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Flat Roof & Conservatory Roofs

Adding Skylight To Existing Roof: The Essential Guide

adding-skylight-to-existing-roof

So you’re thinking about adding skylight to existing roof space? There are plenty of things you’ll need to consider before embarking on such a huge project – and we’ve put together a step-by-step guide to help you get the job done properly first time…

Prioritise Skylight Placement

You’ll need to think about the placement of your skylight before anything else-and with good reason.

Bear in mind that skylight placement will largely depend on your property’s rafter placement and having a space plan or blueprint to hand before you start is a good idea.

Installing Skylights: 6 Key Factors To Consider

You should always invest in quality when adding skylight to existing roof spaces. You’ll need to think about things like:

  • Water tightness
  • Soundproofing
  • Wind resistance
  • Energy efficiency
  • Ventilation
  • UV coatings

Unless you’re an expert carpenter, you should really hire professionals to install your new skylight, as they’ll come with all the safety gear and tools needed to get the job done to a high standard.

Installing a skylight yourself can not only be dangerous due to working at height, there are also plenty of things that could go wrong

For example, you could install a skylight on a South facing section of roof without considering ventilation or blinds to control the sunlight. Or you could fail to ensure your installation is structurally sound, damaging your property.

Let’s Get Started!

We promised a step-by-step guide to installing a skylight, so here goes:

For most installations you will need:

  • The skylight itself
  • 2 by 4s for the frame
  • Supplies for drywall and ceiling finishing
  • Nails
  • Roofing paper
  • Step and continuous flashing
  • Tools including a hammer, circular saw, snips, flat pry bar and a utility knife

adding-skylight-to-existing-roof

It’s always best to hire expert installers. Not only can they offer advice on the type of materials to use for your skylight, its location and other important things to consider – like the direction your proposed location faces – they can also ensure adding a skylight to your existing roof area is carried out quickly, efficiently and for an affordable price

Adding Skylight To Existing Roof: 5 Step Guide

Step 1: Cut and Frame the Opening

Working from the inside of the roof, drill a hole to mark the centre of the skylight, then cut the opening with your circular saw. One of the most complex, crucial parts comes next: framing the opening to ensure it is structurally sound.

For skylights with an attic below, this is even more complex, as you’ll need to cut and frame a hole in the ceiling of the room below the attic, framing a light shaft through the space.

Step 2: Cut the Roof Shingles

This should be done on all four sides of your skylight, around three inches from the opening.

Centre the skylight on the opening, and fix it in place with screws or nails

Step 3: Add the Underlay

Add an underlay to this by cutting 8” wide strips of roof paper which you’ll slip carefully under the shingles.

When doing this, down-roof pieces should overlap up-roof pieces to ensure water will be properly shed.

Step 4: Install Bottom and Step Flashing

To install the bottom and step flashing, sit the bottom flashing on top of the roof shingles, and attach it with flashing or roofing nails driven horizontally into the skylight. Then carefully slide the step flashing in, under the shingles.

It’s best to start at the bottom, working your way up. Each piece of step flashing should overlap another by around four inches; remember to attach these to the skylight itself, rather than the roof.

Final Step – Attach Solid Flashing

Finally, it’s time to install the pieces of solid flashing. These prevent water entering the space between the skylight and the step flashing.

First, attach the piece at the bottom, then the sides, and finally the top, slipping it carefully under the roofing. Once again, attach it to the skylight, not the roof.

Enlist The Help Of The Experts!

As you can see from the above guide, installing a skylight requires some advanced carpentry skills and knowledge. You’ll need specialist tools, and all the right materials; and even then, there are no guarantees that your skylight won’t leak or be structurally unsound if you have installed it yourself.

It’s always best to hire expert installers. Not only can they offer advice on the type of materials to use for your skylight, its location and other important things to consider – like the direction your proposed location faces – they can also ensure adding a skylight to your existing roof area is carried out quickly, efficiently and for an affordable price.

Our team has years of experience installing skylights for our customers, and we’re here to help. To find out more and get a quote for adding a skylight to your existing roof, just get in touch with us today, by calling 0800 1700 636, or by simply clicking the button below!