Upload your construction drawing and let AI instantly analyse your build-up. Get BR 443 compliant U-value calculations and Building Control ready reports in seconds.
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AI
Layer Detection
10s
Average Analysis
BR 443
Compliant
& Excel Reports
Our AI analyses your construction drawings in seconds, identifying materials, calculating thermal properties, and generating professional reports.
Drag & drop a construction detail, section drawing, or specification. Supports PDF, PNG, JPEG.
AI identifies all layers, determines thermal conductivity values, handles thermal bridging, and calculates your U-value.
Get professional PDF and Excel reports ready for Building Control submission. Full methodology included.
Our AI understands all common UK construction types and calculates compliant U-values automatically.
Cavity walls, solid walls, timber frame, SIPS, and more. Thermal bridging automatically calculated.
Typical: 0.15 - 0.30 W/m²K
Pitched roofs, flat roofs, warm deck, cold deck. AI handles ventilated cavities correctly.
Typical: 0.10 - 0.20 W/m²K
Solid concrete, suspended timber, beam and block. P/A ratio method included when needed.
Typical: 0.13 - 0.25 W/m²K
Generate documentation that meets UK Building Regulations requirements. Every calculation is transparent and verifiable.
All calculations follow the exact methodology required for UK Building Regulations compliance. Surface resistances, bridged layers, and material values from official sources.
Download Excel files with visible formulas. Building Control can verify every step of the calculation. Perfect for audit trails.
Professional PDF reports ready for Building Control submission. Includes methodology, assumptions, and Part L compliance check.
Instant check against Part L 2021 target U-values. Know immediately if your construction meets new build, extension, or renovation requirements.
Quick reference for Building Regulations Approved Document Part L
| Element | New Build | Extension | Renovation |
|---|---|---|---|
| External Wall | 0.18 | 0.28 | 0.30 |
| Roof (pitched, insulation at ceiling) | 0.11 | 0.16 | 0.16 |
| Roof (flat or pitched at rafter) | 0.11 | 0.18 | 0.18 |
| Ground Floor | 0.13 | 0.18 | 0.25 |
Join architects, surveyors, and energy assessors using U-Value.com for faster, more accurate thermal calculations.
"The AI analysis is incredibly accurate. I uploaded a complex timber frame detail and it identified every layer correctly. Saved me hours of manual input."
James H.
Architectural Technologist, London
"Finally, a U-value calculator that understands BR 443 properly. The PDF reports are professional and Building Control accepted them without question."
Sarah P.
SAP Assessor, Manchester
"We use this for all our Part L compliance work now. The speed improvement is remarkable - what used to take 30 minutes now takes 2."
Michael R.
Building Surveyor, Birmingham
A U-value (thermal transmittance) measures how effective a building element is as an insulator. It's expressed in watts per square metre kelvin (W/m²K) and represents the rate of heat transfer through a structure. Lower U-values indicate better insulation. Under UK Building Regulations Part L, all thermal elements must meet minimum U-value requirements.
Upload a construction detail, section drawing, or specification (PDF, PNG, or JPEG). Our AI analyses the image to identify all layers and materials, determines thermal conductivity values from BR 443 and manufacturer data, handles thermal bridging from timber studs or metal fixings, and calculates the U-value following BS EN ISO 6946 methodology.
Yes, all calculations follow BR 443 conventions and BS EN ISO 6946 methodology as required for UK Building Regulations. The calculator uses official design thermal conductivity values and applies correct surface resistances. Generated reports include full methodology for Building Control submission.
The AI can analyse all common UK construction types including cavity walls, solid walls, timber frame, SIPS, pitched roofs (at ceiling or rafter level), flat roofs (warm deck and cold deck), ground floors (solid and suspended), and more. Thermal bridging from repeating elements like studs is automatically calculated.
For new build dwellings: walls 0.18 W/m²K, floors 0.13 W/m²K, roofs 0.11 W/m²K. For extensions: walls 0.28, floors 0.18, roofs 0.16-0.18 W/m²K. For renovations: walls 0.30, floors 0.25, roofs 0.16-0.18 W/m²K. The calculator automatically checks compliance against these targets.
Yes, you can download professional PDF and Excel reports that are ready for Building Control submission. Reports include the full calculation methodology, material properties with sources, surface resistances, thermal bridging adjustments, Part L compliance status, and all assumptions made.
U-Value.com uses advanced AI technology to analyse your construction drawings and calculate thermal transmittance (U-values) automatically. Simply upload a section detail, specification, or construction drawing, and our AI will identify all the layers, determine appropriate thermal conductivity values, and calculate the U-value following BR 443 and BS EN ISO 6946 standards.
Our AI understands common UK construction materials and methods, including thermal bridging from timber studs, metal fixings, and other repeating elements. The system references BR 443 design values and manufacturer declared values to provide accurate results.
A U-value (thermal transmittance) measures how effective a building element is as an insulator. It's expressed in watts per square metre kelvin (W/m²K) and represents the rate of heat transfer through a structure. Lower U-values indicate better insulation.
Generate professional PDF and Excel reports that include full calculation methodology, material properties, surface resistances, and Part L compliance checking. These reports are formatted for Building Control submission and include all the information required to demonstrate compliance with UK Building Regulations.