TechFast vs. Concrete Screws: The Pro's Guide to Faster Fixings
In the glazing and construction trade, time is the most expensive commodity on any job site. If you are still using traditional plastic wall plugs and standard woodscrews to secure window frames, you are losing hours of billable time every week.
The industry has moved toward Direct Fixings, specifically TechFast Window Screws and Concrete Frame Screws. Both technologies are designed to eliminate the need for secondary components like wall plugs, allowing for a faster, cleaner, and more secure installation. However, while they both belong in a professional’s van, they serve entirely different purposes.
This guide breaks down the technical specifications, applications, and advantages of these two essential fixings so you can choose the right one for your next install.
What are TechFast Window Screws?
TechFast is a specialized brand of self-drilling and self-tapping screws primarily used within the window and door industry. Their primary function is to secure hardware, such as hinges, friction stays, and handles, directly into the metal-reinforced sections of a PVCu frame.
Technical Specifications
- Diameter: Typically 3.9mm to 4.8mm.
- Length: Commonly found in 13mm, 19mm, 25mm, and 38mm lengths.
- Tip Design: Features a self-drilling point (similar to a drill bit) that can penetrate up to 2.5mm of steel reinforcement without a pilot hole.
- Coating: Usually zinc-plated for corrosion resistance, passing the 100-hour salt spray test.
Why use TechFast?
The standout feature of a TechFast screw is its ability to bypass the pre-drilling stage. When you are fixing a friction stay to a reinforced window profile, a standard screw would require you to drill the metal first. A TechFast screw drills its own hole and taps its own thread in one fluid motion. This significantly reduces the risk of the screw "skating" across the surface of the hardware.
What are Concrete Frame Screws?
While TechFast handles the internal hardware, Concrete Frame Screws (often called masonry screws or starform screws) handle the heavy lifting of securing the actual window frame to the building substrate.
Technical Specifications
- Diameter: Almost universally 7.5mm.
- Length: Ranges from 42mm up to 202mm, with 82mm and 102mm being the trade standards for window installation.
- Thread: Features a high-low thread design that cuts deeply into masonry, brick, and concrete.
- Drive: Typically uses a Torx (T30) drive to prevent cam-out under high torque.
Why use Concrete Screws?
The "Concrete Screw" replaced the old-fashioned frame anchor (the nylon sleeve with a screw inside). Because the screw taps directly into the brick or concrete, there is no expansion force like you get with a plastic plug. This means you can fix windows closer to the edge of the brickwork without the risk of splitting the masonry.
Why the "No Plug" Revolution Saves You Money
Both TechFast and Concrete Screws are "Direct Fixings." By removing the need for a wall plug or a pre-drilled metal hole, you realize three immediate benefits:
- Reduced Labour Time: Every hole you don't have to drill or plug you don't have to hammer in saves roughly 30 to 60 seconds. On a full house of windows, that adds up to over an hour of saved time.
- Lower Material Costs: You no longer need to stock multiple sizes of wall plugs. You also reduce the wear and tear on your drill bits, as the TechFast screws handle the metal penetration themselves.
- Superior Pull-Out Strength: A direct thread-to-substrate connection is inherently more stable than a screw-to-plastic-to-brick connection.
Pro Tip: Choosing the Right Bit
Always use a T30 Torx bit for 7.5mm concrete screws. Using a standard Pozi or a smaller Torx bit will result in "cam-out," stripping the screw head and leaving you with a half-driven fixing that is nearly impossible to remove.
Technical Comparison: TechFast vs. Concrete Screws
| Feature | TechFast Window Screws | Concrete Frame Screws |
|---|---|---|
| Primary Substrate | Metal-reinforced PVCu | Brick, Concrete, Stone, Block |
| Installation Tool | Impact Driver / Drill Driver | Impact Driver (preferred) |
| Pilot Hole Required? | No (Self-drilling) | Yes (Typically 6mm or 6.5mm) |
| Typical Drive Type | Phillips (PH2) or Torx | Torx T30 |
| Diameter | 3.9mm | 7.5mm |
| Typical Usage | Hinges, Handles, Cills | Frame to Wall Fixing |
How to Install: Step-by-Step
1. Using TechFast for Hardware
- Align your hardware (e.g., a friction stay) onto the PVCu profile.
- Set your drill driver to a medium torque setting to avoid over-tightening.
- Apply firm pressure and drive the TechFast screw through the hardware hole.
- The screw will drill through the outer PVCu and into the internal steel reinforcement.
- Stop immediately once the head is flush to avoid stripping the thread in the metal.
2. Using Concrete Screws for Frame Fixing
- Position your window frame in the opening, ensuring it is level using glazing packers.
- Drill a 6mm or 6.5mm pilot hole through the frame and into the masonry. Ensure the hole in the masonry is at least 10mm deeper than the screw length to allow for dust.
- Clear the dust from the hole if possible (or "pump" the drill bit).
- Drive the 7.5mm Concrete Screw directly through the frame into the wall.
- The high-low thread will cut into the brick, creating a permanent, non-expansion fixing.
Factors to Consider: Substrate and Loading
While these screws are revolutionary, they aren't magic. You must consider the material you are fixing into:
- Engineering Brick: You may need a 6.5mm pilot hole for concrete screws instead of the standard 6.0mm to prevent the screw from snapping due to the density of the brick.
- Aerated Block: Concrete screws work exceptionally well here, but avoid over-torquing, as the soft material can strip easily.
- Reinforcement Thickness: TechFast screws are rated for specific metal thicknesses (usually up to 2.5mm). If you are fixing into heavy-duty structural steel, you may need a heavy-section self-driller.
Frequently Asked Questions
Can I use TechFast screws in brick?
No. TechFast window screws are designed for metal and PVCu. They do not have the thread depth or the hardness required to cut into masonry. If you try, the tip will burn out, and the screw will fail.
Do I need to use a sealant with these screws?
Yes, particularly for Concrete Frame Screws that penetrate the outer perimeter of the window frame. Always apply a dab of high-quality silicone over the screw head (or use a dedicated cover cap) to prevent water ingress into the frame chamber.
Why do my concrete screws keep snapping?
This usually happens for two reasons: the pilot hole is too small for the substrate (e.g., 6mm in very hard concrete) or the hole isn't deep enough. If the screw hits a "bottom" of dust, the torque will spike and snap the head. Always drill deeper than you need.
Are these screws reusable?
Concrete screws can be removed and re-inserted into the same hole, but they will have slightly less grip the second time. TechFast screws are best used once, as the self-drilling tip dulls after the first use.
Get the Right Gear for the Job
Don't let poor-quality fixings slow down your installs. At Glazing Supplies Direct, we stock a full range of trade-approved TechFast window screws and Concrete Frame Screws in the sizes you need most. Whether you’re a pro glazier or a DIYer tackling a home upgrade, we provide the same high-quality materials used by the biggest names in the industry.
Why buy from us?
- Trade Quality: No cheap imitations: only tested, reliable fixings.
- No Trade Account Required: Everyone gets competitive prices from day one.
- Free UK Delivery: Spend over £50 and we’ll ship it for free.
- Fast Turnaround: Next-day delivery available on in-stock items.
Shop our range of Screws and Fixings today and experience the "No Plug" difference on your next project.
