Velux Windows in Harpenden

Velux windows are a great way to add lots of light to your loft space. Velux is actually the name of a brand of roof window – not to be confused with roof lights, which are usually installed on flat roofs, or skylights, which are normally used to add natural light into a room without being able to open it. Roof windows open like regular windows and are fitted within your roof. But how much are Velux windows? Whether you choose a Velux window or another brand of roof window, they’re not cheap. Since they require special installation, including cutting roof timbers and replacing them to keep the structure strong enough, they take longer to install than a normal double glazed window. It can take up to a day to install a large Velux window, and it could set you back anywhere between £1,600 and £2,000. If you only need a small roof window in an area like a bathroom, you can expect to pay up to £1,300 for it to be fitted. Usually, there won’t be any need for scaffolding or towers because Velux windows are designed to be installed from the inside of your home. However, it’s worth setting aside an additional £500 in your budget in case unexpected problems occur and an installer needs to get on your roof to finish fitting the window. All of these prices are based on a standard roof window without any additional features. If you want to be able to control your windows with an electric switch or remote, this could set you back as much as an additional £400. For extra-low energy glass, you can expect to pay up to £200 more.

In general, no – you don’t need planning permission for a Velux window. The Planning Portal says that you don’t need to apply for planning permission to install a roof window if the following conditions are met:

• A roof window must not protrude more than 150 millimetres above the existing roof plane
No roof window or any other alteration can be higher than the highest part of the roof or stand out above the roof ridge
• Side-facing windows must have obscure glazing to protect privacy of neighbours and, if they open, they must be 1.7 metres above the floor of the room in which they are installed

You don’t need to apply for planning permission for a roof window because they are covered under permitted development rights. However, if you’re a leaseholder or you live in a building where your local authority has made an Article 4 Direction, you will have to apply. Usually, an Article 4 Direction is made when you live in a conservation area where any external home improvements could affect the character and look of the area. Luckily, there are special Velux windows that are designed to be more likely to be accepted by your local planning authority. They’re called conservation windows and, although there’s still no guarantee that they will be accepted, they are designed to look more traditional. Even if you don’t need planning permission for your roof window, you still need to follow any relevant building regulations for your local authority. The most important parts for Velux windows are section J and section L of building regulations, which refer to energy efficiency, thermal insulation and fire protection.

If you’ve never had Velux windows before, you might be wondering how to open them. If you’ve got very high ceilings and your roof windows are set high up in the pitch of the roof, you might not even be able to reach them. So how do you open them in this case?

When Velux windows are installed so high that they’re out of reach, the installers will often recommend that they install an electric switch for you to open and close your windows. They often come with a rain sensor, so you don’t need to rush up to the top of the house if there’s a sudden downpour – they will close automatically. You can also choose to have a remote so you can open and close your roof windows wherever you are in the room.

If you don’t have an electric switch, but you still can’t reach to open and close your Velux windows, you should be supplied with a telescopic pole when they’re installed. If you weren’t or you’ve moved into a home with roof windows and there isn’t one, you can buy them online. They have a hook on the end and can be extended to the correct length so you can hook it over the handle of the window and pull or push to open it.

If you’ve got a top-hung Velux window that can also be opened in a centre-pivot position, it’s easy to switch between the two. Simply ensure the window is completely closed before you start, then open the handle up – but don’t push it out. Then pull the vent bar down until the sash is rotated 180 degrees. Then secure the position by sliding the barrel bolts into the holes at either side of the bottom of the frame. Easy!

Fitting a Velux window into a slate roof is very similar to the way you’d install it in other roof types. All roof windows, whether a Velux-branded one or not, will come with detailed instructions for you to follow if you want to have a go at fitting it yourself. But here are some brief instructions to give you an idea of what’s involved in installing a Velux window into a slate roof:

1. After you’ve removed the Velux window from its packaging, remove the sash (the part that opens) from the frame, according to the manufacturer’s instructions.
2. Next, you need to prepare the opening for the window. You can often cut through the felt, remove one of the battens from under a slate, then slide all the slate tiles into the roof space. You should then make the cut 40-60mm wider than the window, cutting away roof timbers then replacing them with more around the opening to strengthen it.
3. The roof window’s bottom brackets need to be installed on one of the existing battens for the slate roof. One of the slate courses should line up 105mm below the top edge of the batten you use.
4. Then, measure from the top edge of the batten upwards to the height of the window plus 45mm. This is where the top installation batten should be installed, with an overhang of 100mm on each side.
5. Remove the course of slates below the window, trim any excess felt and fold it over the surrounding timber. This helps with waterproofing.
6. Add the insulation collar according to the Velux window manufacturer’s instructions.
7. Place the frame in the opening, adding the brackets according to the instructions. You’ll find that lots of roof windows have pre-drilled holes to make it easy for you.
8. Replace the sash and line up the hinges. Take a look at the opening at the bottom between the sash and the frame – it should be even along the entire width. Remove the sash again to fix the upper brackets according to instructions.
9. Add the underfelt collar for your roof window as instructed by the manufacturer, then replace any slates at the bottom. You might need to cut them to size.
10. Next, add the flashing according to the instructions, along with any parts that are not yet attached, including the hood section and top flashing piece.
11. Replace all the slates around the window, allowing 60-100mm of space between the course of slates above the window and the top of the window to allow for rainwater drainage. Then replace the sash into the frame again.
12. Add the vapour barrier on the inside of the window using the screws provided, then tape it to the existing vapour barrier to prevent moisture from reaching your roof structure.

And that’s it! If you think that sounds a bit complicated, ask a roofer or window installer to fit your roof window into a slate roof for you. You’ll get a better finish and you can be sure that you won’t get any leaks from a botched installation.