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Energy Efficient Home Design… Retrofitting vs a New-Build iHus Annexe

Energy efficient home design is becoming increasingly important in this age of financial uncertainty and rising bill payments. In fact – according to a recent UK-wide study, 61% of potential buyers are now prioritising energy-efficiency when hunting down a new home.

New-build annexes are financially beneficial for a wide range of reasons; they lower the cost of care, share the burden of bills with the main dwelling, and add value to the property itself. However, they’re also more energy-efficient than older properties, and often cheaper to build than attempting to retrofit an existing property to the same standard of energy-efficiency…

Should I Retrofit My House?

On several occasions, the UK government has tried to introduce house retrofit schemes to improve energy-efficient home design, but older properties still fail to reach the standards of newer builds. This is due to the biggest gains coming from intensive retrofit programmes.

You can make quick, inexpensive improvements to reduce energy usage – however, these are often things covered by a new-build anyway. For example, every iHus features modern, LED lighting that is A+ rated, ultra-efficient and 90% more efficient than halogen alternatives.

Energy efficient home design includes retrofitting

What Does Retrofitting Involve?

In contrast to smaller improvements, a deep, radical or whole house retrofit involves a wide range of practices – taken alongside each other, to reduce a property’s energy consumption significantly. One key element of any retrofit project is high-quality insulation. This tends to include internal and external wall insulation, as well as roof, floor and cavity wall insulation.

Those opting for a new-build annexe with iHus will be pleased to hear we offer high-quality insulation as standard to drastically reduce energy consumption, and deliver A+ internal air quality. We also install green electric heaters and water systems to help eliminate emissions.

Here are just some of the ways we deliver energy-efficiency in our garden home builds…

  • Doors & Windows: A-rated PVCu doors and 22mm double-glazed windows are fitted to our annexes as standard.
  • Solar Panels: We’re always exploring new ways to improve energy-efficiency in our annexes. That’s why we now offer solar paneling as part of our core range.
  • Timber Frames: Part L compliant super-insulation, and FSC-compliant timber frame.
  • Lighting: Ultra-efficient, LED lighting is installed throughout every room as standard.
  • Ventilation: Our unique process exceeds current regulations – meaning our builds stay warm in the winter, comfortable in the summer, and well-ventilated year-round.

How Much Does it Cost to Retrofit a House?

Household retrofits are a significant investment for any property, but there are several factors that can increase these costs dramatically. For example, the price you can expect to pay will vary depending on the size of your home, its age, and its current rating for energy-efficiency.

Ultimately, what you invest in a retrofitting programme you would hope to get back through long-term energy savings. However – since the estimated cost of retrofitting a property could range anywhere from £40,000 to £200,000, this can take a considerable amount of time. As such, it’s more cost-effective to use those funds to downsize to an energy-efficient new-build.

Retrofitting vs Downsizing…

Not only do new-build annexes come at a much lower price tag than the thorough retrofit of an existing property, they’re also cheaper to heat. Before rushing into costly energy-saving renovation work, it’s worth asking yourself – do I really need all of this space? If you’re living in a larger property, but find several rooms have little to no use, it may be worth downsizing.

It might go without saying but smaller homes cost less to run, and benefit from a reduction in energy bills as a result. With less space to heat, those living in garden homes benefit from a reduced environmental footprint – and less waste within their water, gas and energy supplies.

With over 60 show homes up and down the country, why not put one of our annexes to the test yourself? Through our Open Hus scheme, you can view real customer show homes and discover the high-quality furnishings and well-heated buildings we produce across the UK. Click here to book a visit to a real customer home today

Retrofitting vs New-Builds…

New-builds typically have more energy-efficient home design than older properties as they have to abide by the latest building regulations. These rules have specifically been designed with carbon-neutrality in mind, so benefit from improved thermal performance and insulation.

In fact, according to the latest research by the Home Builders Federation, new-build homes are consistently ranked with much higher EPCs than existing households. In the year leading up to December 2022, 85% of new-builds received a rating of A or B for energy efficiency. In contrast, only 4% of existing homes achieved the same standard, with 51% rating D or lower.

Retrofitting older houses is possible, but they are typically revered for both their cultural and architectural significance. As a result, it’s often challenging to try and retrofit or heat them. While there are still hurdles to overcome, it’s far simpler to seek planning permission for new-build annexes on these properties. What’s more, the process is made easier with the help of an experienced team of planning professionals – such as we provide here at iHus.

It’s also worth noting that – even if an existing home is retrofitted for energy-efficiency, it’s still likely to require a lot more maintenance to upkeep in the long-run.

Energy Efficient Home Design in the Building Process

Those opting for the services of iHus benefit from energy-efficiency, not just in the finished build of their new home – but also in the construction process itself. From our first ever iHus, we set out to build in a cleaner, greener – and more energy-efficient way. By constructing most of our homes in our purpose-built premises, we reduce gas emissions by up to 50%.

Here are just a handful of the products, suppliers and building methods we use in our quest towards sustainable and energy-efficient home design.

  • Heating & Boiler Systems: Rointe radiators and water heaters are some of the most energy-efficient options on the market. With each product, trees are contributed to reforestation efforts, helping to reduce CO2 emissions, rebuild habitats, and more.
  • Flooring: Sustainable, quick-step laminate or vinyl flooring fitted as standard. These options are made entirely from recovered wood – sourced from sawmills, sustainable forest management and roadside maintenance, that would otherwise be burned.
  • Roofing: Flat EPDM recycled-rubber roofing fitted as standard, with the option to upgrade this to a pitched roof design.
  • Cladding: Durable, hard-wearing cladding, built to last and fully-recyclable after use.
  • Decking: Saige composite decking, made from 100% recycled materials.
  • Solar Panels: We now offer solar packages on our annexe homes which can significantly reduce energy bills, reduce carbon emissions, and increase the overall value of the property.

We’re Here to Help

Our expert team have more than ten years experience – and over 400 bespoke annexe constructions, under their belt. We’re aware of the financial struggle people are currently facing, which is why we’re always happy to advise on how an annexe might benefit you.

Simply get in touch with our friendly team to discover how we can help create an annexe space that you – and your family, can truly call home.

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Download our iHus annexe brochure

If you would like to download our annexe brochure please complete the form below. You call also request for a copy to be posted to your home address. Have any further questions, why not request one of our team get in touch?