What Can I Do?


How do I know when I don’t have sufficient ventilation?

There aren’t always visible signs to give you clues to this. If there are dark areas on the walls or furniture where damp has formed, or worse you can see mould growth then it is obvious you need to re-balance your ventilation versus how insulated or closed your property is. Look through our Checklist to see if there’s anything you can do in your habits to improve things before you spend money.

How do I increase the ventilation in my property?

This depends on what you have fitted already but first of all make sure you have some form of ventilation. Therefore trickle vents in the windows or air bricks in the walls for background ventilation and fans in the bathroom and kitchen are a must unless you have a central extraction unit in the property.

What ventilation should I provide?

The Regulations have three different types/levels of ventilation:

Rapid or purge ventilation – this is the opening of windows when a lot of air needs to escape quickly, when painting or when you’ve burnt the toast.

Extract ventilation – this is traditionally provided by fans in kitchens and bathrooms when washing, showering or cooking is occurring, so that the steamy air can clear.

Background ventilation – continuous low level ventilation, many years ago a house would have been leaky enough, due to its construction, to provide this. In recent years, tighter houses require more specific solutions. It is now more common for window vents and air bricks to provide this in small amounts so that draughts don’t make living uncomfortable.

Over the last decade ‘whole house ventilation systems’ (more about them later) can provide Extract and Background ventilation in one unit.

Surely the air outside my property is full of pollutants, like exhaust gases, and they aren’t good for me?

Agreed, there are plenty of harmful pollutants outside but they disperse over a much larger area and therefore are generally not as harmful as air that has been left to ‘stagnate’ in a closed, sealed space.

I have a ventilation position on my windows where I can leave the window locked on a ‘night vent’ (ajar) position. Doesn’t that count as ventilation?

Yes it does but it isn’t allowed for in providing the correct levels of ventilation for the Building Regulations because different sized windows will let in different amounts of air when left ajar. It’s good if you use it sensibly, however the biggest drawback to ‘night vent’ positions is one of security. Your property can easily be broken into when the window is in that position. Windows can accidentally be left in the night vent position; anyone burgled having left a window open, even a little bit, hasn’t officially secured their property which would invalidate an insurance claim.

That’s why the recommendation is for trickle vents in the windows (see explanation). They ventilate without compromising the security of a property.

I have trickle vents and/or fans but I think I need more ventilation?

If these are fitted already and are not providing sufficient ventilation, check that they have been maintained correctly first. They may be blocked or in the case of fans not even connected to the outside of the building with ducting. You may need a plumber or electrician to help you find this out. If you are sure they are working properly, then go through our Checklist to see if there’s anything you can do to change your living habits to minimise the risk of condensation and mould growth. This will be cheaper than fitting a high spec ventilation unit.

What is a trickle vent?

A trickle vent, which is usually found at the top of a window, is a device which is designed to give low levels of constant (‘background’) ventilation without compromising the security of your property, which would be the case if a window was left ajar to do the same job. They are the most common form of background ventilation used when new homes are built to comply with the Building Regulations requirements for ventilation.

They should be offered as an option when purchasing replacement windows because new windows are more tightly insulated than the ones they replace, so the need for ventilation increases. It is often the case that replacement window companies do not offer trickle vents as they incorrectly think that the trickle vents harm the integrity of the window.

In some instances they can be retro-fitted to existing windows but this needs to be checked carefully, as a slot or series of holes need to be cut into the window material without damaging it or the glass. It is always best to have them built-in when the windows are being manufactured.

If you have vents in your windows already but think they are too draughty, even when closed, probably due them being plastic on a PVCu window, for instance, then they can be upgraded with improved vents. These vents would be metal and feature closure seals, which will reduce or eradicate any un-necessary gaps. Some vent models also have more adjustability, rather than just being fully open or fully closed, as this can make a difference to the amount of air entering the room.

It is worth pointing out that more than one vent per room may be needed to comply with ventilation regulations, so check to see what design suits your room or property best.

Trickle vents are available in a choice of colours to match the finish of your windows and/or window ironmongery.

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What can I do?