At Trade Access Panels we are often asked questions regarding building regulations for skylights and other questions in relation to Flat Glass Rooflights. We have tried to jot down the most frequently asked questions in an effort to assist you however if you should require any further information or assistance then please do not hesitate to get in touch with our sales team accordingly.

Building regulations for skylights Infographic

Q) How quickly can I get my Flat Glass Rooflight delivered?

A) This depends on the spec of Rooflight ordered. If you go with a stock size Flat Glass Rooflight, then it would be delivered within 2-3 working days (opening Flat Glass Rooflight in a stock size would be 5-7 working days from Order). If you decided to go with a bespoke Rooflight then it would usually be delivered to your site within 12-14 working days from receipt of order and confirmation of layout drawing. Exact lead-time would be confirmed at the point of Quotation and Order.

Q) What Guarantee is provided for my Rooflight?

A) Rooflights are supplied with a 10 year manufacturers Guarantee.

Q) How long will it take for me to have my Rooflight fitted?

A) This is a tricky one to answer, and is dependent on who is fitting the Rooflight. We would always suggest that you seek professional advice regarding the installation of a Rooflight to avoid leakages and/or injury when working at height. Roughly, it would on average take around half a day per Rooflight/Skylight to complete the exterior portion of the installation plus around another half a day for the interior portion of the installation, which would include the drywall/plastering and painting/finishing. The type of ceiling you have within your home (for example either vaulted or flat) would also affect the length of time it takes to complete the interior portion of the Rooflight/Skylight installation.

Q) Do you do supply and fit?

A) We do not provide an installation service, however any local competent and experienced Roofer or Builder should be more than capable of fitting the Rooflight for you.

Q) How much does delivery cost?

A) Delivery to Mainland UK is FREE of charge during normal weekday working hours. Due to the weight and size of a Rooflight, please ensure that there is adequate access to site for the large delivery vehicles. If alternative smaller transport is required, then this may be at an additional cost.

Q) What is a U-value?

A) The U-value or thermal transmittance is the rate of transfer of heat through a structure (which can be a single material or a composite), divided by the difference in temperature across that structure. U-values are measured in watts per square metre per degree Kelvin (W/m²K). Briefly, the better-insulated a structure is, the lower the U-value will be.

Find out more about the U-Value of Rooflights >>

Q) Do I need Planning Permission to fit a Roof Light?

A) According to the building regulations for skylights, when it comes to installing Rooflights or skylights as a domestic property, as a general rule there is not a need to apply for Planning Permission however if in doubt expert advice must be sought.

Q) I can see you sell Rooflights with and without a Kerb. What is a Kerb?

A) A kerb or Upstand is used to prevent the Rooflight from coming into contact with actual roof surface which is required for most Building Regulations. The kerb/upstand should be a minimum of 150mm to ensure your unit is fully weatherproofed/watertight. Each spec of Rooflight may require a slightly different Kerb if building the same on site so please ask if in doubt.

Q) What do I need to measure when checking the size requirement?

A) This depends on whether you are building a timber kerb or are using the uPVC 150mm upstand supplied.

If you are building a timber Kerb then this needs to be a minimum 150mm high and the size of the rooflight you order is the external upstand dimension ie a 600x600mm glass rooflight will require a hole cut of 450x450mm (75mm wide each side timber kerb gives you an external size of 600x600mm).

If you are using the Upvc kerb supplied the hole you cut in the roof is the size you order ie a 600x600mm glass rooflight you cut a hole 600x600mm. See the rooflight measurement drawings >>

Q) I want my Flat Glass Rooflight to open for ventilation. Is this possible?

A) We offer Mardome Opening Flat Roof Window options which can open electrically or manually . These can be provided with remote controls and rain sensors as an extra over option. We also offer a manual operated option from Mardome however we would recommend that this is only used for a Rooflight size up to 1200x1200mm due to the size/weight of the Rooflight.

Q) I am after an unusual colour of frame for my Rooflight, is that possible?

A) We can provide Flat Glass Rooflights with other RAL colour frames, however the lead-time and costs will be higher than the standard stock options.

Q) What are the benefits of a Flat Glass Rooflight?

A) Skylights and Rooflights can completely change a room for the better. They soak a room in the underutilised natural resource of daylight, making it brighter. Skylights and Rooflights can also provide ventilation into a room, which can be very beneficial when fitted in a kitchen or bathroom environment. They can also add value to your property.

Q) What is cold bridging?

A) Cold bridging is when condensation forms on the inside of the Rooflight framework. This most commonly occurs when the Rooflight has been installed within a high humidity room such as a bathroom or kitchen. We can offer Rooflights with Trickle Vents within the kerb/upstand or manual or electric opening to help eliminate this issue (please ask in in doubt).

Q) I require an unusual size Rooflight. Do you provide these?

A) We can provide Glass Rooflights in almost any size. One of the latest additions to our range, the Mardome Modular Glass Link option provides Rooflights with a maximum span of 3.8m and unlimited length and can be installed at a 2-35 degree (span), 0-15 degree (length) pitch making them the perfect choice for many projects.

Q) My flat roof has a slight pitch can I fit a flat glass rooflight?

A) Yes. They are suitable for mounting at pitches of 2–15°.

The Flat Glass Rooflights are ‘flat’ and so are the kerbs. The pitch of 2° should be on your roof already to enable rain water to run off. This is not always the case however and if you should have a ballasted roof (i.e. stones, tiled or green) then you will need to ensure that the roof openings are pitched accordingly.