The number of home espresso machines on the market today is truly mind-blowing. There are many brands to choose from, and within each brand there are often several models. The price range goes from a few thousand rand to over R100,000.

It's important to understand the fundamentals of making espresso before you buy a machine. Making espresso is a combination of art and precise science — it takes good equipment, effort, and dedication to make an excellent cup.

What actually makes a good espresso?

Espresso is made by pushing water at an exact temperature, under very high and consistent pressure, through a bed of finely ground coffee at a precise dose, for a fixed period of time. The resulting espresso must be the exact correct quantity every time. Your machine needs to deliver water at a consistent, correct temperature and pressure for you to make a good espresso.

Why do I need a good grinder, not just a good machine?

One of the most important elements of a good espresso is coffee ground to the correct fineness — and every type of bean (variety, blend, and roast profile) has a different ideal grind size. This means a good quality grinder is essential.

You are wasting your money if you buy an espresso machine without also buying a good quality grinder. You will never get the best out of your machine or your coffee using pre-ground coffee or a low quality grinder. In fact, getting a good grinder is more important than the espresso machine itself — a good grinder paired with an average machine can still make a reasonable shot, but the most expensive machine paired with a bad grinder will never make a decent espresso.

What water temperature and pressure does a good espresso machine need?

Brewing water should be delivered at a consistent temperature in the 92-98°C range — the more expensive machines often have a PID(Electronic temperature control). This results in more consistent water temperature. You also need good-tasting, good-quality filtered water.

The pump delivering water to the group head should be capable of around 15 bar, though the ideal brewing pressure is in the 9–10 bar range. Entry-level to mid-range machines typically use vibrating (noisier) pumps, while more expensive machines use rotary pumps, similar to commercial equipment.

What should I look for in a portafilter and group head?

A good portafilter is typically made from chromed brass or stainless steel, around 58mm in diameter, and weighs about 600g — the material and weight matter for thermal stability. The portafilter basket should be stainless steel and hold a minimum of 14g of coffee.

The group head should be made of brass, again for thermal stability.

What's the difference between boiler configurations?

The boiler configuration is a major consideration. A double boiler with PID is the best option and by far the most expensive. Good quality entry level machines like the Rancilio Silvia or Gaggia Classic have a single boiler that can be retrofitted with a PID.  A thermoblock machine is the least desirable but most affordable option.

Should I choose a machine with a water tank or a plumbed-in version?

A plumbed-in machine is great if it will always stay close to a water connection. A water tank is more convenient if you'll be moving the machine around, or if there's no water connection nearby. Not all machines are available with a water connection so check carefully if this is something that is important to you.

How much should I budget for a home espresso machine?

Stretch your budget as far as you reasonably can without getting into financial trouble — generally, the more you spend, the better the equipment. It's better to save for a higher quality machine than to buy a low quality one. You should never buy an espresso machine that works without a pump. Really cheap machines use steam pressure rather than a pump. These machines can normally be identified by a screw-on cap on the water reservoir which doubles as a boiler.

As covered above, make sure your budget includes a good quality grinder — this matters more than the machine itself.

What else should I consider before buying?

Understand the pros and cons of the different boiler configurations, and make sure you can genuinely live with the downsides of whichever one fits your budget. If a compromise (for example, a single boiler) feels unbearable, don't buy it — rather wait and save for the one that will actually work for you. You'll likely always make some compromise to fit a budget, but make sure it's one you can live with.

Also consider the physical space where the machine will live:

• How is the water tank refilled? If it refills from the top, a cupboard directly above the machine may mean moving the machine every time you refill it.
• Some machines are quite heavy.
• Factor in your grinder's height too — will it fit under your cupboard, and is there space to load new beans without pulling it out each time?