important components—the roofing screws. Even the strongest roofing sheets can develop leaks, loosen over time, or fail during strong winds if the wrong fasteners are used.
Choosing the correct self-drilling roofing screws in Kenya ensures your roof remains secure, weatherproof, and durable for years. Whether you're installing corrugated mabati, box profile sheets, stone-coated roofing tiles, or polycarbonate roofing, using the right fasteners makes all the difference.
Ali Glaziers Roofing Division stocks premium Roofing Screws & Fasteners designed for Kenya's diverse weather conditions, helping homeowners, contractors, and developers achieve professional, long-lasting roofing installations.
This guide explains roofing screw sizes, EPDM sealing washers, installation torque, and best practices to ensure your roofing project stands the test of time.
What Are Self-Drilling Roofing Screws?
Self-drilling roofing screws are specially engineered fasteners with a built-in drill point that penetrates roofing sheets without requiring a pilot hole.
Unlike ordinary wood screws or roofing nails, they are specifically manufactured for roofing applications because they provide:
- Faster installation
- Superior holding strength
- Excellent waterproof sealing
- Better wind resistance
- Easier maintenance and replacement
A typical roofing screw consists of:
- Hardened steel body
- Corrosion-resistant coating
- Self-drilling tip
- Hexagonal drive head
- Bonded EPDM sealing washer
Together, these components create a secure and watertight roofing system.
Why Roofing Screws Are Better Than Roofing Nails
Modern roofing projects increasingly use self-drilling screws because they outperform traditional roofing nails in several important ways.
1. Stronger Holding Power
Threaded screws grip timber or steel framing more securely, reducing the chances of roofing sheets lifting during:
- Heavy winds
- Storms
- Thermal expansion
- Structural movement
2. Better Waterproofing
Each roofing screw includes an EPDM sealing washer that compresses against the roofing sheet to create a watertight seal around every fixing point.
3. Easier Future Repairs
Unlike nails, roofing screws can be removed and replaced without damaging the roofing sheets, making maintenance much easier.
Common Types of Self-Drilling Roofing Screws in Kenya
Different roofing projects require different types of fasteners.
Timber-to-Roofing Screws
These screws are designed for fixing roofing sheets onto timber rafters and are commonly used in:
- Residential homes
- Pergolas
- Carports
- Farm structures
Steel-to-Steel Roofing Screws
Designed with stronger drill points, these screws penetrate steel purlins and are widely used for:
- Commercial buildings
- Warehouses
- Industrial roofing
- Steel frame construction
Stitching Screws
Stitching screws fasten overlapping roofing sheets together, improving wind resistance and structural stability.
Common Roofing Screw Sizes in Kenya
Choosing the correct screw length depends on:
- Roofing sheet profile
- Supporting framework
- Insulation thickness
- Roof design
| Roofing ApplicationCommon Screw Length | |
| Corrugated sheets to timber | 50 mm |
| Box profile sheets | 65 mm |
| Ridge cap installation | 75–100 mm |
| Insulated roofing systems | 100–150 mm |
| Sheet overlap stitching | 20–25 mm |
Longer screws are necessary whenever insulation or thicker roofing materials are used.
Understanding EPDM Washers
An EPDM washer is one of the most important components of a roofing screw.
Each washer consists of:
- Galvanized steel backing washer
- EPDM rubber sealing ring
The steel provides clamping pressure, while the EPDM rubber forms a weatherproof seal around the screw hole.
Why EPDM Rubber Performs Better
EPDM rubber is specifically designed for outdoor roofing applications.
It offers excellent resistance against:
- UV radiation
- Heat
- Rain
- Ozone
- Temperature changes
Unlike ordinary rubber, EPDM remains flexible for years without cracking, shrinking, or hardening.
This helps maintain a leak-free roof throughout its lifespan.
Why Correct Installation Torque Matters
Even premium roofing screws can fail if installed incorrectly.
Over-Tightening
Applying excessive torque can:
- Crush the EPDM washer
- Split the rubber seal
- Deform roofing sheets
- Reduce waterproof performance
Under-Tightening
Insufficient tightening can lead to:
- Water leaks
- Loose roofing sheets
- Wind vibration
- Reduced holding strength
Correct Installation
A properly installed roofing screw should:
- Sit squarely on the roofing sheet
- Compress the EPDM washer slightly
- Leave the washer visible around its edge
- Avoid denting or deforming the roofing sheet
Correct installation provides maximum weather protection and extends roof life.
Choosing the Right Roofing Screw for Different Roofing Systems
Corrugated Roofing Sheets
Corrugated roofing sheets generally require medium-length screws installed through the crest of the roofing profile.
If you're installing new roofing, browse our premium Corrugated Roofing Sheets, designed for excellent weather resistance and compatibility with quality roofing fasteners.
Box Profile Roofing
Because box profile roofing has a higher rib profile, longer roofing screws are typically required to achieve a secure fixing.
Our range of Box Profile Mabati Sheets offers durable roofing solutions suitable for residential, commercial, and industrial projects across Kenya.
Stone Coated Roofing Tiles
Stone-coated roofing systems often require specialized fasteners depending on the manufacturer's specifications.
