What are roof soffits

 This part of the article explains all the basics of soffits, detailing what they are, where they go, the materials they can be made from, maintenance, what they are for and more.

Soffits are situated on the main area of the roof. They can be used on stairs and under porches also. They are commonly made of uPVC but can also be made from fibre, steel, wood and cement if desired. However, uPVC is the material most favoured today, as it is the most resilient material and is more affordable than metal materials. UPVC soffits withstand most weather and do not need to be painted often, whereas wood soffits do. They are quite similar to all other soffits just with some benefits. Soffits help your house to look aesthetically pleasing while also serving the practical purpose of protecting the rafters from the weather. Without a soffit your roof would rot and go mouldy over time, which is costly to repair and very difficult to get rid of without professional help. UPVC soffits are also available in many different colours so you can choose the perfect colour to match your home.

Furthermore, soffits are essential to the airflow of a building as they come in vented varieties. They help air circulate around the building yet stop moisture, so the building does not get damp. This is extremely important because moisture is created by simple home activities like cooking, washing clothes and showering and if it cannot escape it will become condensation inside the building and create damp.

UPVC is a favoured material for soffits because it is affordable compared to aluminium and steel, it has amazing insulating properties and it does not rot over time. As previously mentioned it is also available in different colours and finishes. It is the easiest material to clean and resistant to water which is very useful.

How many soffit vents do I need?

This section discusses how many vents you will need and how to decide.

This is a difficult question to answer when ventilating older roof spaces, and I’ve seen many people try to take the one size fits all approach over the years, sometimes they are right, sometimes they are wrong.

The short answer is that every building is different, not only by shape and size but by geographical location and positioning, even in the same street. This makes a one size fits all approach hard to achieve. For example.

House one – A standard semi-detached home. This is located five hundred meters down the road from house two (see below) and placed in a row of other semi-detached houses. It has continuous soffit vents all round, and two roof vents front and back. And it has great ventilation in nearly all weather.

House two – Another semi-detached house identical in every way to house one. This house though is an end semi-detached house and is located five hundred meters up the road placed on a slight hill. The wind channels through the estate, up the road and blows violently into the vents and soffit vents. So much that it often blows back the insulation in very strong winds, this causes heat loss from the insulation near the edges of the roof in winter, creating mould and black stains.

Do you see the issue?

So, if you are unsure call an experienced architect or roofer to evaluate. Personally, I would suggest being cautious. A little extra ventilation is easier to add later than it is to remove. You do not want to end up with your roof void being too cold, warm air can hold more moisture than cold air and this will evaporate moisture from your insulation better, reducing the heating bills.