Retrofit, warming to heat pumps: Cut your utility bills with home retrofits
If your home is insulated to the right level and has low heat loss (HLI) with managed ventilation, it may be ready for a whole, new sustainable heating system.
The SEAI in their effort to transform the way we use energy, advise us to: assess our needs, insulate, and then and only then, to add renewable energy technologies (heat pumps, solar water heating panels or solar photovoltaic panels). Delivering a snug box that holds heat inside our homes, insulation is first, last and always in any serious energy renovation.
Maybe in the starry future, we will rip out our heat-pumps in favour of Kryptonite. Still, no CH system of any kind can be optimal without a tight build matched to high levels of insulation to hold the heat in, and effective ventilation to guard air quality and defeat condensation.
Starting with attic insulation. If your home is a sieve, leaking energy through the envelope, low U-values of 0.16 W/m2 K for ceiling level insulation and 0.20 W/m2 K for rafter insulation (where needed), will deliver perceptible changes in comfort levels downstairs on the very first cool day outside. Tackling just the walls and the roof in a home with a poor BER, insulation measures could save as much as €600 on your energy bills.
We might assume it’s up to scratch, but tucked out of sight in an area of the home we rarely explore – compressed, ragged, thin and gaping – is that failing fluff truly acting as the hat on your house? 20% to 30% of your heat may be migrating straight out to the heavens through a historic installation of 100mm.
Improvements through attic insulation are described by the SEAI as “the most cost-effective upgrade made to a house”, and grant aid is more than generous, covering up to 70% of the capital outlay. Today’s standard for roll and bat insulation to the floor of your attic is 300mm – that’s relatively deep and generally well over the joist depth.
Attic insulation grant aid ranges from €800 – €1,500. There is extra grant help for rafter insulation (for say pitched ceilings) offered as part of One-Stop-Shop route at €1,500 – €3,000. The choice of material will depend on the depth and pitch of your joists and rafters.
Your contractor should survey the level of ventilation in the attic, advise on lagging pipes in your newly chilled loft spaces, and should install a permanent walkway for easy access to cold water tanks, solar-PV elements, or other fitted appliances, without compromising the thermal integrity of your insulation. Individual grant aid, here as with all individual grants is retroactive, and paid back to the home-owner on the certified completion of the work, and the completion of a published BER. With building material prices in flux, you should study the full estimate from your potential suppliers for attic and rafter insulation (rigid foam) before applying for SEAI grant assistance and starting work.
The rest of the structural envelope making up your home’s protective thermal exoskeleton are the floors and the walls. Ideally, we want our home to feature a continuous layer of insulation throughout, without gaps or thermal-bridging where there are changes in materials. Insulation upgrades to downstairs floors are only generally addressed in determined full-house renovations. The work is otherwise extremely disruptive and expensive. Using the One-Stop-Shop device of a full holistic retrofit, the installation of UFH is often a winning opportunity when married to an energy efficient heat-pump in a new CH system. €3,500 of grant aid is available to insulate such floors.
Even old, chill, damp and empty walls can be given improved density, providing an impressive defence against heat loss, and achieving remarkable U-values of 0.27 W/m2 K or better. There are three approaches – all of which can be set the two grant streams or applied for as Fully Funded Energy Upgrades. These methods can be used alone or even combined with supporting grant-aid. The least invasive, hassle-free wall insulation hit, is cavity fill. A popular grant aided adventure for its cost-effective, and immediate impact, cavity fill eliminates the gap between the internal and external leaf of block, which unchecked can allow damp and cold to cross over into the house.
Cavity fill will not stop damp or rising damp, and if you find these kinds of problems and you are managing your own improvements, get advice from a qualified builder or engineer. Grant aid amounts to €700 – €1700 depending on house type. Grant aid for internal dry-lining (€1,500 – 4,500) and external-wall insulation (EWI) (€3,000 – €8000) is again open to both One-Stop-Shop applicants and individual grant aid applicants. These are serious structural projects for all house types, with considerable additional buildings costs to be aware of. EWI, is termed “the wrap” for its powerful impact on heat loss, cloaking the house against ingress of weather and preventing energy created in the house slipping outside the envelope. With the transformation of more than 25% of the external walls of the house (this is often a handsome re-imagining that will also address rain penetration, poor air-tightness and frost damage) - you should apply for planning permission – your contractor can advise.
Investigating any insulation job, we need our contractor to clarify if the quotation covers all costs associated with the works. Building materials, contractor fees and skilled trades are at a historic high. Using Individual Upgrade Grants, contact more than one SEAI registered firm, and tender as you would for any other building or renovation project. If you plan to replace windows with double or triple glazed units, keep in mind that the SEAI grant aid is confined to the One-Stop-Shop process with its fully managed solutions and wider grant selection. Grants €1,500 – €4,000 depending on house type. Explore the excellent SEAI PDF guides to these and all grant and non-grant aided energy improvements.
