HEET (Home Energy Efficiency Tees Valley)

 

Loft or roof insulation

Up to a quarter of heat lost is through a property's roof. Installing insulation in your roof or loft is a great way to reduce heat loss and make your home more energy-efficient.

The thicker the roll of insulation used, the less heat loss there will be. So, even if you already have loft or roof insulation in your home, it’s worth checking if it could be further improved and thickened. Ideally, the thickness of your loft insulation should be between 250mm to 300mm.

Cavity wall insulation

In uninsulated homes around a third of heat loss is through the walls. This is particularly an issue in homes with cavity walls which are made up of two walls (the outer usually brick; the inner usually brick or concrete) with a gap between them. Cavity wall insulation reduces this heat loss by filling the gap between the two walls – the ‘cavity’ – with insulating material which prevents or reduces the leakage of heat.

How does cavity wall insulation work?

The most common method for fitting cavity wall insulation is for insulation material to be injected into the cavity – usually mineral wool, polystyrene beads, or polyurethane foam. This is done by drilling small holes in the outside walls at various intervals, injecting the material through the holes, and then filling the holes back up so they are not noticeable.

What homes does this measure suit?

Cavity wall insulation is only relevant for homes which have cavity walls. If your home was built after the 1920s, it will likely have cavity walls. If your home was built before 1920 it will probably have solid walls, and so solid wall insulation is more relevant for you.

Some homes with cavity walls will already have them insulated – it was common practice from the 1990s onwards to add insulation into cavity walls during construction.

Cavity wall insulation is not suitable for flats, unless you have agreement from the owners of all flats in your block to insulate the whole block.

Under-floor insulation

Floors on the ground-floor – alongside walls and roofs – are a common area in a home that heat is lost from.

Floor insulation usually refers to the installation of insulation material around the floor space on the ground-floor of a property. However, if you have floors on upper floors which are above unheated spaces, such as a garage, you could be losing heat here too and, therefore, require insulation.

Heat loss through floors is more pronounced in homes that have ground-floors made of solid concrete, which is the case in most new homes. These can be insulated by adding rigid insulation boards on top of the flooring. It can also be insulated internally but this will require replacing the concrete floor and so is best done when the flooring already needs replacing.

Older homes may have suspended timber floors. If you have such a timber floor you will likely be able to see air bricks or ventilation bricks on the outside walls of your home that are below floor level. It may seem the obvious solution to insert insulation into these air bricks to close the gaps, but you should never do this. These air or ventilation bricks are needed for ventilation to stop damp and prevent  the floorboards from rotting.

External/internal wall insulation

Un-insulated homes can lose around a third of heat through their walls. The best way to reduce heat loss through walls depends upon the type of walls in your property.

Solid walls have no gap and cannot be filled with cavity wall insulation, but they can be insulated by adding insulating material to the inside (Internal Wall Insulation or IWI) or outside (External Wall Insulation or EWI) of the wall .

How does solid wall insulation work?

Internal wall insulation can be done by fitting rigid insulation boards to the wall. It can also be done by building a stud wall – a timber frame which sits in front of the solid wall. The gaps in the frame are then filled with insulation material such as mineral wool fibre. This will slightly reduce the floor area of the room. You’ll also need to ensure any issues with damp are dealt with prior to undertaking the work.

External wall insulation involves a layer of insulation material being attached to the wall on the outside of the home. This is then covered with a special type of plasterwork or cladding which can be decorated over. This is a less disruptive procedure than internal wall insulation. It also has the added benefits of improving weatherproofing and sound resistance, as well as protecting the brickwork and so expanding the lifespan of the walls. However, it may require planning permission, depending on your local council.

Double-glazed windows

Windows are a key heat loss area within a home. Heat loss can be reduced through draught-proofing to fill any gaps as well as ensuring that windows are double or triple-glazed. As well as reducing energy bills and carbon emissions, this will also reduce noise from outside..

How does glazing windows work?

The energy performance of a window depends on how well it stops heat from passing through it, how much sunlight travels through the glass and how little air leaks around the window. Single-glazed windows are not very effective at stopping heat loss,as they are made of a single pane of glass.

