R'BULL project in Morzine

A chalet does not have the same needs as a lowland house

The gap between inside and outside temperature is larger there, for longer. Every insulation defect therefore costs more, and above all more often, which makes the continuity of the barrier more decisive than its stated value.

The roof, the main item

At altitude, snow covers the roof for part of the winter and changes the exchanges. What counts on the inside stays the same: the warm face must be closed, continuous and protected from air movement.

Intermittent occupation

Many mountain homes are used only a few weeks a year. An envelope that limits losses allows an economical frost protection setting to be held between stays, which represents most of the annual consumption.

Summer, forgotten in the mountains

Under a dark roof facing due south, the loft gets very hot during the day even at altitude. A reflector then works the other way round and improves comfort in the rooms under the slope.

The constraint of the job

Sometimes difficult access, a short working season, tradespeople in high demand. A light product delivered in rolls and fitted without heavy equipment fits those constraints better than a solution requiring significant logistics.

What can be checked afterwards

The surface temperature of the ceiling, measured on a cold day. It is the only simple indicator that says whether the work produced the expected effect, and it needs nothing but an infrared thermometer. A gap of two or three degrees between ceiling and walls signals a badly closed plenum, before the bill even says so.

Summer behaviour is set out on the thin insulation under roofs page, and the product on its data sheet.