• double-glazed window frame cross-section showing materials and construction on a white background
  • Double-glazed window frame with wooden sill and black trim on a white background
  • Double-glazed window frame with wooden sill and black trim on a white background
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Outward Opening Timber Window (P11T)

Outward Opening Timber Window (P11T)

FRAME

If you are looking for a traditional timber casement or cottage window design, Norrsken’s P11T Outward Opening Timber Window is perfect. The all-timber construction of the windows makes it suitable where conservation or planning requirements stipulate timber. 

This double-glazed outward opening window delivers very good performance - above average for a double-glazed window.

The application of technically advanced sprayed coatings (in a full range of RAL colours) gives enhanced durability and a superb finish.

The double-glazed unit is a 24 mm unit with argon gas filling, warm edge spacer bar and an internal pane of Low-E glass. Whole window U-Values are around 1.2 W/m²K. 

The frame is available in two depths 116 mm (+ 12.5 mm for aluminium cladding) and 92 mm. On the deeper section frame a decorative moulding finish is available.

 

  • Thermal Performance: U-Value 1.24
  • Sound Performance: 33db
  • Security Performance: PAS 24 Certified

Technical Information

Opening types Fixed pane, Top hung, Side hung, Fully reversible
Frame depth 89/116 mm
Whole window U-value 1.24 W/m²K
Glass U-value 1.12 W/m²K
Glass package 24 mm double glazed, one pane Low-E, argon filled
Sound insulation 33 db
Air permeability Class 4 (EN 12207:2000)
Watertightness Class E1200 (EN 12208:2001)
Wind load Class 5C (EN 12210:2001)
Timber Colours RAL
Aluminium Colours RAL, IGP textured

Data Sheet

p11t.pdf

Drawing

p11t.dwg

View full details

Which windows are right for you?

Take our short survey to discover the perfect windows for your project.

Create Something Distinct

Every Norrsken order is unique. Beyond custom dimensions and precision manufacturing, we provide the design flexibility to perfectly express your vision.

From custom shapes and specialized hardware to powder-coated trims and distinct hardware - find the finishes you need, whatever your project specification.

OPTIONS

Colours & Finishes

Complete design freedom to perfectly match your architectural vision.

Choose from solid colours or natural finishes with dual-colour options available on virtually every product – select one colour externally and another internally using any RAL specification.

Handles & Hardware

Our curated hardware selection combines exceptional functionality with aesthetic flexibility.

While some components are product-specific for optimal performance, we offer extensive customization across styles, colors, and finishes.

Glass Options

Advanced glazing solutions engineered for optimal comfort and performance.

Our comprehensive glass selection provides complete flexibility including double and triple glazing, solar control, and obscure options. Glass delivers the highest insulation performance in any window - with proper specification, you can maximize beneficial solar gain while preventing overheating.

Modern building with triple-glazed window, a balcony overlooking a cloudy sky and water.

Marine Finish

Marine-grade finishing for projects within 1,500 meters of the sea, ensuring exceptional durability in challenging coastal environments.
Close-up of a building exterior with wooden slat wall and triple-glazed window.

Sills & Trims

Bespoke sills and precision trims for unique architectural features. Specialized solutions including steel beam coverings and complex junction details.

Opening Options

Outward opening windows were originally developed for harsh climate conditions in Northern Europe and are the dominant type in the UK, Ireland and Scandinavia.

As these countries experience more challenging weather than many other European countries, the outward opening window works well because strong winds tend to force it to close more tightly, improving its weather resistance. Outward opening windows can be: top hung, side hung or fully reversible. Triangular, circular and semicircular fixed windows are also available.

TOP HUNG

SIDE HUNG

FULLY REVERSIBLE

Modern room with large triple-glazed windows offering a view of a field, featuring a cozy corner with a chair and blanket.

TOP HUNG

Perfect for high-level ventilation and privacy, top hung windows open outward from the bottom with built-in friction brakes.

