SDS vs Combi Drill: Which Do You Need for Masonry?

Quick Comparison: SDS vs Combi Drill

What Is a Combi Drill?

A combi drill is the standard 18V drill most UK homes already own. The version UK retailers call a combi drill combines three functions in one body: plain drilling for wood and metal, hammer drilling for light masonry, and screwdriving with an adjustable torque clutch. You twist the collar to the drill icon for holes, the hammer icon for brick, or a number for screw torque. The 13mm keyless chuck grips any round-shank bit, which means your existing drill bits, hole saws and driver bits all fit without adaptors. That versatility is the reason a combi drill is almost always the first power tool people buy.

The hammer action in a combi drill is mechanical and fairly light. Two ridged plates inside the gearbox ride over each other as the chuck spins, making the bit judder forward by about a millimetre at up to 30,000 bumps per minute. It is enough to crumble soft London brick or aerated block, but it relies on you leaning your weight into the tool. On hard Staffordshire engineering brick, dense concrete lintels, or old stone, progress slows to a crawl and the bit overheats. Noise is high, dust is high, and the bit can wander if you do not keep the drill dead square. For the odd 6mm wall-plug hole this is fine - for a row of 10mm anchor holes it is hard work.

If your budget only stretches to one drill, a brushless combi is still the right first buy. Models like the DeWalt DCD778S2T 18V XR Brushless Hammer Drill at around £179 as a kit with two batteries and a case, or the Bosch Professional GSB 18V-55 as a lighter body-only option, cover 90% of DIY tasks. The Makita DHP486Z 18V LXT Brushless is another proven choice in the same class. Just do not expect any of them to behave like an SDS when the wall is concrete. That is not a fault - it is a different mechanism entirely, and understanding that saves you burning out bits and patience.

What Is an SDS Drill?

SDS stands for Slotted Drive System (originally Steck-Dreh-Sitz). An SDS rotary hammer looks like a bulkier drill, but inside it works like a small electro-pneumatic jackhammer. A piston driven by the motor compresses air and fires the bit forward with real impact energy, typically 1.5 to 2.6 joules for 18V models, while the bit still rotates to clear dust. The bit shank has grooves that slide in the SDS chuck, so the bit can hammer forward independently of the chuck body. That is the key difference: a combi drill vibrates the whole chuck, an SDS fires only the bit. The result is far higher impact energy with less effort from you, less noise transferred into the handle, and much faster progress in hard materials.

Because the chuck is SDS-Plus, you need SDS-Plus bits - standard round bits will not lock in. The good news is Bosch 6-piece SDS Plus sets are inexpensive and widely available, and you can add an SDS-to-keyless adaptor if you want to use normal bits with the hammer disabled. Most SDS hammers also offer rotary-only mode for wood or metal and, crucially, hammer-only mode where the rotation stops and the tool becomes a chisel for tile removal or chasing. No combi drill can do that.

For UK housing - concrete lintels over windows, hard facing bricks, stone walls in period properties, and garage floors - the difference is night and day. Where a combi drill might take two minutes and a lot of pressure to get a 10mm hole 60mm deep, an SDS does it in 15 seconds with the weight of the tool doing the work. If you have ever searched how to drill into brick or how to drill into concrete without a hammer drill, the honest answer is often that you should not - you should use the right hammer action instead.

Head to Head: The Jobs That Decide It

The spec table tells you how they work. The jobs below tell you what to buy, because most people choose after a specific task forces the issue.

Hanging shelves and wall plugs (5-8mm in brick or block)

This is where a combi drill just about copes. If your walls are soft red brick or aerated Thermalite block, a sharp masonry bit and a combi on hammer will sink a 6x40mm plug hole in under 30 seconds. For this alone you do not need an SDS. If the wall is hard engineering brick, concrete block, or you need 8mm holes for heavier fixings like shelf brackets that actually stay up, the combi starts to labour and the SDS pulls ahead quickly. Rule of thumb: if you are doing more than six plug holes in a hard wall, you will wish you had borrowed or bought an SDS.

