Is Residence 9 worth the extra cost?

If you live in a conservation area or a period property, yes. The 100mm depth is often mandatory for planning. For modern homes, R7 offers the same external look for less.

Can I have triple glazing with Residence windows?

Yes. Both Residence 7 and Residence 9 accommodate 44mm triple glazing, achieving U-values as low as 0.8 W/m²K.

What is a mechanical joint or Timberweld?

A Timberweld joint mimics traditional wood construction with straight 90-degree lines, replacing the standard 45-degree diagonal uPVC weld.

Timber - PVC - Aluminium - Windows, Doors & Conservatories in Hampshire

Residence 7 vs Residence 9: The Complete Comparison Guide

Start Reading Get a Quote

Residence 7 vs Residence 9: The Complete Comparison Guide

📌 The 20-Second Summary: R7 vs R9

Why are Residence 7 windows different to Residence 9? The primary difference lies in the frame depth and the internal decorative profile; Residence 9 replicates traditional 100mm timber frames with decorative interiors, while Residence 7 offers a 75mm depth with modern flush aesthetics.

External Looks: Both systems are identical from the street, featuring the premium “flush sash” design favoured in Hampshire.
The Verdict: R9 is for Article 4 heritage properties; R7 is the ideal choice for modern homes due to easier installation.

When choosing between the Residence 7 and Residence 9 window systems, the decision is rarely just about “looks”—it is about architecture. While both systems offer market-leading energy efficiency and a beautiful flush exterior, they solve different problems.

R9 was built to satisfy strict planning officers in heritage zones like Winchester and Andover. R7 was built to bring that heritage look to modern homes without the installation headaches often found when fitting 100mm frames into standard UK apertures.

1. The Frame Depth Difference: 75mm vs 100mm

This technical difference dictates how the window fits your home and whether internal remedial work is required to accommodate the frame.

📏 Residence 9 (100mm)

The Heritage Standard. Old 19th-century timber windows were often 100mm thick. To replicate this, R9 uses a 100mm deep frame. Warning: Installing this in a modern aperture often requires cutting back internal plaster or timber sills to make it fit.

🔨 Residence 7 (75mm)

The Modern Standard. R7 was engineered to match standard UK window depths (typically 70mm). At 75mm, it slots easily into existing apertures with minimal disruption to your plaster line.

For detailed guidance on planning constraints, we recommend visiting the UK Planning Portal.

2. Internal Aesthetics: Flush vs Decorative

From the kerbside, both windows look identical. The choice below is entirely about the view from inside your room.

Residence 9 (Decorative)

Mimics intricate Victorian joinery with a “Staff Bead” sculptured profile inside.

R9: Decorative Staff Bead profile

Residence 7 (Flush)

Features a clean, “Square Bead” flush interior for contemporary, minimalist lines.

R7: Modern Square Flush profile

3. Technical Specification Comparison

Feature	Residence 7 (R7)	Residence 9 (R9)
Frame Depth	75mm (Modern)	100mm (Heritage)
Thermal Chambers	7 Chambers	9 Chambers
Internal Bead	Square / Flush	Decorative / Staff
Joint Type	Timberweld®	Timberweld®

4. Construction: Timberweld® Technology

KJM Group standardises on Timberweld® technology for both systems. This creates a mechanical 90-degree “Butt Joint” that looks exactly like wood construction inside and out, but with the strength of a modern weld.

Authentic Timberweld® butt joint detail.

5. Heritage Hardware

A heritage window is only as authentic as its handle. We finish our Residence installations with genuine heritage ironmongery, available in Monkey Tail and Pear Drop styles.

Monkey Tail handles in Pewter Patina add the final touch.

6. Frequently Asked Questions

If you live in a conservation area or a genuine period property, yes. The 100mm frame depth and decorative internal detailing are often mandatory to satisfy local planning officers. For modern homes, R7 offers the same external look at a lower price point.

Yes. Both Residence 7 and Residence 9 accommodate 28mm double glazing or 44mm triple glazing. With triple glazing, both can achieve U-values as low as 0.8 W/m²K (Passivhaus standard).

A standard uPVC weld fuses plastic at 45 degrees, leaving a diagonal line. A mechanical joint (or Timberweld) mimics how wood is joined—straight 90-degree lines where the horizontal and vertical bars meet.

📚 Explore the Residence Knowledge Hub

🏆

R7 Specs

Technical data sheet

🏛️

R9 Specs

Heritage performance data

📜

Planning Guide

Conservation Area info

💰

Cost Analysis

Price comparison guide

About
Latest Posts

Mark Pearce

With over four decades in the glazing industry, Mark Pearce has been at the heart of KJM Windows & Conservatories since 1983. Starting as a building labourer, he quickly rose through the ranks, working as a window and door installer from 1984, a factory operator manufacturing windows later that year, factory manager in 1992, and joining the sales team in 1994. Becoming a Director in 2002, and finally, the sole owner in 2010, Mark Pearce is truly a double glazing expert and has led KJM to become a leading supplier of high-quality windows, doors, and conservatories across Andover and the South of England.

Mark Pearce is a highly experienced specialist in the double glazing industry, having built his knowledge from the ground up through hands-on experience in installation, manufacturing, sales, and business management. Beyond his role at KJM, Mark is a keen blogger, writer, and traveller, often sharing insights on the latest innovations in the home improvement industry.