Which is the Best Boiler for a 3 Bed House? Sizes and Types

In virtually all cases, the best boiler for a 3-bed house will be a combi boiler. Having one of those as the main component of your home’s central heating system will ensure a good balance between power, space-saving, and convenience.

Of course, you can always consider other boiler types, but combi boilers are the most common and effective solution for houses with up to 3 bedrooms and 1-2 bathrooms. Whichever boiler type you choose, you'll also need to consider the different sizes and models available. So, what is the best boiler for a 3-bed house? You will find the answer in this article.

To find out what boiler size you need for a 3-bed house, we recommend speaking to qualified installers who can give you expert advice.

It can take time to find experts you can trust though, after comparing reviews and waiting days for a call back. That’s why here at GreenMatch we’ve simplified the process!

Complete our short 30-second online form, and we can connect you with local, vetted and trusted installers. You’ll get up to 3 free, no-obligation quotes to compare.

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To recommend the very best boilers on the market, we looked at what the top manufacturers are offering in the UK. By assessing their models and comparing a few key factors, we picked what we believe are the best, and most suitable boilers you can buy today, for a medium household. 

We considered the following factors:

Understanding boilers can be a tricky business, but our list of the best boilers can be found later in this article to help you on your way. We also have some more detailed information on how to find the right boiler for your home below.

The best boiler for a 3-bedroom house will have an output between 18kW and 34kW. Homes with a single bathroom can utilise a combi boiler of 28-34kW. While those with 2 bathrooms will require a system boiler with 18-26kW.

The best boiler for a 3-bedroom house will need to be powerful enough to meet your home's heating and hot water demands. This means that if you choose either a combi, system boiler or regular boiler, it must have an adequate output size (measured in kilowatts, kW).

If the output size is too low, the boiler will struggle to run your central heating radiators, and the hot water delivered to your showers and taps might not be hot enough. On the other hand, if it is excessively high, you would pay considerably more for your boiler. Therefore, you might unnecessarily spend a lot of money on energy bills, making it no longer the best boiler for a 3-bed house you could find.

Also, the best boiler for a 3-bed 2-bathroom house will need to be more powerful than models designed to supply hot water for just 1 bathroom.

You can watch our short video below to find out how to calculate the right boiler size for a 3-bed house:

If you own a larger house, check our articles Best Boiler for a 4-Bedroom House and Best Boilers For Large Houses (5-7 bedrooms) to find the combi, system or regular boiler that best meets your needs. For smaller properties, we recommend reading What is the Best Boiler for a Small House?

What size a boiler should be depends on the number of radiators and bathrooms within a 3-bedroom house rather than the number of bedrooms. In any case, there is more than one right answer to the question of how many kilowatts (kW) a boiler should be to meet the heating and hot water demand of a 3-bed house.

One effective method to address the question "How many kW does a boiler for a 3-bedroom house need?" is to estimate around 2kW for each radiator in your residence. For example, a home with 6 radiators would require a boiler with a central heating (CH) output of at least 12kW. However, this is just a baseline, in reality, you may need more power than this depending on other factors.

Additionally, you must consider that combi boilers need to be more powerful than system and regular boilers to achieve the same result because they don’t store hot water for domestic use. Rather, they heat it and supply it to your hot water outlets on demand. This is why a combi boiler's technical specifications also indicate domestic hot water (DHW) output. 

You can check the table below to get an idea of how many kWs a boiler should be for a 3-bedroom house. Understanding what size boiler you need is a good first step when looking for a replacement.

Whilst all these tips and estimates can point you toward the right size, the only way to find out exactly what is the most appropriate boiler size for your 3-bed house is to get expert advice from a professional installer. However, finding the right installer could take hours of your time and effort if you opt to do the research by yourself.

Generally speaking, a combi boiler with a CH output rating of around 18kW is powerful enough for a 3-bedroom home. Similarly, a 13kW system or regular boiler can comfortably heat this type of property.

Regarding your home’s domestic hot water needs, a combi boiler needs a DHW output of around 40kW to meet the demand of a 3-bedroom house that also has 2 bathrooms. If the property has only 1 bathroom, then a lower DHW would be sufficient.

