Mardome Reflex Roof Dome - Double Skin Polycarbonate
Product details
Mardome Reflex, double skin — glazing-only thermal upgrade for existing upstands
Two skins of Marlon FSX polycarbonate, co-extruded with UV protection to both faces. Overall U-value 1.94–2.66 W/m²K, 85% light transmission in clear.
The dome comes off once. While it is off, this is the only chance to improve the thermal performance of that opening without touching the upstand, the membrane or the roof finish, and the next chance after that is the next dome failure. Where the space below is heated, the double skin is the version that earns its money: it cuts heat loss through the opening and lifts the inner surface temperature, which is what stops a cold single skin dripping onto the floor in winter.
- Overall U-value 1.94–2.66 W/m²K, calculated to NARM Technical Document NTD02 — varies with size and specification, so confirm the figure for the size you are ordering
- Light transmission to DIN 5036: 85% clear, 78% patterned, 35% opal
- Fits the upstand that is already there — no roof opening work and no making good
- Ideal for refurbishment projects, suitable for roof pitches up to 15°
- Achieves Class B non-fragility to ACR[M]001 when new and fully installed in accordance with the manufacturer's installation guide
- Single skin, double and triple skin units available (separate product listings)
- Can be mechanically fixed to existing kerbs without a kerb adaptor
- Standard sizes from 450 x 450mm to 2400 x 1800mm, low rise dome or pyramid
- 70mm or 100mm wide flange (undrilled so you can put fixings exactly where needed)
- Supplied with fixing pack inc. a roll of adhesive, weathertight washers, fixings and caps
Single, double or triple — which one
All three fit the same upstand and install the same way. The difference is what you are paying for.
| Skins | Overall U-value (W/m²K) | Light transmission, clear | Use it when |
| Single | Not assessed | 90% | The space below is unheated — stores, plant rooms, garages, covered walkways |
| Double | 1.94 – 2.66 | 85% | The space below is heated and you want the opening to stop being a cold spot |
| Triple | 1.26 – 1.77 | 78% | Thermal performance is being assessed, or condensation has been a recurring problem |
If the roof void or room underneath is genuinely unheated, the single skin does the same daylighting job for less money and lets in more light. Buy that one instead.
What it does not do
Mardome Reflex replaces the glazing only. If the existing upstand is uninsulated, it stays uninsulated, and it will govern how the opening performs regardless of which dome sits on it. Worth checking before you specify a triple skin.
The published U-value is for the rooflight, calculated to NARM NTD02. It is not a figure for the finished opening on your building.
How to select the correct size roof light
Measure the outside edge to the outside edge of the upstand, any given size of the Reflex dome will fit up to 18mm bigger than the nominal dome size or:
60mm less for domes with a 70mm flange
120mm less for domes with a 100mm flange (100mm flange not available on some sizes)
See below
Example size compatibility
| Nominal dome size | Flange size | Smallest upstand measurement | Biggest upstand measurement |
| 900 x 900mm | 70mm | 840 x 840mm | 918 x 918mm |
| 900 x 900mm | 100mm | 780 x 780mm | 918 x 918mm |
If your upstand falls between two sizes, send us the measurement and we will confirm which dome fits before you order.
Mardome Reflex is a glazing only unit designed specifically for refurbishment projects where the glazing only needs to be replaced. The unit is supplied with a fixing kit including weathertight washers and cover plugs. Manufactured from Marlon FSX Longlife polycarbonate, this glazing unit is up to 200 times stronger than glass. The high resistance to breakage and adverse weather conditions means Mardome Reflex is very safe and reliable.
Light Transmission
| Tint | Lighting effect | Double skin, DIN 5036 |
| Clear | High visibility | 85% |
| Patterned | Privacy | 78% |
| Opal | Diffused light and solar control | 35% |
Composition
Polycarbonate is light weight and has an impact strength 200 times greater than glass which makes breakage very difficult.
Fire Rating
Building Regulations Approved Document B sets out the rules for fire safety of buildings, which can be met by achieving specific fire ratings to either British (BS476) or European (BS EN 13501) test standards.
Brett Martin Daylight Systems Mardome Reflex Rooflights achieve Class B s1, d0 to BS EN 13501: Part 1. Building Regulations state they can be regarded as Broof (t4).
Safety Requirements/ CDM Regulations
Reflex rooflights achieve Class B non-fragility to ACR[M]001 when new and fully installed in accordance with the manufacturer's installation guide.
Foot traffic on all rooflights should always be avoided; impacts such as foot traffic or a falling person may cause damage which may necessitate rooflight replacement.
Guaranteed for 10 Years
Mardome Reflex Rooflights are designed to remain fit for purpose in normal industrial conditions for a period of 20 years (Guaranteed for 10). They will not become perforated, lose significant structural integrity or distort to the extent of losing weather-tightness. In addition the polycarbonate used is guaranteed against loss of daylight transmission, discolouration or loss of impact strength for 10 years.
Quality
Mardome Rooflights are designed and manufactured under an ISO9001 approved quality system.
BBA Approval - Full BBA approval under 06/4385
Returns
Please note, due to the nature of this product our standard returns policy does not apply. Returns will be subject to a restocking fee. The product must be returned in the condition it was dispatched in (i.e. in saleable condition in its original packaging).
Specification
- Glazing
- Double Skin
- Tested to
- Class B non-fragility to ACR[M]001
- Material
- Polycarbonate