Rooflights for Irish Buildings: Types, Uses and How to Choose
Rooflights — also called roof panels or roof windows — are a simple and cost-effective way to bring natural daylight into agricultural, commercial and domestic buildings. Replacing even a small number of opaque roof sheets with clear or translucent rooflights can dramatically improve the working environment and reduce dependence on artificial lighting throughout the day.
At O'Connor Roofing Supplies, we stock a wide range of rooflights to suit all the main roof sheeting profiles used across Ireland.
Types of Rooflights Available
Clear Polycarbonate Rooflights
Polycarbonate rooflights are the most popular choice for agricultural and commercial buildings. They are available in a wide range of profiles to match standard corrugated, box profile and Big 6 sheeting. Key properties include:
- High light transmission — typically 80–90% visible light transmission for clear variants
- Impact resistant — significantly stronger than glass and GRP
- Lightweight — easy to handle and install on site
- UV stabilised — resistant to yellowing and degradation over time
- Available in clear, opal (diffused light) and tinted variants
Standard polycarbonate rooflights are a single-skin product — they do not provide significant thermal insulation.
Kingspan Insulated Polycarbonate Rooflights
For buildings where insulation performance must be maintained even at the rooflight positions, Kingspan insulated polycarbonate rooflights are the premium solution. These are designed to be used with Kingspan KS1000RW insulated roof panels, sitting flush in the panel roofline for a weathertight, thermally efficient finish.
Benefits include:
- Maintains thermal continuity of the insulated roof
- Excellent U-value compared to single-skin rooflights
- Non-drip design prevents condensation issues
- Available in lengths from 1.8m to 8m, cut to requirement
GRP Rooflights (Super 4)
GRP (glass-reinforced plastic) rooflights, including the Super 4 profile, are a robust option for agricultural and industrial use. They are available in corrugated profiles and offer good long-term durability in farm environments. The Super 4 GRP rooflight from O'Connor Roofing is 3.05m long x 815mm wide (762mm cover width) and suitable for agricultural and industrial applications.
Big 6 Clear Rooflights
Big 6 rooflights are designed to match the Big 6 corrugated profile commonly found on older agricultural and industrial buildings. If you are re-roofing a building with Big 6 sheeting, or need to add rooflights to an existing Big 6 roof, these are the correct product to use.
How Many Rooflights Do You Need?
A common rule of thumb for agricultural buildings is to include one rooflight for every 10–15 linear metres of roof run, depending on the building use and natural light requirements. For buildings housing livestock, natural light is not just a comfort factor — it is an important consideration for animal welfare standards under current Irish and EU regulations.
For commercial buildings, your architect or building energy consultant will typically specify the rooflight area required to meet daylighting requirements under building regulations.
Matching Rooflights to Your Roof Profile
The most important thing when ordering rooflights is to match the correct profile to your roof sheeting. Using the wrong profile will result in gaps, leaks and a poor-quality finish. The main profiles available are:
- Corrugated (3-inch pitch sinusoidal) — the standard corrugated rooflight for most agricultural buildings
- Box profile — to match standard box profile sheeting
- Big 6 — for Big 6 profile sheeting found on older buildings
- Kingspan KS1000RW profile — for use with Kingspan insulated panel roofs
If you have an older or non-standard profile and are struggling to source a matching rooflight, O'Connor Roofing specialises in custom polycarbonate rooflights manufactured to match discontinued or unusual profiles. Bring us a sample, photograph or measurements and we will produce a match.
Frequently Asked Questions
How long do polycarbonate rooflights last?
A quality UV-stabilised polycarbonate rooflight will typically last 15–25 years before requiring replacement, depending on the grade of material, installation quality and local climate conditions. Cheaper unbranded polycarbonate can yellow and become brittle much sooner — always ask about the UV protection specification when purchasing.
Can I add rooflights to an existing corrugated roof?
Yes. As long as you can match the existing profile, rooflights can be added to an existing corrugated or box profile roof relatively straightforwardly. The rooflight is simply fitted in place of a standard sheet. O'Connor Roofing can supply rooflights cut to your existing sheet length.
What is the difference between clear and opal rooflights?
Clear rooflights allow maximum light transmission and you can see through them. Opal (milky white) rooflights diffuse the incoming light, reducing glare and creating a more even light distribution inside the building. Opal rooflights are often preferred for workshops and commercial spaces. Clear rooflights are more common in agricultural applications.
Order Rooflights from O'Connor Roofing
We stock a comprehensive range of rooflights to suit all standard profiles, with cut-to-length service and nationwide delivery. Contact our team to discuss your requirements.
Phone: 042 937 6314 | Email: info@oconnorroofing.ie
Rampark, Jenkinstown, Dundalk, Co. Louth, A91 XC94
