Homeowners Professionals

Does a boiler cupboard need ventilation?

Although boilers are an essential part of our homes, more people are choosing to tuck them away into smaller spaces.

Recent research undertaken by npower showed that more than half of people surveyed (57 per cent) would want to knock £5,000 off the asking price of a property if it had an exposed boiler. That amount is more than the typical cost of a new heating appliance. The research also showed that 68 per cent of Brits would be put off buying a property if the boiler was uncovered.

Hiding a boiler is now easier than ever, as there are some types on the market that can fit into standard kitchen cupboards. But if you have a boiler installed in a cupboard or enclosed space, what kind of ventilation could be required, if any?

Although the boiler itself doesn’t require ventilation, the waste gases produced by the boiler need somewhere to go. They are expelled via a flue that leads outside. But what are the regulations when it comes to boiler positioning and flue ventilation?

What are the regulations of having a boiler cupboard?

If your boiler is positioned inside a cupboard, there are some clearance rules to adhere to. There should be a gap between the top of the boiler and the top of the cupboard. There should also be a gap   between the bottom of the boiler and the cabinet. You would need to check the installation instructions per manufacturer model for these figures. The clearance required with modern boilers can be quite low.

Although the  boiler cupboard  may not require any form of air vents or additional ventilation, the boiler requires oxygen in order to burn the gas correctly.  

The boiler should be easily accessible for any servicing or maintenance requirements. This means the door to the cabinet should be openable, and there should be a minimum gap of 700 mm between front of the boiler and a wall or other obstruction for the engineer to service it properly.

It’s more important that the flue is situated in the right position with correct ventilation. The flue is the pipe that allows the waste gases produced by your boiler to be released from your home. Your local heating engineer will be able to advise on the correct positioning.  

The boiler should be installed in such a way that the flue terminal is exposed to external air. It is important that this terminal doesn’t become blocked or obstructed and it must allow free passage of air at all times.  

If the boiler is in a cupboard and cannot be seen at all times it maybe an idea to fit a carbon monoxide detector, as a lack of oxygen could result in the production of carbon monoxide, which could be dangerous. This is why it is important that you have a qualified engineer fit the appliance.

What is a back boiler?

Back boilers were particularly popular in the 60s and 70s. 

Back boilers like a modern boiler contain a heat exchanger, but unlike a modern boiler which is usually on show or in a cupboard they were behind a gas or electric fire. Unlike modern boilers they were only around 78 per cent efficient at best, compared to the 98 per cent efficiency of modern gas-condensing boilers. Back boilers are rarely in use nowadays as modern houses do not have space for them. 

Does a back boiler need ventilation?

A back boiler may need ventilation, you should check with the manufacturer instruction for your model type.

How can we help?