Sash Horns for Timber Sash Windows

Sash Window Horns

Sash horns are the small shaped extensions at the ends of a sash window’s meeting rail. They were introduced to strengthen traditional timber joints and to stop the sashes from being pushed up too far. Today they’re also used to match period details on many London and Home Counties homes, especially in conservation areas.

What Are Sash Horns?

A sash horn is a visible projection that often extends below the meeting rail of a timber sash window. Originally introduced during the Victorian era, horns were added to strengthen the mortise and tenon joints of the sashes and prevent the window from being opened too far. Over time, they became a signature detail in period architecture.

Key Takeaway

Historically used to reinforce the lower sash corners on larger windows.
Common in London terraces and conservation streets.
Profiles can be selected from our standard set of 12 options shown below.

How to choose the right horn

Match the street: Look at neighbouring originals; choose a similar length/shape.
Check planning notes: In conservation areas, planners often expect horns where they existed before.

Why Sash Horns Matter Today

While originally structural, sash horns continue to play a role in maintaining the correct proportions of traditional timber windows. They help meet conservation area standards and can give a more authentic profile, especially when matching historic properties.

Sash Horns and Restrictors

When fitting sash restrictors, it’s important to note that they sit 100mm above the sash horn. If a restrictor is accidentally left engaged, the sash can catch against the horn, which may cause damage to the paint or timber. For this reason, we don’t include sash horns on the inside of the bottom sash as standard. If you would like them added, this can be arranged on request.

Learn more about sash restrictors here.

Explore Our Sash Horn Styles

We offer 12 sash horn styles that suit a variety of period homes and traditional sash window designs. These horns are optional, but many customers choose to include them when matching existing windows or following conservation guidelines. If you’re not sure which one is right for your project, your installer or architect may be able to advise.

When selected, sash horns are fitted as standard on the exterior of the top sash only. If you’d also like horns on the interior bottom sash, just let us know — we include this at no extra charge.

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FAQs:

Have a question about delivery or storage? These are the queries we’re asked most often. If you don’t see what you need, just get in touch and we’ll be happy to help.

Do I have to include sash horns?

Not always. If your street or building originally had plain sashes, “no horns” can be specified. In conservation areas, planners often expect horns to be replicated.

Are horns structural?

They add stiffness at the corner of the sash and help resist racking on larger windows.

Will horns affect fire‑egress?

No. Egress is governed by clear opening size and hardware choice, not the presence of horns.

Can you copy my existing horn shape?

Yes, we can have a look at this for you. Send a clear photo of the lower sash corner and we’ll advise the best match or create a custom variant.

Do horns add cost or lead time?

Standard horns are included in our pricing; custom shapes may require a small surcharge and extra time.

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