New Build House – Renewable Energy Focus
Reasons for investing in renewable energy solutions are getting clearer each year, with the price of energy going up and the price of installing systems going down. Would you install energy systems if you knew how much money you could save in the long run?
One of our recent clients Adrian Cunliffe decided he wanted to make a change and reached out to us here at The Greener Group to fit his new build property with multiple renewable systems.
Adrian wanted to keep property running costs low whilst also having the latest technology, allowing him to reduce his energy bills by at least 50%. He said “I’m looking to protect myself from energy price increases in the future whilst also taking advantage of the government tariffs available right now. Another contributing factor was the environmental effect and doing my part to help reduce emissions and climate change.”
We’ve decided to talk through the entire process from start to finish of Adrian’s new build project and how we did it. This article uses an on-going new build project to demonstrate the process from procurement through to installation of a range of renewable technologies. It will be update regularly as the build progresses.
New build developments are currently one of the growth sectors in the construction industry. In many cases the architect, developer or site owner are looking to include renewable, green and low energy technologies into the build. This can be due to the latest building regulations specifications, the clients wish to reduce carbon emissions and save energy or the developer looking to add some attractive reasons to buy.
However, there is a range of options available to achieve these desires and it is not always obvious which technology should be used. That’s where we come in. The Greener Groups has been installing renewable energy products since 2010 and has gained a wealth of knowledge, experience and installation expertise across a range of technologies.
New Build Project – Self Builder
The project in question here is a single new build development, which has been commissioned by an individual as opposed to a developer or construction company. Adrian contacted us at the start of January 2017 explaining he was interested in a number of technologies for his new build development.
The old property was to be demolished in February and the new build to start imminently following demolition. As new build projects go, we were involved fairly late on. We often get asked to quote during the design and planning stage when drawings are being developed with the architects.
Adrian had expressed interest in using an Air Source Heat Pump (ASHP) to provide heating and hot water for the property, as well as Solar PV to supply electricity to the property and also the ASHP. The PV would be an on-grid system so not required to provide all the electricity to the property, just supplement it. Mechanical Ventilation and Heat Recovery (MVHR) to circulate the air, remove smells and recover otherwise wasted heat. Underfloor heating was also requested to provide space heating throughout the property.
Specifying Renewable Energy Products for a New Build Project
The first step to specifying renewable energy products for a new build property (or retrofit for that matter) is to gain an understanding of the property’s energy demands.
You would think logically that the larger the property, the bigger the energy demands. This is not necessarily the case and it all comes down to the efficiency of the building. This is based on the construction and fabric of the materials used and how much heat or energy they leak or use. A large well-insulated property could have a much lower energy demand than a small stone walled one.
New build property’s in the UK are becoming increasingly more energy efficient as a result of more stringent building regulations and homeowners having a greater appreciation of the benefits of energy efficiency.
Bearing the above in mind, we normally start the process with a set of plans being sent through from the client or architect. On this occasion, the plans were virtually the final draft when we received them. However, we often get involved with projects at the very early planning stages when the client is discussing options with architects. The plans supplied gave us not only detailed dimensional information but also accurate info on the heat loss of the property.
Each part of the property, walls, windows, doors etc has a U Value (a measure how effective a material is an insulator), which allows us to complete a heat loss assessment of the building and understand what kW is required to keep the property warm in cold weather. Combined with the hot water demand of the property, we can then establish what size heat source is required.
Current part L building regulations are such that new houses now must be fairly well insulated. For this build the client went beyond building regs and as a result the heat loss for the whole property was around 10.3kW. Based on our assessment, we proposed a Samsung Air Source Heat Pump with an output of 12kW at the design temperature of minus 2. The design also included a 400-litre domestic hot water cylinder with immersion back up.
Mechanical Ventilation and Heat Recovery
The first technology to install on a new build is often the MVHR system. The ductwork goes in before the ceilings; hence we have already completed the first fix for MVHR.
There are two main types of MVHR: Branch or Radial.
There are pros and cons of each. For this installation, Adrian has requested the radial type, which he perceives to be a better system than the branch type. The jury is out on this and there are pros and cons of each type of system. Both systems work effectively and the radial MVHR design does suit a property of this size.
The pipe design was completed through collaboration with the TGG engineers and Nuaire who are the MVHR manufacturer. Plans were submitted to Nuaire and a 3D design was drawn up and agreed with client and site manager.
MVHR First Fix – 24th July 2017
Following agreement of the design of the MVHR goods were delivered to site for the job to start.
Stage One is to run the flexible radial pipework from the location of the MVHR units out to each room. From any rooms with waste heat (kitchens and bathrooms) air will be drawn to the unit, filtered, heat recovered and then fed out to the living rooms and bedrooms. Installing the radial pipework is easier than the ridged branch type as it is flexible.
Ductworks on both floors were required to be installed during the first fix, which was around two weeks work for two engineers. Second fix will start once plasterers have completed.
Underfloor Heating Ground Floor – 6th August 2017
Following detailed design was agreed UFH first fix was booked in.
This involves installing all pipework on ground floor along with manifold and pumps. Main contractor arranged insulation for the floor, protective membrane and screed once pipes were laid. TGG installed all UFH pipework, stapled to insulation. Manifold was fixed to wall and pipework routed back following plan. Pressure test completed prior to screeding. Work to be started upstairs following plasterers in a couple of weeks.