If you’re planning an oak framed house, extension, or garden room, one of the most important decisions you’ll make is how to insulate it. The insulation system you choose determines how warm, energy-efficient, and comfortable your building will be for decades to come.
At Sussex Oak Structures, we use Kingspan TEK panels as our preferred insulation system for oak frame buildings. In this guide, we explain exactly what they are, how they work with oak frames, and why they outperform traditional insulation methods.
What Are Kingspan TEK Panels?
Kingspan TEK panels are a type of structural insulated panel (SIPs). In simple terms, they are pre-manufactured building panels that combine structure and insulation into a single component.
Each panel consists of a rigid insulation core — made from polyurethane (PUR) or polyisocyanurate (PIR) — bonded between two sheets of oriented strand board (OSB). The result is a lightweight yet incredibly strong panel that provides both structural rigidity and outstanding thermal insulation in one piece.
Think of it like a high-performance sandwich: two strong outer layers holding a thick insulating filling. Unlike traditional construction where you build a frame and then fill it with insulation afterwards, a SIPs panel does both jobs simultaneously.
Kingspan TEK panels are manufactured in a factory to precise dimensions, meaning they arrive on site ready to be fixed directly to your oak frame. They are available in a range of thicknesses to suit walls, floors, and roof panels.
How Kingspan TEK Panels Work with Oak Frames
Oak frame construction and structural insulated panels are an exceptional pairing. The oak frame provides the primary structural skeleton — the posts, beams, braces, and trusses that give an oak framed building its distinctive character. The Kingspan TEK panels then form the insulated building envelope around the outside of that frame.
This means the beautiful oak frame remains fully visible inside the building. Unlike conventional construction where insulation is hidden between studs, TEK panels sit on the outside face of the oak frame, wrapping the entire structure in a continuous insulated shell.
Wall Panels
For walls, the TEK panels are fixed directly to the outside face of the oak frame, spanning between the oak posts and secured with heavy-duty screws. Because the panels are structural, they don’t require any additional studwork — they form the external wall in a single operation. External finishes such as weatherboarding, render, hanging tiles, or brick slips are applied to the outer face, whilst plasterboard is fixed to the inner face.
Roof Panels
Kingspan TEK roof panels span between the oak purlins or rafters, creating a fully insulated roof without additional rafters, insulation layers, or vapour control membranes. The panels support tile battens and coverings directly. This eliminates the cold bridging that occurs with traditional rafter-and-insulation constructions, as the insulation is continuous across the entire roof plane.
Thermal Performance and U-Values
Thermal performance is measured by U-values — the rate at which heat passes through a building element. Lower is better. Current Building Regulations for new build homes require walls to achieve 0.26 W/m²K or better, and roofs 0.16 W/m²K or better.
Kingspan TEK panels comfortably exceed these requirements:
| Panel Application | Thickness | Typical U-Value (W/m²K) | Building Regs Requirement |
|---|---|---|---|
| Wall Panel | 142mm | 0.21 | 0.26 |
| Wall Panel | 172mm | 0.17 | 0.26 |
| Roof Panel | 142mm | 0.22 | 0.16 |
| Roof Panel | 172mm | 0.17 | 0.16 |
For clients building to Passivhaus or near-Passivhaus standards, thicker configurations can achieve U-values as low as 0.12 W/m²K. Crucially, real-world performance closely matches calculated values because the continuous insulation avoids the thermal bridging that degrades traditional systems in practice.
Advantages Over Traditional Insulation Methods
TEK Panels vs Mineral Wool Between Studs
The traditional approach involved constructing a secondary stud wall outside the oak frame and filling cavities with mineral wool. This method has several drawbacks:
- Thermal bridging: Timber studs make up 15-20% of the wall area and conduct heat three to four times faster than mineral wool, significantly worsening real-world U-values
- Airtightness: Sealing around dozens of studs, noggings, and penetrations is extremely difficult — gaps allow warm air into the insulation, risking condensation
- Speed: Building stud walls, fitting insulation, and taping vapour barriers takes considerably longer than fixing pre-made panels
- Consistency: Mineral wool can slump, compress, or be poorly fitted, leaving gaps that reduce performance
TEK Panels vs PIR Board Between Studs
PIR rigid boards between studs offer better performance than mineral wool but still fall short of SIPs panels:
- Thermal bridging persists: Timber studs still create thermal bridges through the wall
- Gaps are inevitable: PIR must be cut to fit between studs — gaps reduce performance and are sealed inconsistently with expanding foam
- Two-stage process: You must build the stud framework first and then fit insulation — two operations rather than one
- Airtightness: Sealing dozens of individual board edges and junctions is far harder than taping a smaller number of panel joints
The TEK Panel Advantage
Kingspan TEK panels address all of these issues. Continuous insulation eliminates thermal bridging. Factory-made panels deliver consistent thickness with no gaps or compression. Fewer joints make excellent airtightness significantly easier to achieve. The result is a building that performs as well in reality as it does on paper.