Concrete lintels, stone and hard brick (8-16mm)

Lintels over windows and doors in UK houses are often pre-stressed concrete. A combi drill on hammer will mark the surface and make a lot of noise without advancing. An SDS with a 10mm bit goes through the same lintel in seconds because the piston delivers joules, not just vibration. The same applies to Yorkshire stone, Cotswold stone, and Class B engineering bricks. If your SDS rotary hammer shortlist includes the Bosch GBH above, this is exactly the job it was bought for, and it is the reason tradespeople do not attempt lintels with a combi.

Core holes and larger diameters (20-68mm)

Bathroom extractor fans, tumble dryer vents, and cable entries need core bits that a combi drill cannot safely drive. An SDS rotary hammer with a core kit and the hammer disabled for the initial cut will handle a 52mm or 68mm core through a single-skin brick wall. With a combi you risk stalling, wrist twist, and burned-out motors. If you plan even one core hole, the SDS pays for itself versus hiring one for a weekend.

Chiselling, tile removal and chasing

Only an SDS offers hammer-only mode. You fit a chisel bit, set the selector to hammer only, and the tool chips tiles, removes render, or chases a channel for cable. A combi drill has no equivalent. For kitchen refits or removing old tiles, this single mode can justify owning an SDS even if you already have a good combi.

Weight, noise and everyday convenience

A combi drill wins on handling. At around 1.7kg ready to go, you can use it overhead to put up a curtain rail without your arms aching. An SDS at 2.7kg plus battery is noticeably heavier and bulkier in a tight understairs cupboard. It is also louder in hammer mode, though it finishes the hole faster so total noise time is shorter. If you only drill timber and occasional soft brick, carrying the extra weight makes no sense. If masonry is regular, the weight is the price of progress.

Which Should You Buy?

Buy a combi drill first if you do not yet own a decent 18V drill. It drills wood and metal, drives screws with a proper clutch, and will handle a handful of plug holes in soft to medium brick. The Bosch GSB 18V-55 and Makita DHP486Z are strong body-only choices if you already have batteries on those platforms, and the DeWalt kit above is the best one-box solution.

Buy or add an SDS if you regularly drill concrete, hard brick, or stone, need holes larger than 8mm, need to cut cores, or want chisel mode. In UK housing stock with concrete lintels and dense blockwork, many DIYers buy the combi first and add an SDS within a year once they hit real masonry. Buying the Bosch GBH 18V-26 F as a bare unit keeps cost down if you are already on the Bosch 18V system; otherwise factor in a battery and charger.

Own both if you do serious DIY. The pair covers everything: the combi for everyday drilling and screwdriving, the SDS for masonry and demolition. They use different bits anyway, so you are not duplicating - keep a set of standard masonry bits for the combi for the odd soft-brick hole and a set of SDS-Plus bits like the Bosch 6-piece SDS Plus set for the SDS. That is the setup most UK tradespeople carry, scaled down for home use.

One last buying tip: do not use an SDS-to-keyless adaptor with hammer enabled to drill masonry - the adaptor is not designed for hammer loads and you lose the SDS impact advantage. Use it only in rotary mode for wood or metal when you want to avoid swapping the whole chuck. For masonry, always use the proper SDS bit in the SDS chuck.

Frequently Asked Questions

Final Verdict

For most UK DIY, the combi drill remains the workhorse - it builds furniture, hangs pictures, and deals with the easy brick. The SDS rotary hammer is the specialist that earns its keep the moment you meet real masonry. If your house is post-war concrete, engineering brick, or stone, and you plan more than the occasional plug hole, adding an SDS like the Bosch GBH 18V-26 F alongside your combi will save you hours, bits, and frustration. Start with the combi if you own nothing, add the SDS when masonry becomes regular - that order wastes the least money and covers every job on the list.