Glass roof systems with perfect air and waterproofing 

Airtight building is inextricably linked to sustainable building and stands for the whole set of regulations, calculations, systems and implementation methods, with the aim of closing air leaks in the building envelope. "Limiting air permeability is essential for keeping heat inside, saving energy, improving our comfort and preventing moisture, drafts and noise complaints," says Jan-Willem Hermans, Technical Manager at Kingspan Light + Air. "Our glass roof systems naturally go along with this and are constantly being developed, with an eye for the total insulation value of glass, rods and connections."

"Even if you select the best glass roof system with the best glazing: if the connections between the curb and the flat roof are not properly sealed, the complete thermal insulation is negated," Hermans illustrates. "Kingspan Light + Air overcomes these problems using EPDM seals that guarantee excellent air and water tightness. A strip of insulating material then ensures that no cold air can come up against the interior profile." 

Good and seamless connection

A major advantage of the EPDM seals over a compriband, for example, is their size, says Hermans. "The continuous seals can be laid more neatly over the upstands, ensuring a good and seamless connection. In addition, the air and water tightness of the EPDM material is better."

Efficient water drainage

"Our cover strips are of high quality," Hermans emphasizes. "Still, they cannot guarantee 100% waterproofing. A minimal amount of water will always infiltrate the rod system. However, a special design ensures that this water is drained out efficiently and through the aquifer channel in the head of the rod. In doing so, the aquifer channel serves as a kind of spout."

Improved trapping

An important development within Kingspan Light + Air's glass roof systems relates to clamping. "In glass roof systems, the glass pane is mounted on one side of the profile, while a closed panel is fitted on the other side," Hermans says. "This panel should be the same thickness as the pane, but in practice is often thinner. A hard plastic block absorbs this difference and also ensures less heat passage through the profile. The addition of a foam rubber in the glass seam also contributes significantly to this."

Vacuum glass with a constant Ug value

The insulation value (U-value) of a glass roof system is determined by the U-value of the glass (Ug-value), the U-value of the rod (Uf-value) and the heat loss through the spacers of the insulating pane (Ψ-value), says Hermans. "A challenge here is that a strict European product standard (CE standard) for glass roofs is lacking. Moreover, the slope of the double or triple glass affects the Ug value. Clients need to be aware of this so that apples to apples can be compared." Currently, Kingspan Light + Air is developing a system with a very good Ug-value, which does remain the same in every position and which allows a Uw-value of 0.5 in a glass roof system.

At the forefront of regulation

Recently, Kingspan Light + Air successfully tested the fly-fire resistance of its glass roof system, Hermans says. "As an organization, we hold the VMRG Hallmark. The VMRG is working at the European level to extend the standard for curtain walls to glass roof systems. In anticipation of this, we have already carried out all relevant tests, in accordance with the National Assessment Guideline for the KOMO® Attest for rooflights and skylights (BRL 0105). From wind and water tightness to wind resistance, U-value of the rod (Uf-value), sound insulation and fly fire resistance. This puts us at the forefront of the market and guarantees the quality of our glass roof systems." All test reports are available upon request.