The Installation Process
The speed and simplicity of TEK panel installation is one of their most compelling advantages. Here is how the process works on an oak frame project:
1. Design and Manufacture
Once the oak frame design is finalised through our bespoke design service, the TEK panel layout is engineered to match. Panels are manufactured off-site with window and door openings pre-cut, ensuring a perfect fit and minimal waste.
2. Oak Frame Erection
The oak frame is erected first, creating the structural skeleton. The hand-cut joints are assembled and pegged together to form the primary structure.
3. Panel Fixing
TEK panels are lifted into position and fixed to the outside face of the oak frame with long screws. Wall panels fix to the oak posts; roof panels fix to the purlins. A typical house can be fully enclosed within one to two weeks.
4. Sealing and Taping
All panel joints are sealed with expanding foam and airtightness tape to create a continuous building envelope. With far fewer joints than traditional construction, a superior airtight seal is achievable with less effort.
5. Finishes
With the panels sealed, the building is weathertight. External cladding, roofing, windows, and doors are installed. Internally, plasterboard is fixed to the panels directly or over a service void for cables and pipework. Using TEK panels can save two to four weeks compared to traditional insulation methods on a typical oak framed house project.
Cost Comparison: TEK Panels vs Traditional Insulation
Whilst the material cost of Kingspan TEK panels is higher per square metre than mineral wool or PIR boards, the overall project economics tell a different story:
| Cost Factor | TEK Panels | Traditional (Studs + Insulation) |
|---|---|---|
| Material cost per m² | Higher | Lower |
| Additional studwork | None required | Full secondary stud wall |
| Labour time | 1-2 weeks | 3-6 weeks |
| Airtightness work | Simpler and faster | Complex and time-consuming |
| Waste on site | Minimal (pre-cut) | Moderate to high |
| Long-term energy savings | Superior | Good but less consistent |
| Performance gap risk | Very low | Moderate to high |
When you account for the elimination of studwork, reduced labour, faster build programme, and superior energy performance, TEK panels typically represent comparable or better overall value. For many clients, getting weathertight weeks earlier alone justifies the investment by reducing weather delay risk and bringing forward the completion date.
The additional material cost on a typical oak framed extension or house is often offset substantially by savings in labour and programme time.
Environmental and Sustainability Credentials
Kingspan TEK panels align well with the environmental ethos of oak frame construction. Their superior thermal performance means buildings need significantly less energy for heating over their lifetime, directly reducing operational carbon emissions.
Factory manufacture means minimal material waste — panels are cut to precise dimensions off-site, and off-cuts are recycled. The OSB facings are sourced from sustainably managed forests, and the panels carry BBA certification.
Oak itself is one of the most sustainable structural materials available — a natural, renewable resource that locks up carbon throughout its life. Pairing an oak frame with high-performance SIPs panels creates a building that is both low in embodied carbon and highly efficient in operation, supporting the UK’s net-zero targets.
Is a TEK Panel Oak Frame Right for Your Project?
Kingspan TEK panels are suitable for virtually any oak frame project, from a compact oak framed garden room to a full oak framed house or new build. They are particularly beneficial for habitable buildings that need excellent thermal performance, projects where build speed matters, high-performance energy targets, and buildings where you want the oak frame fully exposed on the interior.
At Sussex Oak Structures, we integrate Kingspan TEK panels into our design process from the outset, engineering the oak frame and panel system together as a complete building solution.
To discuss how Kingspan TEK panels would work for your project, get in touch with our team or call us on 01293 851287. We’re happy to talk through the options and provide a detailed quotation.
Frequently Asked Questions
What U-value do Kingspan TEK panels achieve?
Kingspan TEK panels achieve excellent U-values depending on panel thickness. A 142mm wall panel typically achieves around 0.21 W/m²K, whilst a 172mm panel can reach approximately 0.17 W/m²K. Both comfortably exceed current Building Regulations requirements. Roof panels are also available in thicknesses that meet or surpass the 0.16 W/m²K requirement for roof elements.
Can Kingspan TEK panels be used on both walls and roofs of an oak frame?
Yes, Kingspan TEK panels are designed for both walls and roofs. Wall panels fix to the outside face of the oak frame, whilst roof panels span between purlins or rafters. Using TEK panels for both creates a continuous insulated envelope around the entire building, eliminating cold bridging and maximising thermal performance.
How long does it take to install TEK panels on an oak frame?
Because panels are manufactured off-site to precise dimensions, a typical oak framed house can be enclosed within one to two weeks. This is significantly faster than traditional insulation methods, which require multiple trades and several weeks of work.
Are Kingspan TEK panels more expensive than traditional insulation?
The upfront material cost is generally higher than mineral wool or PIR board between studs. However, when you factor in reduced labour time, elimination of studwork, improved airtightness, and superior long-term thermal performance, TEK panels typically offer better overall value. The faster build programme also reduces total project costs. Contact us for a detailed quotation for your project.
