Simpson Strong-Tie Deck Screws, Titen HD Anchors, and Allen Drive Cap Screws: A Field Guide

I'm not a structural engineer. I'm the person who checks the small print on fasteners before they go to a job site. At our shop, I review around 150 product lots a year, and in 2024 I rejected seven of them because the documentation didn't match the label.

One thing I've learned is that there's no single Simpson Strong-Tie product that answer every question. The right deck screw is not the same as the right Titen HD anchor, and the right Allen drive cap screw is not the same as whatever screw is lying in the trailer. This guide is how I sort through those calls.

Start With the Label, Not the Internet

When someone asks me which fastener to use, I don't start with a price list. I start with three questions:

• Is this a structural connection or just positioning?
• What is the base material: wood, concrete, masonry, or steel?
• Is the fastener rated for the environment on the project?

If a fastener isn't rated for what it's doing, the size chart doesn't matter. The label is the spec.

Simpson Strong-Tie Deck Screws: One Size Does Not Work

Here's something that surprises a lot of contractors: “Simpson Strong-Tie deck screws” is not one product line. There are wood-to-wood screws, composite deck screws, stainless steel screws, and structural screws that go into joist hangers. They are not interchangeable.

For wood deck boards over wood joists, I usually look for a coated structural wood screw with enough length to get into the joist. For composite or PVC decking, I want a screw designed for composite. Composite boards expand and contract more than wood, and a screw with the wrong thread profile can either loosen or crack the board near the edge.

The biggest issue I see on site is not the screw brand. It's how fast the screw gets driven. If you run a full-trigger impact into dense wood, the head can seat and strip before you feel it. When the head touches the board, stop. That last half-turn is where deck screws fail.

Simpson Strong-Tie Titen HD Screw Anchor vs. the Anchor Bolt Size Chart

One question I get a lot is whether to use a Simpson Strong-Tie Titen HD screw anchor or a wedge anchor. The honest answer: it depends on the concrete and the load.

I've seen wedge anchors installed in cracked concrete when the inspector required an anchor with a current evaluation report for cracked concrete. The wedge anchor might hold in a basic pull test, but that doesn't make it the right call. The Titen HD screw anchor is often a better fit because Simpson Strong-Tie has published data for cracked and uncracked concrete conditions. But that doesn't mean it's always the cheapest way to do the job.

Before you pull up an anchor bolt size chart, stop. A generic chart tells you bolt diameter. It doesn't tell you embedment depth, edge distance, or concrete strength, and those are the numbers that make the difference.

I remember checking 5/8-inch anchors for a steel threshold replacement. The old spec said 5/8-inch, so the contractor ordered 5/8-inch. The slab was only four inches thick in one section, and the required embedment wasn't there. Looking back, I should have flagged that before the order. At the time, everyone just matched the bolt diameter.

So when someone asks me about anchor bolt size, I tell them: get the current Simpson Strong-Tie technical data sheet, read the footnotes, and verify the concrete condition before choosing. A smaller anchor with enough embedment is usually better than a bigger anchor that can't get deep enough.

Allen Drive Cap Screws and Steel Connectors

Allen drive cap screws show up in connector hardware lists more often than most people expect. These are not decorative bolts. The socket head cap screw is part of the connection, and the type, size, and thread length are usually specified on the connector drawing.

What I see in the field: someone looks at a bracket, says “that looks like a 1/4-inch screw,” and grabs the nearest cap screw from the job box. That substitution is exactly what creates the quality issue I get called about later.

Use the screw the connector manufacturer lists. If the drawing says Allen drive cap screw, make sure the drive is clean and the Allen bit is fully seated. A worn ball-end Allen bit will round out the socket before you hit the right torque. Replace the bit. It's cheap.

And if you're dealing with steel-to-steel connections, don't assume a longer cap screw is safer. The thread may bottom out, or the bearing surface may be wrong.

How to Change the Disc on an Angle Grinder

This seems unrelated, but it comes up all the time. A grinding disc fails on a job, and then the next thing I see is a cutoff plate with a damaged slot because the saw was struggling. Replacing the disc on an angle grinder is part of quality work, not just a maintenance step.

Here's what I tell everyone who works around our fasteners and anchors:

1. Unplug the grinder or remove the battery. Do it before anything else.
2. Press the spindle lock and rotate the disc until it engages.
3. Loosen the nut with the correct wrench. Different grinders use different thread directions, so check the guard or manual before forcing it.
4. Look at the disc before installing it. No cracks, no damp spots, no chips around the edge.
5. Make sure the new disc is rated for the grinder's maximum RPM. That number is printed on the disc.
6. Tighten the nut firmly, not with a pipe wrench, and keep the guard on.

A clean cut on an anchor plate or a top plate matters. A notched edge or a torn hole can create a stress point. Changing the disc on an angle grinder is a 60-second job if you do it calmly, and it prevents the kind of shortcuts that show up in a final inspection.

So Which Situation Are You In?

If you're still trying to pick between deck screws, anchors, and cap screws, here's my rule:

• If it's part of a load-rated connector, follow the connector drawing exactly. No improvisation.
• If it's going into concrete or masonry, use an anchor with published data for your concrete condition and install it per the current technical sheet.
• If it's a wood-to-wood screw, use a rated screw with the right coating, and control the driving speed.

Also, think about schedule risk. I've seen cheap online anchors save $40 and cost $300 in waiting time. The premium for a fastener you can have in hand today, with the data sheet in your email, is worth it when the pour is tomorrow. That's not about buying expensive hardware. It's about buying certainty.

When in doubt, take a picture of the label and send it to the engineer before you substitute anything. I'm not the engineer who stamps the drawing, but I'm the one who sends back the parts that don't match it.