Rock Climbing Bolts : How Do They Work?

In Care & Maintenance, Good to Know, Pro Advice, Skills by Pete

Bolts: Who Places Them and How is it Done?

In a nutshell, a climbing bolt is literally a bolt that you screw into a rock face, and it serves as an anchor point for progressing in your climb.  If you learned to climb in a climbing gym or you’re accustomed to climbing at popular sport climbing areas with well-protected routes, then you might not spend much time thinking about the bolts you’re clipping or how they got there. As you start exploring more obscure climbing areas, breaking into trad climbing, or climbing in areas that were developed a long time ago, you’ll probably start to notice that there are a lot of different kinds of bolts out there and that some look different than others. Bolting practices have changed a lot over the years, and differ from climbing area to climbing area depending on the rock type, local ethics, and more. It’s important to know how bolts are placed so that you can tell a good bolt from a bad one, and it’s also cool to know more about bolt placement and route development because it can give you a new appreciation for the routes you climb when you understand their history and the work that went into putting up those routes.

retro climbers

Climbers from the 1970s, before bolting was common.  These are Stonemasters from Southern California

The History of Bolts

Climbers first started placing bolts sometime around the 1940s. Up until that point, climbs were protected by hammering in pitons or using chockstones or nuts, and many climbers looked down on the use of bolts long after their introduction into the climbing world. Most trad climbers and aid climbers continued to nail routes with pitons rather than placing bolts, but occasionally bolts were drilled as anchors on long routes or as a means to get past sections of blank face where nothing else would work. Bolts were the subject of lots of controversy in many of America’s classic climbing areas, and you can still see places where bolts have been chopped on routes where they were deemed unnecessary and therefore in poor style.

climbing bolts

A selection of bolts ready for use


The 1980s marked the beginning of sport climbing in America. Visionary climbers in Smith Rock began developing face climbs that could only be protected with drilled bolts since there were no cracks to nail or protect with gear. This new style of climbing sparked plenty of controversies, but nevertheless, it took off and became a hugely popular style of climbing in the 1990s, as up and coming professionals like Chris Sharma were pushing grades and climbing routes harder than anyone had ever believed was possible. New climbing areas were developing across the country where drilled bolts were the norm, and all different kinds of equipment was being installed in all kinds of ways. Without an organization (or the internet) to standardize the practice of bolt placement, people were learning as they went, and as a result, there was a lot of sketchy stuff going on.

Hardware Store Bolts?

Most climbers were buying equipment to bolt climbs from the hardware store and some were even designing the hangers themselves. A lot of the equipment was designed for construction purposes and didn’t stand up well to the elements, not to mention that most of the bolts were hand-drilled and shoved in there with little knowledge of how well they would stay in or stand the test of time. Even bolts that were totally bomber when they were originally placed might be 40 years old at this point, so it’s impossible to know what the part of the bolt inside the rock looks like now.

old rusty bolt

Hmm… not really sure what this bolt looks like inside. Is it safe?

Bolt Replacement

For quite a while it was considered poor practice to remove old fixed gear and replace it with modern equipment, but this mindset has gradually been shifting over the last few years. Todd Vogel wrote an excellent article in which he details this shift, explaining that at this point the original bolts on man classic routes have essentially expired, and it should no longer be considered unethical to replace equipment if it used to be solid but has degraded over time. He also explains how to determine which bolts ought to be replaced, and offers two cool visuals of a selection of bad bolts compared to a selection of solid bolts.

Modern Bolts

Today there is an industry standard when it comes to bolts, and anyone placing bolts should research these standards to find out which type of bolt is best for the area they are bolting. Generally speaking the standard choice for bolts are the Rawl 5 piece bolt in ⅜ or ½ inch width, and 3-6 inches in length depending on the rock type. In some areas with soft rock the standard is a glue-in bolt, and in some areas where the air is particularly moist or near saltwater you’ll need to consider the possibility of corrosion and will probably opt for stainless steel equipment.

