Creating a cosy environment in your renovation project

When refurbishing a home to meet a modern lifestyle, reviewing your existing heating system is key. But before you make any decisions, you’ll need to understand your existing set-up and if you should invest in better insulation or new pipework too.  It’s a good idea to do your homework and ask specialists for advice to help you identify the best solution as well as the most appropriate size and specification.

Reviewing the existing system

The cheapest way to upgrade your heating system is to keep as much of the existing infrastructure as possible. That said, if your boiler is more than 10-years-old it may be time to replace it with a new, more energy efficient model. In most cases, the money you save in lower heating bills will recoup the cost, especially if you stay put for five or more years.

Ask a heating engineer to look at your pipework. Often there is no need to replace the pipework (which is disruptive and costly) when you’re upgrading radiators or boiler. But in an older property you might find imperial-sized or rusty pipework.  Installing a new, powerful boiler can lead to burst pipes and leaks if they aren’t up to scratch, as water is pumped around the house at a higher pressure. Similarly, radiators that haven’t been updated for 10 to15 years are likely to have internal corrosion and sludge deposits, hampering efficiency.

Updating a system

Some older systems will need a complete upgrade while other houses will already have the correct pipework and radiators fitted and may simply need to be flushed through to remove sludge. On average, the cost of replacing a gas central heating system for a three-bedroom house is about £3,500, including a new boiler and about nine radiators.  If you need new pipework, that could add around £1,000 to the bill. Some boilers need a water tank which cost about £200.

These are only estimates and prices will vary depending on the size of your home, choice of heating system and requirements.

Airtightness and insulation

Before you invest in a new heating system, make sure your home is well insulated. Does your house have solid walls or cavity ones which can be packed with insulation? The roof is often the main culprit for losing heat. Bear in mind a well-insulated home retains the heat better, so you may be able to meet your heating needs with a smaller and cheaper boiler or heat pump. Loft and cavity wall insulation are extremely cost-effective and can pay for themselves in a few years by savings on heat bills, say green campaigners.

If you are renovating a period property, you may have an architect on board who could advise you on the most sympathetic way to upgrade the heating system. Look for a local architect with experience of refurbishing heritage or listed properties. If you are lucky enough to live in a listed house, an experienced architect can advise if listed building approval is required when drilling holes in the building fabric for new pipework, for instance.

Condensing boilers

Building regulations stipulate that if you’re replacing an old boiler the new appliance must be A-rated for energy efficiency. Condensing boilers are more energy efficient because they extract heat from the exhaust gases that all boilers produce. A heat exchanger in the flue condenses the water vapour into droplets, releasing heat in the process. Vapour that comes out of condensing boiler’s flue can be seen as a plume of steam. By comparison, non-condensing boilers simply emit gases into the air and the heat is lost.

Condensing boilers are available in both combination and regular models. A ‘combi’ boiler will provide central heating and hot water on demand, firing up when a hot tap in the bathroom or kitchen is turned on. It will provide unlimited hot water. Meanwhile a regular boiler will heat a quantity of water which is held in a storage cylinder, usually in the airing cupboard, as well as provide for space heating.

Gas boilers

Government has plans to phase out gas boilers after 2025, but there are still plenty of supporters of this tech. If your house is connected to the national gas grid, mains natural gas boilers are usually cheaper to run than electric or oil-fuelled boilers. While carbon emissions for gas boilers are slightly higher than heat pumps or biomass boilers, the embodied energy in the manufacture and installation can work out less. Plus, gas boilers work well to reach the higher temperatures required for radiators and hot water as well provide warmth at lower levels for underfloor heating.

Biomass boilers

Biomass heating systems are typically fuelled with logs or wood pellets which can be low carbon if responsibly sourced. Most people buy a wood burning stove to help make their living room look cosy. But you can also connect the stove to a boiler to heat the rest of your home and provide hot water. Biomass boilers can be fitted with automatic hoppers to reduce the need for manual labour but be aware some set-ups require a dedicated plant room. Biomass boilers are eligible for the government’s Renewable Heating Incentive (RHI) which pays out quarterly cash sums based on your home’s space heating needs.

Heat pumps

Government is keen to get more people to swap gas boilers for eco-heat pumps as part of its mission to tackle climate change. These devices take energy from the heat or ground and convert it to energy at higher temperatures for domestic hot water and space heating. They work most effectively at lower temperatures, so are better suited to underfloor heating than radiators. Ground (but not air) pumps require a lot of garden space, so won’t be suitable for an inner-city terrace, for example. Houses that have heat pumps installed have lower fuel bills and smaller carbon footprints than other heating systems.  

Currently heat pumps cost on average £10,000 although experts say it won’t be long before prices are halved. Ministers are poised to dish out £4,000 grants from March 2022 to people who ditch old boilers for heat pumps. Most heat pumps will be eligible for RHI, which can pay back the current cost of installation within seven years.

Radiators vs underfloor heating

Most existing properties feature a radiator-based system. Replacing those with newer versions should be straightforward, particularly if they are the same size. Advantages of radiators include speedy response times and simple controls. Moreover, smart tech is now available to enable radiators to operate as efficiently as possible and be remotely controlled. Plus, there is wide range of styles available, including vertical space-saving options. On the downside, they are slightly less efficient than underfloor heating and likely to create hot and cold spots in a room.

Retrofitting underfloor heating can create a warm, efficient set-up even for older buildings. These water-based or electric systems heat the whole floor. They will warm up and cool down slowly over a longer period than the quick blast of heat of a radiator system. As underfloor heating operates on lower temperatures, it works best in a well-insulated property. Electric underfloor heating is usually cheaper to install then water-based systems, but the running costs are higher, so it is more suitable for smaller spaces, such as a bathroom.

Heat source options

If you are refurbishing an older property, you may well want to upgrade your heating.  First consider your current system and then what’s available and feasible. Next weigh up the pros and cons of each system. Don’t only consider the installation costs but look for a system that will keep your bills low, perform efficiently and be easy to maintain. Decide on your priorities. For example, low upfront cost versus low running costs versus minimising your carbon footprint.

If you are looking for help with any electrical issues, you may find some of these services useful: