Provide a sheet metal roof with double insulation

A sheet metal roof is weatherproof and weatherproof and, if properly installed, does not let any precipitation through. It doesn't weigh much and is very durable. However, all buildings apart from unheated sheds far away from every residential building cannot do without insulation. Sound as well as heat and cold must be insulated through.

Sheet metal even requires reinforced insulation

A sheet metal roof has no insulation properties worth mentioning and the material must be understood more as a waterproof roof membrane. In addition, the specific physical properties of metal lead to extreme heating and enormous cooling.

If you choose a sheet metal roof instead of a tiled roof, the amount of insulation required is greater, as the sheet metal only contributes its insulating properties indirectly, for example through the surrounding air cushions. However, compared to brick, sheet metal leaves so much more space due to the difference in material thickness that very similar overall insulation values result from the same roofing thickness.

Insulate cold, heat and sound

A tin roof needs sound insulation in order to keep the noise level in rain and wind within acceptable limits. The insulation against sound cannot be separated from the insulation against heat loss and the ingress of cold.

Some insulation measures against noise have a direct influence on the thermal insulation. Insulate the structurally necessary rear ventilation against condensation and the air cushions that arise in it. At the same time, space is created here that sound can use to spread.

Direct contact between sheet metal and insulation material creates problems

The substructure of a sheet metal roof should always be rear-ventilated with a gap between sheet metal and insulation material. So-called sandwich panels and thermal tile elements, in which the sheet metal is attached directly to the insulation layer, cause problems sooner or later in almost every type of construction.

This fact should also be taken into account when subsequently insulating a sheet metal roof. In contrast to, for example, insulation between the rafters under tiles, an abutting and complete filling under the roof sheet leads to sweating. It can happen that the thermal insulation works perfectly in winter and in summer cascades of condensation water wet the insulation layer or water the attic.

Decouple fastening and contact points

When a roof is covered with sheet metal, all the connections between components form the decisive challenges for the insulation as a whole. Extensively designed and properly placed appropriate insulation layers can be massively "leveraged" in their effect by cold, sound and heat bridges. The following practical principles and physical phenomena must be observed:

  • Cold, sound and warmth propagate through "conductive " connections. Fastening components, rivets and screws must be decoupled
  • It is decoupled by interrupting a continuous material. Rubber-coated anchors and fastening pins are included, as are rubber or plastic sleeves
  • Cold and warmth can be kept out, dampened and insulated by air flow. It gives sound the opportunity to not only "physically" reproduce itself, but also through the air. Sound-absorbing inserts and mats, for example under the sheet metal above the rear ventilation duct, help here.
Tips & Tricks Let the roofer of your choice explain to you how to deal with the complex challenges and interactions between cold, noise and heat. He should be able to explain his procedure to you in understandable words.