How can we help you? An overview of our services


In recent months, we’ve spread the news about the Green Deal as much as possible. But did you know that Darren Evans Assessments has a huge range of energy efficiency services for domestic and non-domestic properties?

With years of comprehensive experience in all areas of sustainability assessment, we aim to offer a hassle-free, in-house service. We’ll take care of everything you need to meet legislation, with minimal inconvenience to you. We work hard to make sure the solutions we recommend are individually tailored to suit your project, and the most cost-effective on the market.

If you’re a landlord, housing developer, non-domestic property owner or just looking to renovate or extend your property, we can help.

Here are just a few of the top services we offer:

Standard Assessment Procedure (SAP) calculations

These measure the energy efficiency of buildings in compliance with Part L legislation. We work on all sizes of project, from new build homes and flats, to renovations and extensions. We provide free EPCs, can offer tailored feedback on how dwellings can pass Part L1A and L1B legislation, and have a cooperative approach to compliance and a turnaround time of only five working days.

Energy Performance Certificates (EPCs)

An assessment of energy efficiency and environmental impact, EPCs are a legal requirement for all property for sale, lease or rent in the UK. Your property receives a rating from A-G: the closer the building scores to an A, the more environmentally friendly it is. Our clients include social and private landlords, commercial and domestic letting, estate agents and home information pack providers. Call us if this includes you!

Code for Sustainable Homes (CSH) assessments

Since 1 May 2008, all new homes in England must have a CSH rating of at least 3 in order to receive planning consent. The CSH rating measures a decrease in carbon emissions and an increase in sustainability standards. To date, we have successfully certificated hundreds of dwellings under CSH level 3 and 4 and can help guide any customer through the process to successful certification. We offer a one-stop-shop CSH package that incorporates all the calculations, assessments and certificates you’ll need, and includes free site lodgement and free EPCs.

BREEAM assessment

BREEAM assessment measures a building’s energy efficiency, water usage, construction materials, water runoff and other sustainability factors. Most local authorities now require at least a BREEAM pre-assessment to be submitted at planning stage. Thanks to our wide-ranging experience, we are certified to help you with all aspects of BREEAM certification, and will go the extra mile to make the process as straightforward for you as possible.

Water calculations

Since 6 April 2010, all new homes and conversions are required to meet water efficiency targets. Building Control require proof that no more than 125 litres of potable (drinkable) water are used per person, per day. We can conduct the formal calculations required, as well as provide guidance on amendments that could be made to meet specifications. These might include installing rainwater-harvesting systems, reduced-flow taps and showers, more efficient toilets, dishwashers and washing machines, and smaller baths if necessary.

Thermal Bridging calculations

As building restrictions become stricter, calculation and assessment of thermal bridges throughout a building can have a significant impact on final certification. Our expert service will assist in meeting regulations by helping to maximise fuel efficiency and use less energy, and could replace or reduce the need for expensive renewable technology. We believe that thermal bridging calculations will become increasingly important as sustainability requirements increase, and will happily guide you through the process with no jargon and no hassle.

SBEM calculations

The Simplified Building Energy Model (SBEM) calculation checks the compliance of a new build commercial property with Part L regulations. We assess building materials; heating, lighting and power; and the use of renewable energy sources. We can make calculations for all sizes of project and will provide detailed feedback until regulations are met. We’ll also prepare your EPCs for free.

For a full list of our services, visit Or contact us directly, any time, on 01454 317940 or


Waste Water Heat Recovery Systems: A Technical Update


At Darren Evans Assessments, we always strive to keep abreast of the latest sustainable technology developments, to make our energy efficiency assessments as up-to-date and cost-effective as possible. Recently, we’ve investigated a number of Waste Water Heat Recovery Systems (WWHRS), and have been impressed with the results.

Waste Water Heat Recovery Systems reclaim heat that would normally be lost down the drain when you shower, or in any other situation where hot water runs into a drain. Using a copper counter flow heat exchanger, the heat from waste water is used to pre-warm cold water from the mains, meaning the boiler does not have to create as much hot water to shower. Up to 60% of the heat normally lost down the drain is reclaimed, meaning energy consumption per shower is significantly reduced.

At first glance, this technology presents several key benefits:

–  It is recognised by the BRE in SAP calculations, and can therefore be installed in new-build properties to help achieve Part L1A and CSH regulations.
–  In terms of performance, it achieves similar savings to Mechanical Ventilation Heat Recovery Systems in terms of SAP calculations, but is significantly cheaper to purchase, install and maintain.
–  It has been approved by the Water Regulations Advisory Scheme (WRAS), and is easily installed using common plumbing practises and fittings.
–  Once installed, it is maintenance-free.
–  It works all year round without being aspect dependent (as, for example, solar thermal technologies would be).
–  It represents a saving in energy bills and reduces CO2 emissions.

Manufacturers of the WWHRS ‘Showersave’ say that the system is likely to pay for itself within three years, and that over 2000 units have been installed so far in the UK.  Our experience with recommending and installing this technology thus far has been extremely positive, and we hope it will benefit our clients in the future.

Want to know more about our services? Call us now on 01454 317940, or read more about what we can provide at