What’s The Best Combi Boiler For A 4 Bedroom House?

If you’ve been researching the purchase of a new boiler, there’s a good chance you’ve been overwhelmed by kw outputs, brands and quotes with huge (unexplained) price differentials.

In this guide, we’ll give you quick fire overview on specific models, warranty and explain exactly which the best combi boilers for a 4 bedroom house are.

This guide relates to combi boilers only. If you have a heat-only or a system boiler, you’ll want to use this boiler calculator to determine which is best appliance for your property; kw output will vary depending on what kind of boiler your system uses.

What Size Combi Boiler Do You Need For A 4 Bedroom House?

The problem with boiler sizing, is it’s not a one size fits all approach.

For instance, your 4 bedroom house might only have one shower, and 9 radiators. Another 4 bedroom house might have 15 radiators, a much longer heating run, and 2 showers.

All of this affects which size boiler you’re going to need. And, that’s why most installers want to come out and spec your property to ensure the boiler is the correct size, rather than billing you in the thousands for an incorrect boiler installation.

Too small? You’ll struggle to heat your home or use taps and showers at the same time.

Too big? Well, that’s just burning cash for the sake of it.

We used this quick-fire boiler calculator. In about 60 seconds, we got our suggestion (the first, being the most suitable) – the Viessmann Vitodens 050-W 35kW.

Heatable Viessmann Vitodens 050-W 35kW - best combi boiler for 4 bedroom house

A Note On Compact Boilers

If you’re looking to fit your new boiler in the existing location and its wall-hung, in a garage or large installation area like an airing cupboard, you won’t need a Compact boiler.

Fitting it in a small space like a kitchen cupboard? You’ll need a Compact.

Usually, a Compact is going to be around £100-150 more expensive than the equivalent boiler that’s not compact. You can compare prices between compact/non-compact on screen here.


Now you know what size boiler you need, the next thing to take note of, is warranty. Boiler prices vary considerably, and whilst some of the price differential will be simply due to different brand’s pricing, a lot will be associated with the warranty on offer.

For instance, you’ll get something like the Vokera Unica combi with a 5-year warranty. Other brands can be as low as 2-years, and we’d avoid them like the plague.

Realistically, 5-years should be your minimum target. 7 or more is ideal, (ironically, you’ll get that with something like the Ideal Logic Plus), but 10-years is certainly preferably.

You’ll pay a little bit more for that warranty (£100-300), but on a £3,000 ish installation, we’d take that extra warranty all day.

Ideal Boilers offer a boiler with a 10-year warranty, and for a 4-bedroom property, you’re likely to be looking at the Ideal Vogue 40.

Likewise, you can get a 10-year warranty on all Worcester and Viessmann boilers. That’s not the norm (5-10 years usually, depending on the specific model). If you jump over to the site offering the boiler calculator we mentioned above, that’s where you’ll find Worcesters with a 10-year warranty.

Why do they offer this extended warranty, compared with other installers?

Put simply, they’re 45% owned by Bosch, so get preferential treatment when it comes to prices, and warranty; you’ll get the same.

How Much Does A Combi For A 4-Bedroom House Cost?

The price of your installation will depend on the boiler you go for (i.e. a budget brand offering a short warranty, is going to be cheaper than a premium branded product with a long warranty), and the specs of your property.

We used a quick boiler calculator to get a price on the Vitodens 050-W and 100-W range from Viessmann, and you’re looking around the £2,400 mark there. You’ll be talking a similar price for something like the Ideal Vogue.

How Much Does A Combi For A 4-Bedroom House Cost

If you’ve got high hot water demand (2 or more showers, for instance) and a large heating run with lots of radiators, expect the price to be closer to £2,850 for a boiler with a 10-year warranty like the Viessmann Vitodens 100-W 35kW.

To get your exact price, you can plug in your property details here, and get a price on screen.

How Much Will My New Boiler Save Me On Energy Bills?

If your boiler is (just about) still working, you might be on the fence as whether to replace it or not. And that’s understandable, given the potential installation costs involved.

The first thing to do, is check the energy efficiency rating of your current boiler.

New boilers are A-rated, meaning they’re typically over 90% efficient. An old boiler could be as low as G-rated. In some instances, that could mean it’s LESS than 60% efficient.

There’s a quick guide on the Energy Saving Trust which outlines expected energy savings based on your property size, current energy rating, and the energy rating of your new boiler.

Long story short, those with a large 4-bedroom detached property and a (terrible) G-rated boiler, could be saving around £305 per year. That’s around £25 in your pocket every month, which is more than the cost of a new boiler on finance 😊.

But, you’ll also get additional benefits, such as a house and shower that warms up much quicker, not to mention peace of mind; no more boiler repair costs!

Still Not Sure Which Boiler To Buy?

If you’re using a local installer, they might offer Worcester Bosch boilers, they might not. Here’s a list of our favourite boiler brands in case they don’t offer Worcesters or Viessmanns.

Most local installers price keenly, but to make sure, you can compare their prices to other local installers here.

Or, if you’d prefer, you can get a fixed price online for a boiler with a 10-year warranty here.

What’s Next?

So, that’s it; our guide to prices and the best boilers for a 4-bedroom house.

Still got questions? Drop us a line via our contact page, and we’ll get back to you as soon as possible.

Not ready to buy your boiler just yet? Bookmark Heatingforce.co.uk and pop back soon. We constantly update our blog with boiler reviews, price guides and general advice.




Avoid Expensive Breakdown Costs
Boiler Replacement Promise: If it's under 7 years old and we can’t repair it, we’ll replace it.
Try YourRepair. From £9/mo
All plans include: annual boiler service, all parts and labour, unlimited support and 24hr helpline.

Fix things and tutorials

Get a Boiler on Finance

The best pay monthly packages available

Read guide
Heatable Boiler Replacement

Want a new boiler from HEATABLE?

Read guide
WarmZilla Boiler Replacement

Want a new boiler from WARMZILLA?

Read guide
Boiler Installation Costs

Confused about new boilers and their costs?

Read guide