 On the other hand, system and regular boilers need a separate hot water storage cylinder as they don’t provide hot water on demand. Check the table below for estimated cylinder sizes.

Even though system and regular boilers are suitable options, combi boilers are generally best suited for 3-bedroom houses. As they don’t need external components (e.g. hot water storage cylinders and feed tanks), they can help you save a lot of space around your home. Nevertheless, we recommend a system boiler if your house has more than 2 bathrooms.

After reviewing dozens of models, we created a list of the best boilers for 3-bedroom houses. Below, you will find our 3 top picks for each boiler type. We considered high-quality units manufactured by the most reputable boiler manufacturers in the UK.

These are our picks for the best combi boilers for a 3-bed house:

A premium model in Worcester Bosch’s range, the 8000+ is a new release boasting a stylish exterior and a wide range of benefits.

These boilers certainly are among the best combi boilers for a 3-bed house. They include wireless connectivity with Bosch EasyControl,  a touchscreen display and an automatic pressure refill system.

Vaillant is one of the leading boiler manufacturers and a great option to consider for a 3-bedroom house, boasting a high efficiency and central heating (CH) output. Moreover, you can trust the reliability of this model as Vaillant offers up to a 10-year warranty. Below, we have compiled its main features:

The Vitodens 100-W is an efficient, compact, and quiet combi boiler suitable for medium sized homes. Its inbuild WiFi enables convenient controls and energy savings with Viessmann’s ViCare app. Its lengthy warranty also makes it a long-lasting, reliable choice. 

Our selection of the best system boiler for a 3-bedroom house includes the following: 

The Vitodens 200-W is a powerful gas condensing boiler. It is compatible with a 20% hydrogen blend and features quiet operation thanks to its low fan speed. Additionally, it includes an integrated WiFi interface for internet connection and a new environmentally responsible MatriX-Plus burner.

Similar to the combi boiler model, the Greenstar 8000+ 30kW system line is a new release. It offer the same benefits and special features as the combi, but when paired with a hot water storage cylinder, it can offer larger supplies and increased flow rates for homes with multiple bathrooms.

The Ideal Vogue Max system boiler is made in the UK with premium materials and includes Ideal's system filter - ensuring enhanced efficiency and protection. This boiler also offers built-in frost protection, quiet operation and LPG conversion for those not connected to the gas grid.

Whilst regular boilers are technically a valid option for a 3-bed home, we recommend installing a new regular boiler only if you already have one of these installed at home. 

They are more space-consuming than system boilers and much more than combis. On the other hand, a like-for-like regular boiler swap is usually cheaper than changing to a different type of boiler.

This is our selection of the best regular boilers for a 3-bed house:

The Greenstar 8000+ 30kW regular boiler is a highly reliable condensing regular gas boiler. Its main unit features a modern, compact design making it great for wall-mounted installation.

This is a high-performance boiler featuring excellent control and efficiency. The main unit is compact enough to fit in a kitchen cupboard and comes with a magnetic system filter to keep your home system clean and protected.

Ideal Logic Max Heat² regular boilers include a high-quality Ideal System Filter to enhance efficiency. They are manufactured in the UK by a British company, also making them more readily available.

At GreenMatch, we are committed to helping you navigate the transition to more sustainable ways of heating your home. In this regard, switching to low-carbon systems such as solar panels in the UK, heat pumps, or domestic biomass boilers may be the greenest choice. However, we know that these are expensive —and sometimes prohibitive— alternatives to gas boilers.

If you are not ready yet to switch but still want to make a difference for the environment, consider installing a highly efficient boiler.

New boiler costs for a 3-bed house might be high too. However, by replacing an old gas boiler with a new A-rated combi boiler for example, you could save up to £320 annually on your energy bills for a semi-detached house. It is important to note that savings will depend on various factors, such as the current energy prices and the size and thermal performance of your home.

Are you ready to embark on the journey towards increased energy efficiency, sustainability and annual savings on your energy bills? Luckily, GreenMatch is here to help by sparing you from the pain of spending hours of your time searching for vetted local boiler installers. 

Instead of spending hours comparing and calling installers one by one, choose the easy way and take advantage of our free and non-binding service.

Complete our short 30-second form, and we will connect you with up to 3 local professional boiler installers, so you can compare prices and find the best deal.

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