How Important is Air Tightness Consultancy?

 

Air tightness testing is where the air loss from the fabric of a building is measured. 

Most people think of air testing as a way to reduce their environmental impact and save money on their energy bills. But what you have to remember is that air tightness testing is part of the Building Regulations, so whether you’re looking to reduce energy waste or not, your building still has to comply. 

 

One of the most frustrating aspects of air tightness testing, for me especially, is that most air tests are carried out when the build is complete. Meaning that if there were any problems, it's not only harder to fix, but also more costly. Time is precious, we’ve all heard that on repeat, especially the older we get, but no truer word has been said, especially in construction. We must, as builders, construction specialists, engineers, etc, utilise our time better.  A construction designed with air tightness in mind will produce a more energy efficient build, and let’s face it, that’s what many of us are really aiming for. Not only is this better for the environment, but it will also cost less to run. 

 

There are many companies out there who can help design your build, ensuring it's air tight. Remember these engineers have had years of experience and can ensure you essentially build better and build tighter. By employing an engineer to look over your architectural drawings, it allows them to assess the construction for air sealing across the building envelope.  This will mean a full in-depth investigation of all product specifications to ensure they work alongside the target air test result. 

 

 

As construction begins, the specialist engineer will continue to make visits to ensure there are no problems. They typically look at junctions, different interfaces, vapour control layers, and the applications of all materials, to ensure that it is being built exactly to the requirements. Any problems, concerns, or even deviations from the plans, will be picked up early, meaning any remedial work will be completed quickly! 

 

It’s especially important if you’re hoping to produce an extremely air tight build that you undertake at least 2 air tests, one as standard, on completion. The other will be done first when the shell of the building is complete. But I would suggest and strongly recommend you get assistance throughout the whole process! 

 

Don’t forget, when talking about air tightness, you must also consider ventilation. An air tight build must have the right ventilation systems installed. This is yet another reason why you should employ the help of an engineer at the earliest possible stage. Air tightness will have a huge impact on other elements of the construction and you need all elements to work together!

 

What Affects the EPC?

 

I'm often asked, what exactly affects the EPC? How can I ensure I get the best results? 

 

The EPC. It is a vital piece of information that indicates what the typical running costs of your property will be. What you have to remember is that the better the EPC result, the more interest you'll get when trying to sell your property.  

 

A new build, or newer build, will be more energy efficient due to the updated building standards it's had to conform to. 

 

The construction of the build will also impact your results. Builds constructed before the 1930’s will likely be a solid wall construction, meaning no cavity. The problem is that the walls will not keep the heat in as well as a home with an air gap between the two courses of brick work, or if they have insulation in between.  This makes the build less efficient than a newer build, which has a developed cavity wall.

 

A property which is mid terraced will usually perform better than a detached build of the same age. The more walls exposed to the elements, the less energy efficient it will be. Also if your build has large rooms to heat, this can also have an impact. 

 

Loft insulation is the easiest and cheapest way to increase the energy efficiency of your build. The minimum recommended amount of insulation is around 270mm. 

 

Small changes, such as changing the lighting to LED light bulbs, might not mean a massive change in the results, but every little helps. If you're on the cusp, then this is a small change which might just bring you over the line. 

 

Double or even triple glazed windows will help retain the heat of your home, and in turn increase your EPC result. Most homes have double glazing, but why not take it up a notch and increase to triple glazing to make the most of your build? 

 

The controlled heating system will also impact your results.  There are many forms of heat controls, such as thermostats, programmers, and radiator thermostats (TRV’s). These will improve the efficiency of the property, because you can control the amount of heat used, and not waste energy where it is not required in your home.

 

The most important factor of an EPC is the energy source. Energy is obviously used to heat the property, and therefore will impact the EPC score. An example of this would be that a build using gas for heating will have a better result than a build using electricity for heating. The reason for this is that the unit for gas is cheaper than many other forms of energy sources, and is also less harmful to the environment when considering the CO² emissions produced in the process of generating electricity. However, we have so many new ways to heat builds now, such as Air Source Heat Pumps, where the energy is essentially extracted from the air. If you're in an existing build, your EPC will be based on the heating method you have installed. However, if you're looking to build,  consider the more energy efficient alternatives. 

 

The boiler is also another key factor that can affect the property’s score. There are various boilers with many efficiency levels. A boiler from the 70s will have an efficiency of around 65%, but newer boilers must have a minimum efficiency of 88%. Therefore, changing the old boiler for a new one will increase the EPC score, making the property more efficient. 

 

The EPC is vital to your build. There are many ways to ensure you get the best results, but to do that, you need to understand your systems, materials and construction methods. The best way is to get the help and advice of an expert at the earliest possible stage.