Thermal bridging
calculations.
Bespoke 2D Psi-value and fRsi calculations for SAP assessments and building control. Clear reports, useful advice and someone you can talk to.
£150 for your first junction. £100 for each additional detail.
The detail makes the difference.
Your construction, modelled as it is designed.
When the standard detail isn't your detail.
A different roof edge, a change in insulation or a window sitting further back in the wall can change how a junction performs. We calculate the actual detail, so your assessor has a supported value to use.
A struggling SAP assessment
Thermal bridging can make a worthwhile difference to fabric performance. We can work with your SAP assessor to identify useful junctions to calculate and explain practical improvements.
A detail that needs its own value
If your construction doesn't match an available detail set, we can produce bespoke Psi-values for the junctions you are actually building.
Surface temperature evidence
Need an fRsi calculation for building control? We assess the junction temperature factor and explain its surface condensation and mould risk.
A useful result.
A report you can use.
We produce 2D calculations to BS EN ISO 10211 and BR 497 conventions, with the detail, inputs and results documented for your SAP assessor and building control.
Advice and reasonable minor revisions are included. If a detail needs more work, we'll explain why and help you understand the options.
More about fRsi- Psi-value for your junction
- fRsi temperature factor and assessment
- Illustrated calculation report
- Model geometry, materials and assumptions
- Practical advice and reasonable minor revisions
Straightforward pricing.
Helpful by default.
One set of prices whether you're planning ahead or trying to get an assessment moving. Send your details and we'll confirm a fixed fee before starting.
See prices and variations- First distinct junction
- £150
- Each additional detail on the same project
- £100
- Variation of an existing model
- £50
From drawing to calculation.
1.Send your details
Share your junction drawings and construction information. Tell us what your assessor or building control needs.
2.Agree the work
We'll confirm the junctions, the fixed fee and when you can expect your reports. If something is missing, we'll let you know.
3.Get your results
Receive the calculations and reports, with clear advice on what the results mean. We can speak directly to your assessor if it helps.
Specialist calculations. Practical support.
We combine SAP assessment experience with qualified 2D thermal bridging modelling. We understand how junction performance affects the wider assessment and help you make sense of the results.
About usWorking with assessors and architects
Need a dependable contact for bespoke junctions? We can work alongside your practice, use your drawing references and keep the calculations organised around your project.
Send us a projectA few common questions
Do I need every junction calculated?
Not necessarily. Your assessor may already have suitable values for some details. We can help identify which junctions need their own calculation.
Can you guarantee a SAP pass?
A bespoke calculation gives a supported value for the actual detail. Its effect on SAP depends on the result, junction lengths and the rest of the building. We'll help you assess where it can make a useful difference.
What counts as a variation?
A change to an existing model, such as a different insulation thickness or material. An overhang and a parapet are different junction details. We'll confirm how each drawing is priced before starting.
How quickly can you turn it around?
Tell us your deadline when you send the drawings. We'll confirm a delivery date with your quote, based on the details and our current workload.
Do you carry out site surveys?
This service is based on your drawings and specifications. Thermal imaging and on-site investigations are not part of the calculations.