How to fit Fascias and Soffits


Completing a roof renovation is a laborious but rewarding task. Once you have tiled your roof and installed your roof windows it is time to finish off your roof with a roofline. This involves fitting fascia and soffit boards, but what are they and how do you fit fascias and soffits

What is a Fascia?

A fascia is a long, straight board that runs along the lower edge of the roof, directly under the roof. They are primarily used to support the bottom roof tiles to hold them in place. This protects the ends of the rafters from absorbing water and causing water damage.

The fascia boards are also used as a base for the guttering to be mounted on. Due to this, the fascia must be strong so it can withstand strong winds and poor weather conditions. Fitting the fascia properly is essential to protect your roof from damage. 

Facias and soffits on a house

What is a soffit?

A soffit is fitted underneath the fascia to encase the rafters and further protect them from the rain. While they do not need to be as strong as the fascias, soffit boards should still be accurately fitted to prevent water damage to the rafters.

The soffits are also crucial for keeping birds and rodents out of your roof space. If there is a gap under the fascia, the unwanted visitors will enter through it and nest, not only causing an infestation but also potentially damaging your roof.

Choosing your Fascias and Soffits

When choosing your fascia and soffit boards, there are lots of material options. Traditionally, timber was used and while it may look more appealing, wood comes with a wealth of maintenance issues. From water damage to more frequent repainting, using wooden fascias and soffits is likely to end up more expensive in the long run.

Normally, uPVC is the material of choice as it is easy to install, durable and looks appealing. It is important to remember to tightly seal uPVC boards to keep them waterproof. Other materials, such as aluminium, can be used however tend to be less popular.

Housing standards require your roof area to be ventilated. This prevents your timber rafters from rotting and collapsing. Ventilation holes can be located on the fascias or soffits however soffit ventilation is more common as it is less visible from the ground.

Maintaining/cleaning Fascia

Installing your Fascias and Soffits

While many people choose to hire a contractor to fit their fascias and soffits, some decide to take on the job themselves. Whether you want to do it yourself or just know what your contractor is up to, we have put together this handy guide to help you out.

As always when working on your roof, it is a good idea to choose a dry, warm day to ensure no water gets into your roof space and causes damage.

Another important factor to consider is how you will access the fascias and soffits. As they are located under the roof itself, you cannot access them from on top of the roof. It is recommended that you use scaffolding to access the area as is it sturdier than using a ladder.

The boards you are working with tend to be long and difficult to carry and hold down on your own. If possible, find someone you trust to help you with the job to make it a lot easier.

Now you have chosen a sunny day, constructed your scaffolding and decided on your DIY partner, you are ready to start installing your fascias and soffits.


  • Soffit boards
  • Fascia boards
  • Hangers
  • Joint trim
  • Drill
  • 65mm plastic headed nails
  • 40mm plastic headed pins
  • Pencil
  • String
  • Measuring tape

Step-by-step guide

  1. First you should push back the bottom 2 layers of tiles to clear the working area and make the job easier. If you are replacing your fascias and soffits, it is important to check your rafters for decay or damage before you install the new ones. Also, if you notice the felt is damaged or has dropped back, fix this back into place before you start any work.
  2. Fix a piece of thick PVC board (also known as a hanger) at each rafter foot to act as a guide of where to place the fascia and soffits. It is a good idea to start with the two end hangers and connect them with a piece of string to ensure you don’t go off-track half way along. The maximum distance between hangers should be 600mm for white fixings and 400mm for coloured fixings.
  3. Fixing the soffit board:
    1. Start by placing the soffit under the hangers allowing 8mm gaps between each board for expansion.
    2. Next, secure the boards with 40mm plastic headed pins onto each hanger. This will ensure the soffit can withstand heavy weights and poor weather conditions.
    3. Finally add the soffit joint trim between each board to connect them and ensure they are secured.
Fixing soffits board
  1. Fixing the fascia board:
  2. Start by marking out 2 parallel lines along the protective film of the board where the nails will go at each rafter foot.
  3. Place the board along the hangers and drill into place, using the 60mm plastic headed nails. Start by partially drilling in the nails so you can easily remove the protective film. Once the film is removed, finish drilling in the nails.
  4. Between sections of fascia, fix the joint trim in by screwing it onto one of the boards, remembering to leave and 8mm expansion gap.
Fixing fascia board
  1. When fitting the end boards, make sure they are cut to size to keep the roof looking neat.
  2. Once you have fitted the fascias and soffits, you can now attach the box end, bargeboard and guttering to complete the roofline. This step ensures the roof looks finished and tidy.

Can Fascias and Soffits be used for all roof types?

Fascias and soffits not only improve the look of your roof, they also protect your roof from pests and water damage. For this reason, it is very important to have a form of protection at the end of your roof.

Most roof types are suited to fascia and soffit boards however some may be more complex than others. If your roofline is flat along the bottom of the rafters, the installation will be simple and you can use the above steps to guide you.

If your roof line is uneven or has multiple angles, you will have to consider this when measuring out your fascia and soffit boards as it will not be as simple as a straight line. If you think your roofline is complex, seek advice from a contractor before you start the project.

Now you have your guide on how to install your soffits and fascias, go ahead and share your photos with us on our Facebook page.