Door Knobs – Essential Guide to Materials, Sizes & Styles

Choosing the right door knob is a small decision that can affect the look, security, and function of every room in your home. With styles ranging from antique brass to minimalist stainless steel, and materials that demand different levels of care, the options can feel overwhelming. This guide breaks down the essential factors—size, material, style, and location—to help you select the perfect knob for every door.

Whether you are updating a single wardrobe, renovating a period property, or fitting out a new build, understanding the basics of backset, borehole, and finish will save you time and prevent costly mistakes. We cover internal and external requirements, installation tips, and the key standards that apply in the UK.

What are the best door knobs for internal doors?

Insights for internal doors

For internal doors, style and ease of use are usually the top priorities. Most internal door knobs are non-locking and purely decorative or functional. Brass remains the most popular material for period homes due to its patina and strength, though ceramic and glass options are frequently chosen for bathrooms and wardrobes for their aesthetic appeal. It is worth noting that ceramic and glass can be more fragile than metal.

• Brass remains the most popular material for period homes due to its patina and strength.
• Ceramic and glass knobs are often used in bathrooms and wardrobes for aesthetic appeal but can be fragile.
• Internal door knobs are not designed for outdoor use – they lack corrosion resistance and locking mechanisms according to building regulations.
• Many suppliers offer knobs on a rose or backplate; the distance between screw centres is typically 57mm or 65mm for UK doors.
• Door levers are sometimes preferred over knobs for ease of use, especially in high-traffic areas or for accessible design.
• Dummy knobs are a non-locking, decorative-only option suitable for French doors or closet doors.

Which material is best for door knobs: brass, chrome, or glass?

The best material depends on where the knob will be used and the desired aesthetic. For exterior doors, weather resistance and security are critical. Stainless steel is highly durable and won’t rust, making it ideal for exterior and humid environments. Solid brass, while attractive, requires an outdoor-rated finish for exterior use to avoid tarnishing, as noted by hardware specialists. Cast iron is known for its durability and classic look, while zinc alloy is a reliable, cost-effective option for general hardware.

Brass for classic durability

Solid brass offers a timeless look that works with both traditional and contemporary designs. As Willow & Stone Co., a period hardware specialist, notes, solid brass patinas beautifully over time, and an unlacquered finish can provide an authentic aged look for period homes. However, many knobs sold as ‘brass’ are actually brass-plated over zinc or steel, so checking for ‘solid brass’ is important for longevity.

Chrome for modern style

Polished chrome has a sleek, reflective finish that suits modern interiors. Satin chrome offers a softer texture. A trade-off is that chrome can show fingerprints and water spots, which might require more frequent cleaning in high-touch areas.

Glass for elegance

Glass knobs are non-porous and easy to clean, making them a viable option for bathrooms. However, glass can be slippery when wet, and coloured glass may fade in direct sunlight. For cupboards and wardrobes, wood offers rustic appeal but lacks the durability of metal for high-use doors.

Wood, glass, porcelain, and leather offer distinct textures and visual interest but may require extra care and lack the durability of metal. For high-traffic internal doors, metal knobs are almost always the more practical choice.

How to measure and choose the correct door knob size?

Proper measurement is the most critical and often overlooked step in buying a door knob. As DIY Doctor, an expert trade site, advises, “Always measure the distance between the screw centres before ordering a new door knob – it’s the most common mistake.” Before purchasing, measure three key dimensions: door thickness, backset, and borehole diameter.

The standard door thickness for interior doors is 1 3/8 inches, while exterior doors are typically 1 3/4 inches. Many manufacturers offer adapters for doors up to 2 ¼ inches thick. The backset—measured from the centre of the borehole to the edge of the door—is usually 2 3/8 inches or 2 3/4 inches. Some doors have a 5-inch backset, which requires special latches. The borehole diameter is a standard 2 1/8 inches, though older doors may have smaller holes that can be widened.

Understanding backplate and rose dimensions

Door knobs come either on a backplate (a long plate) or on a rose (a circular base). The distance between screw centres is a critical measurement, typically 57mm or 65mm for UK doors. The spindle size—the square rod connecting the knobs—must also match your door thickness. For multi-point locking systems found on uPVC or composite doors, you will need to measure the PZ distance (handle centre to keyhole centre), which is often 92mm.

Determining door handing

For external doors with locks, you must determine the door’s handing. This involves checking if the door is left-hand (hinges on the left when standing outside) or right-hand. This will ensure the lock mechanism functions correctly.

How to match door knobs with your existing door furniture?

Matching the knob style to the era of your home creates a cohesive look. For Art Deco or Victorian decor, antique-style knobs with an aged look can add a vintage touch. For historic homes, replicating the original style is key to preserving character. Solid brass knobs with oval roses were common in Georgian homes, while ornate brass, glass, and ceramic with patterned backplates defined the Victorian era.

It is also important to differentiate between a door knob and a door handle (or lever). A door knob is a round or shaped grip that you turn, while a lever is a horizontal bar that you push down. Levers are often required in public or accessible buildings for ease of use, but for private homes or cupboards, knobs can be perfectly functional and offer a wider range of decorative styles.

How did door knob styles evolve in the UK?

Understanding the history of door knob styles can help you make an authentic choice for your property.

1. Georgian (1714–1830): Brass round knobs often with oval roses; simple and elegant in design.
2. Victorian (1837–1901): Ornate brass, glass and ceramic knobs; highly patterned backplates were common.
3. Art Deco (1920s–1930s): Geometric shapes, chrome finishes, glass details, and stepped forms defined this era.
4. Mid-century (1950s–1970s): Minimalist metal knobs, wood handles, and bakelite were typical of the period.
5. Contemporary (2000s–present): Stainless steel, satin chrome, and smart knobs with keyless entry systems are now standard.

Myths, facts, and the importance of measuring twice

A clear understanding of the facts can prevent common mistakes. Here is a breakdown of established information versus common misconceptions.

Why does door knob choice matter beyond aesthetics?

The choice of a door knob has implications for security, accessibility, and long-term maintenance. For external doors, knobs with integral locks must meet UK building regulations. It is important to look for knobs tested to PAS 24 or an equivalent standard. Simple internal knobs offer no security and should never be used on an external door.

Accessibility is another factor. While lever handles are often preferred for ease of use on main doors, knobs can be easier for those with limited dexterity to grip when used on cupboards and wardrobes. Environmental factors also play a role. Homes in coastal areas require corrosion-resistant materials like stainless steel or anodised brass to prevent damage from salt air. Regular waxing with a quality furniture wax can help preserve unlacquered brass.

What do the standards and experts say about door knobs?

“Specifies performance requirements for door handles, including knobs, used on hinged doors.”

– British Standards Institution (BS 4951:2000), reference for security and durability standards.

“Always measure the distance between the screw centres before ordering a new door knob – it’s the most common mistake.”

– DIY Doctor, practical advice for DIY installers.

“Solid brass patinas beautifully over time – consider an unlacquered finish if you want an authentic aged look.”

– Willow & Stone Co., period hardware specialist, offering material advice for period homes.

What should you do next with your door hardware project?

Selecting the right door knob comes down to matching the material, size, and style to the specific door and its location. Start by measuring your door’s thickness and backset, then choose a finish that suits your home’s character and your practical needs. For readers looking at a broader home project, the Kitchen Cabinet Guide 2025 – Best Brands and Costs in the UK may offer useful parallel information on choosing fixtures and fittings.

Frequently asked questions