1. A Quality Barbell
If you're not lifting a barbell, then you're not serious about increasing strength. I use a Texas Power Bar for all my lifts. It costs about $300 with shipping, and the capacity is rated at 1500lbs which far exceeds what I'll ever be able to lift. Don't buy the cheap barbells at your local sporting goods mega-store. A high quality barbell is worth every penny and will last a lifetime. (Note: A smith machine doesn't count.)
2. A Full Squat Rack
The squat rack is the foundation of a serious home gym. A decently constructed squat rack will last forever and ensure your safety when lifting alone. The J-hooks and safety pins in a squat rack are adjustable to accommodate any barbell exercise where the bar doesn't start and end on the floor. First, you set the J-hooks to hold the bar in the correct starting position then set the pins just below the bottom of the barbell path. While inside the rack, if you fail to complete the rep and cannot get the bar back onto the J-hooks, just lower the bar back down and the safety pins will catch it, preventing you from being stapled to the floor or having your throat crushed under the weight. The rack should have four upright post and safety pins that attach at two points so it will be impossible to miss them. Most racks even have pull ups handles, which is a nice bonus. Here's a quick video of my friend Andre using my squat rack.
.3. Iron plates
The barbell needs to be loaded with weights, and this is where you can try to save a little money. Shop around town for the best price. Buying locally is probably going to be better than paying the freight from an online store. Most importantly, make sure they are round, I cannot stress this enough. Whoever thought the hexagonal or octagonal iron plates were a good idea has never completed a single rep of the deadlift. The odd shape cause them to shift around when the bar hits the floor.
The sporting goods mega stores might be a good place to looks for plates. They usually run sales on starter sets with a basic breakdown of 2.5lb, 5lbs, 10lb, 25lb and 45lb pairs. Again, try to avoid the barbell that comes with these packages. Also, try looking at craigslist or a local used sporting good shop for a good deal on iron plates. Like the squat rack and the barbell, iron plates will last a lifetime or more. After you can deadlift the entire starter set, then you only need to buy more pairs of 45s. Hopefully, a lot more pairs.
4. A Flat Bench
The bench press is the only barbell lift done while laying down with the bar positioned directly over your major organs and airways. This bar position makes the bench press the most dangerous lift you can perform in the gym. To safely preform the bench press at home with a barbell you need a quality bench and a full squat rack. If you do not have a full squat rack, then you should never bench press alone. The bench should be around 3 feet long, between 16 and 18 inches high, and about 12 inches wide. I use the Rogue Flat Utility 2.0 bench purchased online for about $200. In this video you can see how I setup my squat rack for bench pressing.
5. A Big Rubber Mat or Wooden Platform
The squat has been called the king of all exercises, well if that's true, then the deadlift is the five-star general. In my opinion, you should be doing both. The deadlift is the simplest exercise regarding equipment. All you need is a bar and some iron plates. The deadlift starts and ends with the loaded bar sitting on the floor. That's where the rubber mat or platform comes into play, to protect the floor and provide a non-slip surface for your feet. Our local farm supply store sells big rubber mats for horse stalls that are perfect for quick deadlift platform. In my gym, I took four pieces of plywood and glued them together to make a solid 8' x 8' wood slab. Then covered that with a very dense commercial carpet. (Note: make sure you set your home gym up on a stable floor. A concrete basement or garage floor is great. An upstairs bedroom, not so much.)
Bonus item: A Training Program
With these 5 pieces of equipment and a good training program, you can make huge strength gains right at home. For people who are just starting their fitness journey, I recommend reading Starting Strength: Basic Barbell Training, 3rd edition by Mark Rippetoe. This book will teach you the proper way to lift a barbell and how to progress from a beginner to an intermediate level. For more advanced lifters who are looking for a program, I recommend 5/3/1: The Simplest and Most Effective Training System for Raw Strength (2nd Edition) by Jim Wendler. 5/3/1 requires a fair amount of planning and math, so to make that part extremely simple, I developed this spreadsheet that calculates, tracks, and analyzes everything. Check it out here.
Want to see more of my home gym in action? Check out more of my training videos on Instagram!