Roof vents are far more than just an afterthought, in fact, they're essential for creating and sustaining the healthy function of your home. From counteracting the effects of changing weather conditions, to preventing damp and allowing moisture to escape, proper roof ventilation needs to be installed, particularly in modern, ultra-insulated and energy-efficient homes.

What Are The Advantages Of Installing A Roof Vent?

Although unique to every home, a great roof ventilation system can offer you the following...

  • A longer roof lifespan - ventilation helps to modulate the temperature of your roof and attic space, preventing damage from extremes of temperature, as well as protecting against damp and other problems by letting water vapour escape.
  • Saves you money - roof vents could help to save you money by regulating the temperature of your home, particularly in summer, allowing warmer air to escape and cooler air to circulate.
  • Prevents bad odours - lack of air movement and limited fresh air being recycled in your roof can lead to damp, musty smells that can find their way around your home. These bad odours are particularly apparent in summer but can also be apparent in winter as well, so it's important to have proper ventilation to counteract these problems.

What Roof Vents Are Available?

At Roofgiant, we have an entire range dedicated to roof ventilation, with products including Fascia & Soffit Vents, Vent Pipes, Fans, Extraction products, Turbines and more.

Here are just some of the most frequently used roof ventilation options available to you.

Universal Roof Tile Vent

This particular Universal Tile Vent from Klober has been designed to accommodate most concrete interlocking roof tiles, featuring a hooded cap with a moulded finish and made from tough, rot-resistant and flexible UPVC.

Plain Roof Tile Vent Terminal

This easy to install roof tile vent terminal is designed to be used with small plain non-interlocking tiles, as an in-line pitched roof terminal for mechanical extraction, soil and vent systems, where an external pressure test isn't necessary.

Universal Slate Ventilator

A must-have roof ventilator for any slate tile roof, this universal vent can replace one normal roof slate without being too noticeable or obstructing your roofline, thanks to the low hood design. It can either be used as supplied for standard slates or cut to size for smaller tiles.

Profile-Line Vent

Designed to mimic the look and profile of a tile, this quality roof ventilation option is made from high-performance UPVC in a range of different colours to suit your roof and can also be used at high or low level.

Lap Vents

An essential refurbishment product, the Manthorpe Felt Lap Vent combats condensation build-up by increasing the amount of ventilation into existing roof spaces. It is usually retrofitted into properties with additional loft insulation recently installed.

Flash Vent

A simple one-piece, roll-out, easy to fit sheet that provides ventilation for abutment roof details, this Flash Vent from Manthorpe includes a series of nodules as part of the design, providing airflow while acting as a fly screen.

Soffit Vent

Providing ventilation when used with a traditional fascia board, this soffit vent from Manthorpe comes with evenly spaced slots to guarantee sufficient airflow. The design is also narrow enough to keep large insects out.

Universal Over Fascia Vent

Our Universal Over Fascia Vent is designed to prevent excessive airflow resistance while creating a barrier against birds, pests and large insects. It provides a through-flow of ventilating air over the fascia board in both new build and refurbishment projects.

Vent Turbine

The Lomanco Turbine Set is made from an all-aluminium rust-free construction and is comprised of a low-maintenance, wind-powered turbine, designed to maximise ventilation capacity while also being geared towards going green. Comes with a square base that adjusts to a roof pitch of 0° - 27°

Ridge Vent

The Redland Universal Angle Ridge Vent is a smart, unobtrusive way of providing roof space ventilation at a high level and serves as a means of supplying ventilation to a soil ventilation pipe or mechanical ventilation system at ridge level.

TPE Flat Roof Vent

Made from a super durable and weather resistant thermoplastic rubber compound, this roof vent allows water vapour to escape from the structure, releasing vapour pressure, thus avoiding blistering of the membrane.

Bare in mind that different roof vent products require different installation processes so always check the product and technical information against the type of roof you own.

How Many Vents Do I Need For My Roof?

Following calculations from one of our suppliers, Building control services will often outline the airflow roof requirements - high level (ridge) or low level (eaves) - giving you the continuous airflow requirements in (mm).

To work out the number of vents needed for your roof, these airflow requirements (mm) need to be converted to the number of vents and centres for roof vents

Roof Ventilation Calculator

  1. What Is The Total Airflow Needed?
    Work out how long the ridge of the roof is in mm...
    Length in mm x the continuous airflow required.
    So... for a 10m long roof, requiring 5mm continuous airflow
    Calculate 10m x 1000 = 10,000mm long roof
    Then do 10,000mm x 5mm = 50,000mm2 airflow
  2. How many Vents Are Needed?
    Work out how many vents are needed to give you the same amount of airflow...
    Total airflow (above), divided by the amount of airflow per vent.
    Eg – for a CV20K vent with an airflow of 20,000mm2
    Calculate 50,000mm2(calculated above) ÷ 20,000mm = 22.5. (therefore 3 vents would be required if no half vents can be purchased from your manufacturer of choice)
  3. How Do I Calculate The Vent Centres?
    For working out how far apart the vents need to be...
    Calculate the length of the roof divided by the number of vents.
    e.g. 10,000mm length roof ÷ 3 vents = centres of 3,333mm.