Double-glazed windows are windows which have two sheets of glass with a small gap between them. Triple-glazed windows have three sheets of glass and two gaps, improving insulation further.

Windows can be made of many different materials, which have differing impacts on the energy performance of the property. These are measured using an energy rating called a u-value, on a scale from A++ to E.

When replacing windows, it’s very important to consider ventilation too. More efficient windows will likely lead to more condensation due to reduced ventilation – so you need to incorporate vents in the replacement windows.

Air Source Heat Pumps

Air source heat pumps (ASHPs) absorb heat from the air outside and use it to heat your home and hot water. They use electricity to run, but the heat output is much higher than the electricity input – so they’re a very low carbon and low-cost form of heating.The Government is hoping to roll out 600,000 heat pumps per year by 2025, and all new homes will have an air source heat pump installed by this time.

How do air source heat pumps work?

Heat from the air is absorbed at low temperature into a fluid. This fluid passes through a compressor, increasing the temperature, and transfers that higher temperature heat to the heating and hot water circuits of the house. Air-to-water pumps absorb heat from the air and transfer that heat into water, which is then distributed around your home via a central heating system. This is the most common form in the UK.

What homes does this measure suit?

Air source heat pumps are not right for every home. They suit homes which have enough space outside the home where a unit can be fitted to a wall or placed on the ground, have an existing central heating system and are well insulated and draught-proofed to minimise heat loss. If you aren’t sure whether an ASHP is right for your home, we can discuss this further when your property has had a survey.

Rooftop solar panels

Solar photovoltaic (PV) panels take energy from the sun and convert it into electricity which can be used to power your home. Even on dull days, your will still be able to generate electricity.

By installing solar panels on the rooftop of your home you can generate your own renewable electricity, meaning you reduce your energy bills (as you need to buy less electricity) and the carbon footprint of your home.

A typical solar PV array on a home rooftop will save 1.3-1.6 tonnes of carbon emissions every year (Energy Savings Trust).

If you let your energy company know that you have installed solar panels you should qualify for SEG (Smart Export Guarantee) and you may see reductions in your energy bills and receive payment from electricity suppliers for electricity exported back into the National Grid, providing certain criteria are met.

Solar Battery Storage

You don't need to install a battery for your solar panels to work, but a battery can help you get the most out of the energy your panels are generating.

Solar panels will create energy when there is daylight and you can use this solar electricity instead of buying it from your energy supplier. However, these panels don't work at night time (when you tend to use the most energy). So, what happens then?

If you don't have a battery you'll switch back to using energy from the national grid overnight which will cost you money. If you have a battery installed you can use any extra energy stored in the battery at night time. This reduces your reliance on the grid for electricity.

The battery system is designed to be wall or ground mounted and is usually installed in the loft of your home. For homes without a loft, the installer will be able to give you alternative options, such as your garage or under the stairs.

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The importance of ventilation

When we think of energy-efficiency we may initially think of how to keep the heat in to reduce wasted energy. However, it’s just as important to look at ventilation in your home.

Poor ventilation leads to issues with condensation and damp as there is poor air circulation in the home. Controlled ventilation will reduce this, letting fresh air in when needed.

There are a few types of ventilation measures within the home, including:

• Extractor fans in rooms where moisture is commonly produced, usually kitchens, bathrooms, and utility rooms. These need to be used at all times when moisture is being produced.
• Under-floor grilles or airbricks which help keep wooden beams and floors dry by allowing gaps in which air can circulate.
• Wall vents which allow small amounts of fresh air into rooms.
• Trickle vents which are usually found above modern windows where small vents allow fresh air to trickle in.

Ventilation should always be at the front of mind when undertaking any energy-efficiency work in the home. Measures such as insulation and draught-proofing, if not done correctly, can cause issues with ventilation, leading to damp in your home.

At HEET, one of our qualified surveyors will complete a full holistic house inspection before any insulation measures are carried out, meaning that your home can breathe and you can be assured that the works are carried out to the highest standard.