Technical Services

Approved Certifier of Design (Section 6)

Approved Certifiers of Design are qualified individuals allowed to certify the design of buildings in Scotland and to issue certificates in support of applications to local authorities for building warrants and amendments to warrants. ACDs are audited by their scheme provider and as such must maintain extremely high standards in their work.

Our experienced Approved Certifier of Design can certify your project meets Section 6 (Energy) of the building regulations. Their certification provides a guarantee that your building is not only designed to meet the requirements of section 6 but is designed to do so in the most efficient and cost-effective way to meet your requirements.

A 10% discount is applied to the building warrant application fees where a certificate of design is provided and applications are often dealt with in a more timely manner as there is no need for further checking by the building control officer.

PHPP Calculations

The Passivhaus Planning Package (PHPP) is a design tool produced by the Passivhaus Institute aimed for use by architects, engineers, and building designers when designing Passivhaus buildings. All Passivhaus buildings must be modelled in PHPP and the model assessed by the Passivhaus certifier at critical project stages.

The energy-efficient performance of Passivhaus buildings relies on an energy balance between losses and gains. The PHPP is used as a design tool to establish the energy balance which allows a space heating demand of ≤15kW/h/m2 to be achieved by analysing a variety of data including:

• Form, Orientation and Overshading
• Fabric Specification
• Heating and Hot Water Specification
• Ventilation Specification

We can use PHPP on Passivhaus, Enerphit and Passivhaus Equivalent projects, new build and retrofit projects, to compare varying specifications and products to optimise the performance of your building.

PSI Value Calculations

A large proportion of the heat lost in buildings is through the junctions in the building fabric where it is harder to maintain a continuous insulation line. These are the thermal bridges within the building and including amongst others:

• Ground Floor / External Wall Junction
• Window / Door Ingoes
• Roof / External Wall Junction
• Incoming Services and Duct Work

Our aim when we prepare construction details is to design them to be as thermal bridge-free as possible. PSI value calculations determine the heat loss or gain at building junctions, and we can carry these out on your project to assess the thermal bridging and develop details which minimise it as much as possible.

We can also use these bespoke PSI value calculations in our SAP assessment of your project which will highlight the reduction in space heating demand to assist in achieving compliance with Section 7 Aspect 2.

WUFI Calculations

The movement of moisture through the external fabric of a building is key to fabric performance. The proposed fabric must be designed and specified to ensure there is no build-up of moisture within the construction which causes condensation and mould and could lead to sick building syndrome. This is important in both:

• New Build Projects where the increasing levels of insulation can lead to a greater risk of moisture
• Retrofit projects where adding insulation to both the internal and external face of existing construction can lead to a greater risk of moisture.

A WUFI calculation is a dynamic hygrothermal simulation tool used to predict the movement of heat and moisture through a construction over time, if a construction does not allow for the correct movement of heat and moisture condensation risk occurs. We can carry out WUFI Calculations if required on your project to ensure the proposed construction will not lead to any risk of condensation. We can also liaise with product manufacturers to interrogate the results of the calculations and ensure the most suitable products are specified.

PAS 2035 Retrofit Co-ordinator

PAS 2035 is a British Standard for retrofitting existing dwellings. It was first published in 2019 in response to the Each Home Counts Review which highlighted systemic failures and poor standards in retrofit delivery.

PAS 2035 outlines how retrofit projects should be managed and delivered to ensure these failures do not continue to occur.

Our PAS 2035 Retrofit Co-ordinators have undergone the relevant training and can assist on your retrofit journey, being central to the process and ensuring compliance with the standard at all key stages:

• Retrofit Strategy
• Design and Specification
• Installation
• Post Installation

Our PAS 2035 Retrofit Co-ordinators will also be greatly assisted by the wider team and our wealth of experience on retrofit projects.

Dynamic Simulation Modelling (DSM)

Dynamic Simulation Modelling uses sophisticated computer software to assess the environmental performance of buildings. Similar to SAP and PHPP, the software models the building’s geometry, orientation and location alongside the thermal properties of the fabric elements and performance of the M&E equipment.

However, unlike SAP and PHPP, which are steady-state models, DSM models create a simulation of the building in real-time allowing more detailed and more accurate information to be obtained.

A DSM model is most useful when you want to develop a greater understanding of your building’s performance and energy use. We can develop a DSM model for your project to assess the following:

• TM54 Calculations – Evaluate the operational energy use of a building including regulated and unregulated energy
• TM59 Calculations – Asess the risk of overheating in your building and options for mitigating this
• Energy Use – Assess energy use in relation to CO2 emissions, peak demands, energy cost and utilisation of renewable energy
• Daylighting – Assess the predicted daylighting in your buildings to achieve sufficient levels