Check out our #1 recommendation for a very high-quality bolt for your gear bag!

climbing bolt

A new modern bolt that has been recently placed. This one’s holding a water hose

Bolting Ethics

When it comes to bolting routes, there are different ethics and laws in place in different areas so you should always talk to locals and do your research before bolting a route in an area where climbing is already established. Never add a bolt to a previously established route without permission from the first ascensionist, and make sure that new route development is allowed before bolting new climbs. Every climbing area has their own standards and rules about bolting: some areas frown upon bolting on rappel, whereas in other areas it’s a totally common practice. Some areas allow the use of power drills, whereas all climbing areas in national parks require bolters to drill by hand. In some areas, it’s common to place a bolt every 7-10 feet for the whole climb, whereas in other areas climbers only place bolts to protect huge falls from the hardest moves, and sometimes not even then! The takeaway here should be that you should always ask locals before placing fixed gear because climbers take this stuff pretty seriously and if you bolt without asking and accidentally do it in a way that isn’t allowed in that area you are certain to piss people off.

If you’re developing a climb in a completely new area, there will be no current standard for that area. Before placing any bolts you should check with the landowner or agency to make sure that bolts are allowed, and if they are it’s up to you as a developer to decide what kind of bolting ethics to use in that particular area.

Petzl 2018 COEUR PULSE 12mm Removable anchor with locking function

The Petzl Pulse 12 -One of the newer bolts available on the market specifically for climbing (no hardware store re-rigs)

How to Place Bolts

The best way to learn how to place bolts is to find someone who’s experienced in it and have them show you. If this isn’t an option for you, the next best bet is to research the proper technique and then practice it on the ground. Follow the steps below on your practice run:

  1. Choose the right bolt for the rock type. Use this handy chart from the Access Fund to determine which kind of bolt you should use. Then cross-check your conclusion by consulting the locals to find out if the standard for that area is the same as the one you picked out from the chart.
  2. Choose your drill. If power drills are allowed and you’re not worried about weight you might go for the power drill, but consider bringing a hand drill as well in case your battery fails you.  You wouldn’t want to remove a bolt and then run out of battery before you could replace it! If power drills aren’t allowed then you’ll need a hand drill and a hammer. Climbing Magazine offers a great comparison on the pros and cons of power drills versus hand drills, which you can check out before you decide on one or the other.
  3. Choose where you want to place the bolt. The placement should depend on the quality of the rock, ease of placing and clipping, and usefulness. If you’re just practicing you only need to consider rock quality, which you can check visually as well as by feel. Knock on the rock and hit it lightly with a wrench to listen for hollowness. If you hear any hollow sounds, choose a more solid spot.
  4. Drill a hole using a drill bit that matches the diameter of your bolt. Your drilling technique will differ depending on whether you’re using a hand drill or a power drill, but the end product should be the same. Be careful to drill a consistent, clean hole that goes straight into the rock, and use a blow out bulb or length of thin tubing to blow dust out of the hole as you drill. For some seriously in-depth instructions, check out this awesome article from Tawkroc. Scroll down to Part 6, “Placing a Bolt” for a detailed, step by step breakdown of the drilling process.
  5. Insert the bolt into the hole. This part will also differ depending on the type of bolt you are using. so make sure you follow the directions for the bolt you’ve purchased. Always use the washer in addition to the hanger, and make sure you check the recommended torque for the bolt you’re using so you’ll know how hard to tighten it down.

Practice, Learn, Practice, Learn … and Repeat

This list should get you started on your bolt placing adventures, but keep in mind that when you place a bolt, you are taking on a lot of responsibility as future climbers will expect that bolt to protect them in a fall. While it is a recommended practice in climbing to evaluate every bolt you clip and determine for yourself whether or not it is a good bolt, the reality is that most climbers don’t do this, so if you place a bad bolt the consequences could be serious. I would recommend finding a mentor to teach you how to bolt and watch you for the first few times so that you know you’re doing everything right, but if that’s not an option it is possible to learn for yourself as long as you are diligent and careful and take the time to practice. Many climbing areas have groups of locals that go out on a regular basis to replace old bolts, and many of these groups receive funding or equipment from the ASCA. Joining one of these groups for a few outings is a great way to learn how to place bolts as well as to give back to your local climbing area.

Rock Climbing Bolts : How Do They Work? was last modified: April 27th, 2019 by Pete