Flat Roof Skylights

Time to test your joinery!

Your skylight needs a minimum 1 in 40 slope, or 1.5 degrees.

You may naturally have a slope on your flat roof, contributing partly to the fall already. 

Ideally, the direction of water run-off on your skylight should go across the shortest run, or width, & towards your gutter edge - thus reducing pooling at the highest side of your skylight.

Baring in mind your total kerb height must reach 150mm, with or without the optional supplied 70mmx80mm rebated kerb - the gradient can be achieved with 'firings' or chamfered timber. For example, 2'' to 0'' firings running across the width. you will then need to pack the highest side by 2'' across the full run, so there is no cavity & even weight distribution.

• How efficient are the skylights?
  The triple-glazed glass for the Flat Roof Skylight Range has a U-Value of just 0.6 W/m2K. This impressive thermal efficiency is compliant with building control standards.
• How safe are the skylights?
  The triple glazed unit consists of 6mm toughened self-cleaning glass, a 16mm warm edge spacer unit, filled with Argon & a 4mm toughened, clear, soft coat e glass. These combine to make a very safe and durable skylight. Safety in handling and installation, including the correct use of PPE should always be prioritised.
• How should I handle the skylights?
  Firstly, you should calculate the weight (grams) of the glass by using the method in an FAQ down below. You should then make a reasonable judgement about the number of personal required to safely lift the glass up and into position. Safety boots, safety gloves, steel toecaps and safety goggles are a must. Depending on the size and weight, you may need to consider the mechanical aid of something such as genie lift, cherry picker or crane – utilising safe packaging and support of the glass during transit. Some installers consider using various suction cups to safely transport the glass. Ensure trained operators only on lifting devices and experience individuals on using the correct suction cups.
• Can the skylight be damaged?
  Yes, although the glass is triple glazed, durable and toughened. There is potential for damage including a scratch or break. When you are transporting your glass, use correct support packaging and loading the glass on any corners. Spread the weight as much as possible during handling.
• Can you offer a bespoke size?
  Yes, we can supply bespoke skylights, subject to the size required. These can take longer to manufacture (a minimum of 10 working days) so please allow ample time if considering this option. We would require your internal structural opening size and notice if a different rebated timber kerb is required, other than the standard provided. Note bespoke sizes will incur an additional cost compared to similar ‘off-the-shelf’ sizes.
• Do you sell or fit blinds for the skylights?
  Unfortunately, we don’t sell blinds. These will need to be sourced from your local blind supplier or online. If in the Lincolnshire area, we can put you in touch with a reputable Thomas Sanderson Surveyor, a premium blinds manufacturer.
• Do you offer an installation service
  Typically we do not offer an installation service. However, if you are located near our business location in Lincolnshire: Depending on the job requirements, our Lincs Group LTD team with over 30 years experience may be able to provide this service. Please note, our team only works with EPDM rubber flashing when installing these on flat roofs. A clear and handy installation guide is provided for a self installation service however, and we’re happy to answer any of your questions in regard to installation of the rooflights.
• Can I collect my skylight?
  Unfortunately collections are currently unavailable.
• Do you do next day delivery on skylights?
  At the moment, we do not offer next day deliveries. Our current estimated delivery time is 2-3 working days, depending on your location in the UK & the size of your skylight. We will update you within reasonable time of the actual day of delivery, so you have time to arrange someone to receive and sign the delivery.
• What is the delivery time of the skylights?
  Depending on your location, we aim to deliver all of our orders between 2-3 working days (excluding the large category of skylights). Check out our delivery zone charge and ETA delivery table for more info.
• What warranty is available on the skylights?
  All of the Flat Roof Skylights come with a 20-year manufacturer's warranty for the sealed unit only.
• What is the weight of the glass?
  To weight of each glass unit is available on your order or each product description. If for some reason you can’t locate this: Calculate the weight of the glass: First, calculate the external size of the glass by adding 200mm the width and length of your internal measurement. (a 600 x 600 mm skylight becomes 800 x 800mm). Then multiply these external measurements x 0.037 to get the weight in grams. See below example: A 600mm x 600mm skylight (internal measurement) has an external measure of 800mm x 800mm Therefore; 800 x 800 (640,000) x 0.037 = 23,680g. (23.68kg).
• What is the external size of the glass?
  All of our glass is made in the same way so to get the external measurement just add 200mm to the width and length. For example, a 1000mm x 1000mm externally would be 1200mm x 1200mm.
• How is the skylight secured to the timber kerb?
  You must use a high-quality low modulus silicone adhesive to bond the glass to the timber kerb. The silicon is applied to both the top of the kerb and the rebated section of the kerb, with the silicon thickness being uneven to create an even ‘bed’. We advise CT1 as a prime example. This will bond the glass to the kerb as well as create a watertight seal.
• What size upstand or kerb do I need?
  If you are using the optional timber rebated kerbs provided with your skylight, see below: Your own upstand needs to be 70mm x 80mm (width x height). The rebated timber kerb supplied then fixes on top of your kerb, mechanically fixed with no proud fixings (important). If you are not using our kerb and are creating your own, it is best to refer to our fitting guide ‘Flat Roof Skylight Guide when using your own Kerb'.
• What size is the optional timber kerb supplied?
  Our timber kerb is 70mm x 70mm, with the top section being partially rebated for the glass to sit in. You will need your own timber kerb for this to stop on and mechanically secure to. The minimum total kerb height is 150mm from the decking/joists and the top of the timber kerb.
• What do the sizes you quote represent?
  All our advertised sizes are internal structural opening sizes. These are also known as joist to joist (internally) or reveal measurements.
• Are the rooflights safe to walk on?
  No, though all of our skylights are made with toughened glass throughout, it is not safe to walk on.
• How do I place a rooflight order?
  Ordering a rooflight with us couldn’t be simpler. All you need to do is select the rooflight product, size and quantity you want before selecting ‘buy now’. Our secure payment gateway will then walk you through payment and delivery options.
• Do the rooflights open?
  No, all skylights supplied are fixed and non-opening. For Flat Roof Skylights, this is the best way to eliminate the change of potential leaks (when installed correctly), and offer a highly competitive price.
• How should I maintain my skylights?
  The Flat Roof Skylights are made with self-cleaning glass, which does reduce the maintenance required. However, to keep your skylight clean and fresh, we advise, if safe to do so, to manually clean them quarterly. Harsh chemicals and abrasive tools are not required. A cloth and warm soapy water or glass cleaner is your best option.
• Do I need a slope or fall on my skylight?
  Yes, you need a minimum gradient of 1 in 40. This can also be calculated as 40mm for every 1000mm run of your skylight; or 1.5 degress. This fall run will usually be on your shortest edge and towards the gutter edge of your roof. Alternatively, there is a maximum pitch. We do not advise installing over a 22 degree pitch due to potential wind uplift. As a general rule, we advise a 5 degree slope on your glass to stop water from pooling on your glass.