Thermal Bridge Analysis (Psi Value Modelling)

Bespoke 2d & 3d Psi Value Modelling & Calculations

Thermal bridging is a major contributor to heat loss within buildings, typically as much as 30% heat loss occurs through thermal bridges in typical construction methods. Our assessors are able to design out thermal bridges and provide solutions to any junction or thermal bridge that will help lower heat loss, improve your SAP rating and of course improve the indoor thermal comfort levels for the occupants.

With the removal of Accredited Construction Details (ACD's) in 2022 designers and builders are now required to provide independent third party calculations for the proposed junctions and thermal bridges within the dwelling. Failure to do so will result in poor default values having to be assumed within the SAP calculation which will most likely cause most SAP assessments to fail the minimum fabric efficiency standards.

Typical thermal bridges included in most newly constructed homes include:-

  • Ground Floor / Wall Junction

  • Window & Door Openings (head, jambs & cill)

  • Intermediate Floor Junctions

  • Roof at Eaves

  • Roof at Gable

  • Flat Roof Perimeters

  • Internal & External Corners

  • Parapets

  • Party Wall Junctions

  • Party Floor Junctions

If you want to know more about Psi Value visit our Psi Value Explained page for a greater in depth look at the benefits of using Bespoke Psi Values.

Why Use BEAT?

  • Discounts for multiple junctions

  • We can provide both 2d & 3d Psi Value calculations

  • All calculations are in accordance with BRE BR 497

  • Experienced and qualified assessors

  • Expert Advice

  • Fast turnaround

  • Detailed reports provided in pdf format

  • A dedicated assessor from start to finish

Can I use Accredited Construction Details (ACD's)?


Yes, whilst these offer a slight improvement over the default values within SAP, these are being phased out in SAP 10 which is et to be introduced in 2022.




How long does it take to get a Psi Value calculation?


Typically a building will include around 10 or more junction types. On average it will take 3-5 days to calculate these. If you require these sooner we do offer a premium turn around service for a additional charge.




What do you need to produce a Psi Value Calculation?


We will need detailed construction details which confirm the specific materials being used and how they connect, abut or interface with one another. Typically a set of architects construction drawings and construction notes will provide us with sufficient information. We will require these in .dwg or .dxf format.




What happens if my detial is poor?


Our assessor are able to provide help and advice on how to imrpove the thermal performance of your detial should it be required.




What if I don't yet know how I'm going to construct a detail?


We can assist with recommendations to either improve a proposed construction detail or work with your architect from scratch to create a new one.




How much do they cost?


Typically to calculate one 2d Psi-Value will cost around £250-350+VAT. 3d Psi Values start at £350+VAT. Discounts are avaiable for greater volumes.





Frequently Asked Questions