The Options
So you moved into a property X number of years ago that has one
or more roof windows - and now they need
replacing. What are your options? Follow this step - by -step guide
to save yourself the stress of finding out.
Step 1: Finding out the particulars 
Gather as much information as you can about your roof window to
give yourself a head start. Inspect the window for details of
manufacturer, brand and size. You should be able to find a data
plate somewhere along the sash of the window (viewable when opened)
with manufacturer's codes. Take a note of these for later. You
might be able to decipher the codes on the manufacturer's website
to give you a size and glazing type, or you can contact the
company's customer services for help. A roof window merchant
company might also be able to help you with this.
If you can't find a data plate or brand details, or your
skylight is very old and does not have these, don't worry.
Contemporary roof windows are sold by their external frame size, so
this is the only piece of information you'll strictly need to know.
Measure the inside frame and add on several centimetres to give you
a general idea, or better yet measure the window frame from the
outside if it is safe to do so or get a roofer or builder to do it
for you.
Option 1: Replace the pane
This is only an option if the existing roof window frame is in
good condition, and you know the make and model. Most roof window
brands sell replacement glazing panes for their windows, so the
first port of call would be to contact the company by phone or
email or to browse their website to find the correct product. You
will usually have the option of purchasing glazing like-for-like or
upgrading to a better glazing spec, e.g. from standard double
glazing to safety glazing or enhanced noise reduction, or even
triple glazed.
As most brands do no sell to the public directly, you will need
to go through a merchant, such as a local builder's merchant, or
search for roof window retailers online. The
customer service staff should be able to help you if you're not
sure what you're looking for. Remember to order the correct size -
this is where the codes you copied down earlier will come in
handy!
Option 2: Like for like
If your entire unit is worse for wear, you are best off opting
for a whole new roof window. You can replace your window
like-for-like if the unit is still in production, or with an
equivalent sized roof window if it is not or you decide to opt for
a different brand. Remember, roof window sizes generally go by the
external frame size. If you are in any doubt regarding which of two
sizes is closest to your existing skylight, you are best opting for
the larger size, as this will be easier to fit (it is a lot less
work to cut out a larger hole in a roof than to build up a hole to
make it smaller). If you are opting for a larger size, it is worth
checking with your roofer or builder that your roofing structure is
able to accommodate it before you make the purchase.
Option 3: Upgrade 
If you have to replace your roof light, this is an excellent
opportunity to upgrade. Below are some examples of roof window
features that you might want to consider when browsing for a
replacement.
Window frame:If you have a pine window frame, you might want to
consider upgrading to polyurethane coated white. The white is
moisture resistant (perfect for kitchens and bathrooms), easier to
maintain and provides a more contemporary finish.
Opening style:Most older style roof windows work on a central
pivot, opening into the room itself, which can obstruct views. Top
hung roof windows are also available - these cost a little more but
have the advantage of opening all the way outwards from a top
hinge, offering the best views and zero obstruction.
Automatic operation:Electric and solar powered roof windows are
readily available. Common features include remote control operation
- perfect when out of reach - and automatic rain sensors which shut
the windows upon the slightest detection of precipitation.
Enhanced glazing:You can get laminated safety glass - ideal for
windows above head height - noise reduction glazing to cut out
external sounds, and triple glazing for the highest levels of
energy efficiency.
Option 4: Total overhaul
If you really want to make the best of a renovation opportunity,
you need to think one step further than an ordinary roof window.
You could look into creating a roof terrace, which is a roof window
system that opens out as a door, from which a small railed platform
extends from your roof. Another option is a roof window balcony system, which acts
very much in effect like a pop-up balcony. The windows open
outwards in a balcony style offering extended space and views, but
fold back in line with the roof when not needed.
After all - as the chocolate advert says, why have cotton when
you can have silk? We're sure this applies to houses too.