Explore our premium collection of Stone Coated Roofing Tiles, combining outstanding durability with the elegant appearance of traditional roof tiles.
Polycarbonate Roofing Sheets
Transparent roofing requires compatible roofing screws fitted with sealing washers that allow for thermal expansion without damaging the sheets.
Ali Glaziers supplies high-quality Polycarbonate Roofing Sheets that are ideal for skylights, pergolas, patios, greenhouses, and commercial roofing applications.
Common Mistakes When Installing Roofing Screws
Avoid these common installation errors:
Using Ordinary Construction Screws
General-purpose screws are not designed for roofing and lack weather-resistant sealing.
Reusing Old Washers
Old EPDM washers lose elasticity over time and should always be replaced.
Using the Wrong Screw Length
Short screws provide poor anchorage, while excessively long screws complicate installation without improving performance.
Driving Screws at an Angle
Misaligned screws prevent the washer from sealing properly, increasing the risk of leaks.
Choosing Low-Quality Fasteners
Cheap screws often have poor corrosion resistance, particularly in Kenya's humid coastal environments.
Roofing Screw Considerations Across Kenya
Nairobi
Roofing systems should withstand seasonal rainfall while accommodating daily temperature fluctuations.
Mombasa and Coastal Kenya
High humidity and salty air require corrosion-resistant roofing screws with quality protective coatings.
Kisumu
Frequent rainfall makes watertight sealing around every fixing point essential.
Nakuru and Eldoret
Temperature changes cause roofing materials to expand and contract, making secure fasteners especially important.
Long-Term Benefits of Quality Roofing Screws
Investing in premium self-drilling roofing screws provides:
- Better waterproofing
- Stronger wind resistance
- Longer roof lifespan
- Lower maintenance costs
- Faster installation
- Improved structural stability
- Enhanced corrosion protection
- Greater long-term value
Combined with quality roofing sheets and professional installation, the right fasteners significantly improve the overall performance of your roof.
Professional Roofing Advice
Every roofing project should be viewed as a complete system rather than a collection of individual materials.
The best results come from combining:
- High-quality roofing sheets
- Premium self-drilling roofing screws
- EPDM sealing washers
- Proper screw spacing
- Correct installation torque
- Professional workmanship
Ali Glaziers Roofing Division supplies complete roofing systems, accessories, and expert guidance for residential, commercial, and industrial projects throughout Nairobi, Mombasa, Kisumu, Nakuru, Eldoret, and the rest of Kenya.
Frequently Asked Questions About Self-Drilling Roofing Screws in Kenya
What are self-drilling roofing screws?
They are roofing fasteners with built-in drill points that eliminate the need for pre-drilling while providing strong, weather-resistant connections.
What does an EPDM washer do?
An EPDM washer creates a waterproof seal around the screw hole, preventing rainwater from entering the roof while resisting UV rays and weathering.
Which roofing screw size should I choose?
The appropriate screw length depends on the roofing profile, supporting structure, and insulation thickness. Most roofing projects use screws ranging from 50 mm to 150 mm.
Can roofing screws be reused?
It is always recommended to install new roofing screws and EPDM washers during repairs to maintain a proper weather seal.
Why do roofing screws leak?
Leaks usually occur because of:
- Over-tightening
- Under-tightening
- Damaged washers
- Incorrect installation angle
- Low-quality fasteners
Are roofing screws better than roofing nails?
Yes. Roofing screws provide stronger holding power, superior waterproofing, better wind resistance, and easier maintenance than traditional roofing nails.
Does Ali Glaziers supply roofing screws?
Yes. Ali Glaziers Roofing Division supplies premium roofing screws, roofing accessories, and complete roofing systems suitable for projects across Kenya.
Conclusion: Invest in the Right Roofing Fasteners
Choosing the correct self-drilling roofing screws in Kenya is just as important as selecting premium roofing sheets. Correct screw sizes, durable EPDM washers, corrosion-resistant coatings, and proper installation torque all contribute to a secure, leak-free, and long-lasting roofing system.
Whether you're building a new home, replacing mabati, or managing a commercial roofing project, investing in high-quality roofing fasteners helps protect your property from Kenya's demanding weather while reducing future maintenance costs.
Ali Glaziers Roofing Division provides premium roofing accessories, roofing sheets, and expert guidance to help every project achieve professional, long-lasting results.
Upgrade Your Roofing System with Ali Glaziers Today!
Whether you're a homeowner replacing iron sheets, a contractor managing a commercial development, or an architect designing a modern building, Ali Glaziers Roofing Division has the roofing products and accessories you need.
Why Choose Ali Glaziers?
- Premium self-drilling roofing screws with EPDM washers
- Durable roofing sheets and accessories
- Expert technical guidance
- Competitive prices
- Fast nationwide delivery across Nairobi, Mombasa, Kisumu, Nakuru, Eldoret, and beyond
Visit Us:
Funzi Road Branch, End of Funzi Road, Industrial Area – Ali Glaziers LTD Building, Nairobi
Call/WhatsApp: +254 (0) 716 259 682 | +254 (0) 722 522 452
Email: info@aliglaziers.com
Shop Online: https://roofing.aliglaziers.com/shop