Using the One-Stop-Shop mechanism, the ultimate goal on completion of a deep energy retrofit, is currently the installation of a heat pump (air to water, air to air, geothermal or water sourced).
Near Zero Energy (NZEB) living can reduce space and domestic water heating to a fraction of the cost inevitable with a shoddily insulated home limping along on unsustainable fossil-fuels like kerosene. However, a heat pump system is not a plug-and-play replacement for a boiler. It’s inclusion only makes sense on the completion of highly specific works towards a heavily insulated, carefully sealed building with a BER of B2 or better, with predictable, regular air exchanges.
Susan Andrew, Campaign Marketing Manager for the SEAI explains, “Many homeowners are actively looking to move off fossil fuels and invest in renewable energy systems. If your home is well insulated, then you should really consider replacing your old oil or gas boiler with a heat pump. Homeowners often think heat pumps are too expensive to install, but with more products available on the market and with heat pump grants of up to €10,500 from SEAI, they are now more attractive than ever.” If your home is leaching heat through the roof, walls, windows and doors, a heat pump will helicopter your electricity bill to nerve-mincing altitudes. Low heat-loss values, through superb insulation upgrades and managed ventilation, are vital to the success of whole-house, holistic energy upgrades.
The background heat of a quality, perfectly commissioned heat pump, warming the air over long periods, potentially married to UFH or appropriately sized radiators, can provide a fresh, healthy environment year-round. Even temperatures in every room will be nothing short of life-changing for homeowners completing their sustainable journey.
With a home detailed to a high standard, heat pumps can operate at startling 200% – 400% efficiencies, and zero carbon emissions at point of use. Only natural gas (a fossil fuel) can touch the economy of a HP. To ensure that a heat pump is appropriate and cost-optimal for your project, there’s a dedicated SEAI Technical Assessment for every application for a HP grant. This expense can be redeemed during the One-Stop-Shop grant award when your system has been completed and commissioned by your SEAI registered installer.
Moving onto another renewable, together with variously priced insulation measures and the installation of proper heat controls (up to €700 of grant aid from the SEAI) solar PV is a superb stand-alone, green energy source. If your roof is in good order, the installation of PV-solar panels is not dependent on other renovation work and has recently been freed of most planning permission constraints. Prompted by the instability of our energy prices, solar PV property upgrades are already up a massive 231% over last year, rising to 10,554 at the end of July.
Brian Looby, Solar PV Programme Manager remarks, “Rooftop solar PV is best suited to homes that have a southern orientation but is also feasible on homes with an East/West orientation. Ideally the home should have little or no shading from surrounding trees or buildings. In terms of energy use patterns, the home that has a steady demand for electricity throughout the day stands to benefit most from solar PV, for example where people are working from home during the day.” Once designed to optimise your energy gain, and with grant aid in place with an SEAI registered firm, your PV-solar system can be installed and up and running in as little as one day.
PV-Solar grant aid is offered in both grant streams and should be considered following an on-site or well considered remote survey. It’s vital to manage expectations for your home, its aspect, its roof type and to be apprised of the influence of shading obstacle between you and a long arc of solar gain over daylight hours.
Environment Minister Eamonn Ryan, announced in April, that the VAT on the supply and installation of solar PV systems on homes and public buildings was being removed. This adds as much as €1,000 of saving on a 4.5kWp PV array, using a supply and installation cost of €8,000. Snipping off the maximum SEAI grant of €2,400 for 4kWp on the slates, your costs would start from around €5,600 depending on the inclusion of a battery and whether you opt for a solar water-diverter to heat some of your domestic demand.
Now that the Microgeneration Support Scheme (MSS) is up and running a battery is not essential to save serious money on your energy bill PV solar energy, as you can generate and sell back excess gain to the Grid during the day. The MSS allows for all types of meters through actual or assessed gain for your size and orientation of solar PV array. Farming your own solar gain, you can off-set the cost of grid kWhs used after daylight hours. The kWh credits paid directly back to your bill, can take a tasty bite out of those obligatory standing charges.
For more information on a host of sustainable improvements, many SEAI grant-aided, please visit seai.ie. The Vacant Property Refurbishment Grant provides funding to refurbish vacant and derelict homes and can be combined with SEAI grant aid. It can also be used to renovate properties that have not been used as residential properties in the past. For more information contact The Vacant Homes Officer at your local authority (gov.ie) or call the Housing Agency's Vacancy Phone Line on 1800 000 024. Fully funded energy upgrades are available, for qualifying homeowners in receipt of certain welfare benefits, seai.ie
