• triple-glazed window frame cross-section showing materials and construction on a white background
  • triple-glazed window frame showing wooden and metal components on a white background
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Inward Opening Timber Window (P33T)

Inward Opening Timber Window (P33T)

FRAME

Where a full timber window is preferred, this triple-glazed inward opening window delivers superb performance and is suitable for highly energy efficient homes including Passive houses. 

The 88mm laminated timber frame and deeper glazing unit give improved performance over the P23 window.

Tilt and turn windows can be tilted in for ventilation and open inwards for access and cleaning.

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

The triple-glazed unit is a 50 mm unit with argon gas filling, warm edge spacer bar  and two internal panes of Low-E glass. Whole window U-Values are around 0.7 W/m²K. 

This window is available with a Juliet Balcony.

 

  • Thermal Performance: U-Value 0.74
  • Sound Performance: 35db
  • Security Performance: PAS 24 Certified

Technical Information

Opening types Fixed pane, Tilt and turn, Tilt only, Turn only
Frame depth 88 mm
Whole window U-value 0.74 W/m²K
Glass U-value 0.48 W/m²K
Glass package 50 mm triple glazed, two panes Low-E, argon filled
Sound insulation 35 db
Air permeability Class 4 (EN 12207:2000)
Watertightness Class E1050 (EN 12208:2001)
Wind load Class C4 (EN 12210:2001)
Timber Colours RAL
Aluminium Colours RAL, IGP textured

Data Sheet

p33t.pdf

Drawing

p33t.dwg

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Which windows are right for you?

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

See the P33T in action

At Norrsken, we’re fortunate enough to work on some breath-taking projects.

From barn conversions to innovative new builds, dream homes that take half a decade and an armada of professionals to budget-focused living space renovations and self builds – we’ve seen it all.  

Our windows and doors add beauty and value to homes up and down the country. We work with clients on a vast array of styles, designs, colours, and purposes. That is something we’re quite proud of.  

GALLERY

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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

Popular across Europe, inward opening windows are now growing in popularity in the UK.

With identical build quality and similar thermal performance to outward opening windows, they have three distinct features:

  1. The opening sashes can be opened inwards for easy cleaning
  2. Larger opening sashes are possible with inward opening windows, as the hardware can typically carry more weight
  3. Inward opening products can be configured to include a Juliet Balcony

Inward opening, tilt and turn windows work well for many homes because they can be tilted inwards for ventilation and turned, opening up to 90 degrees internally, making it easy to clean them from the inside. 

TILT-IN

TURN-IN

TILT & TURN

FIXED FRAME

TILT-IN

Tilt-in operation provides secure ventilation by opening inward from the top, creating a controlled airflow while maintaining security and safety.

Ideal for anywhere you want ventilation with security, a gentle inward tilt from the top edge of the window delivers fresh air while the restricted opening prevents accidental falls. The perfect combination of effective airflow, easy operation and energy efficiency.

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Modern house interior with a view of a garden through a triple-glazed glass door.

TURN-IN

The inward opening complement to side hung windows, turn-in windows swing inward on side hinges for full access, ventilation, and easy cleaning.

Opening fully inward from side hinges, these energy-efficient windows provide complete access and maximum airflow with convenient cleaning from inside. Perfect for living spaces where you want the option of wide-open connections to the outdoors.

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triple-glazed window with red floral curtains on a white wall

TILT & TURN

Combining two opening modes in one window, tilt & turn offers gentle top ventilation or full side opening for maximum versatility and control.

The ultimate in window functionality, offering both tilt-in ventilation for secure airflow and full turn-in opening for cleaning and maximum ventilation. Simply turn the handle to switch between modes, giving you complete control over your indoor environment.

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Modern bathroom with a freestanding bathtub, wooden vanity, and large triple-glazed window.

FIXED FRAME

When the view is the star, fixed windows frame it perfectly while flooding your home with natural light and delivering exceptional energy efficiency.

With slim sightlines and minimal maintenance, fixed frame windows also deliver superior thermal performance. Any of our inward or outward opening window profiles can be configured as fixed frames, giving you complete flexibility to match your architectural vision.

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Designed to deliver

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

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

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