Mardome Trade Polycarbonate Rooflight Specification
Mardome Trade Polycarbonate Rooflights come in a wide range of variations to suit any specification, choosing from different kerbs to dome shape, colour and glazing options, see below details about each variant to help you choose the right rooflight for you.
Please note that restrictions on opening units apply due to wind loading and weight, and powered opening rooflights are not suitable for use in conditions at risk of high humidity (e.g. domestic bathrooms).
Rooflight Glazing Options
The Mardome Trade range of rooflights can be made in different glazing types, each glazing type achieves different U-Values for what your want to achieve for your building.
Thermal transmittance of rooflights is assessed in the horizontal plane for compliance with Part L of building regulations. Mardome Trade rooflights have been assessed using the methodology in EN 1873:2014 and in accordance with NARM NTD2. Thermal transmittance is defined as a Urc value for a rooflight with combined PVC kerb and a Ur value for a rooflight fitted to a builders upstand. Mardome Trade rooflights with triple skin, quad skin, dome over glass or dome over structured glazing have a better thermal transmittance than the limiting value in Part L of 2.2 W/m2K. The thermal transmittance values (assessed horizontally) are shown below.
Mardome Trade (triple skin and better insulated variants) are designed for optimal thermal performance and resistance to condensation. This provides full insulation across the whole width of the rooflight (including the fixing flange), eliminating any cold spots associated with traditional methods of dome rooflight construction.
Dome Shape
The Trade Polycarbonate rooflight range can be made in 2 different shapes, either dome or pyramid as per the below.
Dome Tint
Mardome Trade Polycarbonate Rooflights can be made in different tints (Clear, Opal or Patterened/Textured) to suit the application you require. Each different tint will provide a different level of light transmission.
Rooflight Kerb
Rooflights can be supplied to fit an pre-exsisting structual, insulated upstand, or alternativly they can be supplied with a 150mm or 300mm uPVC kerb where no pre-esisiting structual insulated upstand is present. When fitting to a pre-exsisting structural insulated upstand, unventilated trade rooflights can be fitted directly, whereas ventilated or opening rooflights are supplied with a direct fix kerb.
No Kerb - Fixed, Unventilated Rooflight to Fit Pre-Exsisiting Structural Insulated Upstand
Direct Fix Kerb - Ventilated/Opening Rooflight To Fit Pre-Exsisiting Structural Insulated Upstand, incorperates ventilation and/or opening equipment.
150mm uPVC Kerb - To fit structures at roof surface level, with no pre-esisiting structural insulated upstand
300mm uPVC Kerb - To typically fit below roof surface level for insutation, with no pre-esisting structural insulated upstand.
Rooflight Ventilation
Ventilation is key to helping your building breath, reducing humidity and the risk of condensation and should be considered when installng a rooflight, espcially in areas of high humidity. Mardome Trade polycarbonate rooflights can be made with or without ventilation. A rooflight with ventilation can be made in 3 different types, being trickle ventilation (Hit and Miss) commonly found on PVCu doors and windows, automatic humidity controlled trickle ventilation or a high extraction powervent ventilation fan.
For further details or if you have any other questions please contact us on 03302 230 267, via email
[email protected] or via live chat and we will be happy to help you further.