Ideal for bathrooms and kitchens where you want fresh air with privacy, as cool air flows in below while warm air escapes above. The design maintains excellent thermal performance and energy efficiency through advanced sealing systems.

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SIDE HUNG

Our versatile side hung windows open outward on side hinges, offering maximum opening area and excellent ventilation without taking up internal space.

The classic choice for most residential applications, providing excellent ventilation control and unobstructed views. Multi-point locking systems ensure security while maintaining the sleek aesthetics that complement both traditional and contemporary homes.

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FULLY REVERSIBLE

Clean your windows safely from inside with fully reversible operation, rotating 180 degrees for complete access to both sides of the glazing.

Particularly valuable for upper floors and hard-to-reach locations, these windows rotate completely, eliminating the need for external cleaning access. They feature weatherproof sealing and varied ventilation options as users can control airflow from multiple angles.

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Unmistakably trusted.

The highest compliment is a recommendation. These are the voices of those who placed their trust in us.

"Excellent Company from start to finish… If only every window supplier operated like this! I have used many others over the years on various projects but Norrsken far exceeded all of them… I hope this helps you make a decision for what is probably a large chunk of your budget… They are totally worth it"

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Angela Smith

Self Builder

“Having used Norrsken in the past we were happy to recommend them to one of our clients who was looking for the best sound proofing and weatherproofing they could get being set on a hill top overlooking the sea and facing strong westerly winds. They were not disappointed. A quality product, delivered well and on time. Thankyou.”

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Ken Pearson

Homeowner

"Fantastic professional service, from the original design to the final installation. The triple-glazed windows and doors that have been fitted to our new house are of a very high quality and look amazing. We definitely made the right choice when we decided to use Norrsken, nothing is too much trouble for them."

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Nigel

Homeowner

"I did my research before contacting Norrsken but they had come highly recommended by our Architect for our Passive House self build.

From the first meeting with Nick we felt confident that they were the Company for us."

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Ali and Brian Manning

Passive House Self Builders

“The quality of the triple glazed, alu-clad windows and doors is superb. They feel so reassuringly solid ... I opted for a wood stain for the internal finish on the frames, and am so glad I did, as it shows off the beauty of the wood perfectly. The whole process from order to installation went smoothly. I thoroughly recommend Norrsken.”

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Gareth

Homeowner

"Norrsken provided attentive service from drawings to on-site installation for our project at National Trust Stourhead and we would definitely recommend and repeat commission them on future projects."

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Charlotte Hill-Baldwin

Architect, H-B Designs

“From our very first interaction to the aftercare support, Norrsken has been exceptional. The quality of their windows is outstanding - beautifully designed, expertly crafted, and a real standout feature in our home. They've truly elevated the overall look and feel of the house.”

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Neil Southwell

Self Builder Homeowner

“I can highly recommend Norrsken… After much research I found that Norrsken could beat all of the quotes for a high quality triple glazed option. The windows are beautifully crafted and have received lots of positive comments….  I found the whole team at Norrsken incredibly friendly and helpful…”

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Douglas Munro

Selfbuilder

Designed to deliver

From materials to management, every detail matters to us.
Creating homes that are warmer, quieter more efficient for decades to come.

Ready to get started? Call the team now on 01202 632777

Front elevation view of double-glazed features in a coastline renovation.

Passive House Standards

Engineered to meet or exceed Passive House benchmarks. Norrsken products support low-energy builds without compromising design.

Superior Thermal Efficiency

Exceptional insulation performance that transforms how your home feels, delivering year-round comfort while dramatically reducing energy consumption.

Full Range of Finishes

Design freedom to match your architectural style. Comprehensive color and finish options bring your exact vision to life.

Full Range of Materials

Premium timber and alu-clad options engineered for decades of performance and the aesthetic character your project demands.

Planning & Support

Expert guidance from concept to completion that transforms complex projects into seamless reality without compromise.

On-Site Project Management

We oversee every detail from delivery to final handover, ensuring seamless installation coordination that protects your timescales.