Heat loss in the house

Heat loss in the house

Heat loss in the house: how to eliminate the heat loss of a building. Do-it-yourself interventions and thermography.

In winter and especially in areas of Italy where the climate is more rigid, it is important to reduce the flow of heat exiting the building.

The components of the building envelope that causeheat lossthey are different, we are talking about windows, doors, chimneys, ventilation systems, shutter boxes, entry of pipes (water and gas pipelines), electrical sockets… but also perimeter walls and roof. To counteract thethermal dispersionswe should block any air infiltration by eliminating the so-called drafts. For do-it-yourself interventions to remove air infiltrations, I refer you to my guide article "how to eliminate drafts". On this page we will focus on how much the bills are chargedheat loss of a building.

Calculation of the thermal needs of a house

In Italy, thecalculation of the heat requirementof a building is governed by the UNI 7357 - 74 standard and by Law 10 of 1991. In calculating the heat requirement of a house, the role ofthermal dispersions. By thermal dispersion we mean the flows of hot air leaving the house during the winter and the flows of cold air leaving the house during the summer. Thermal insulation can lower the costs associated with winter heating and summer cooling.

In the article dedicated to how to calculate the power of a stove, we have already explained, broadly speaking, how to calculate the heat requirement of a building by providing you with a coefficient that can also take into account the heat loss of your home. When sizing a heating system, be it pellet or gas, it is essential to understand whenheat lossmake the appliance inefficient.

Calculate the heat losses

Thecalculationtheory of heat dispersion is not at all easy to apply in a domestic environment. The variables are many and oneformulageneral is not enough. It would take an ad hoc formula designed for each room, from the underground to the internal ones of the house, without mentioning the thermal gradient (temperature difference between the internal and external environment) which is different for each climatic zone in Italy. Another crucial factor is the degree of insulation of the walls, the year of construction of the building, the conditions ... In short, those looking for aformula for calculating heat lossescan only find something very uncertain.

Forcalculate the heat lossesit would be better to rely on thermographic analyzes of buildings. A thermography can detect theheat loss in the houseby recording the radiation (in the infrared field) emitted by the building envelope.

There is a correlation between radiation in the infrared field and temperature: the amount of radiation emitted increases in proportion to the fourth power of the absolute temperature of an object as specified by Stefan Boltzmann's Law.

To make a thermography, a device called a “thermal imager” is used; to make an illustrative comparison, the thermal imager is like a camera equipped with special sensors capable of detecting the surface temperature of the bodies and making it readable in a color map. The color map will tell us exactly where the files are locatedheat loss in the houseand, based on the findings, it will give us a concrete idea of ​​the extent of the heat loss recorded.

Unfortunately, a thermal imager is not a cheap device, so for the temography we either decide to act on our own and buy a thermal imager (costs start from 200 euros up to over 1000 euros) or we choose to rely on a technician who can perform the measurements for us. To get a concrete idea of ​​the prices and operation of thermal imaging cameras, please refer to the useful link below.

Useful link from Amazon: thermal imaging cameras, prices, models and performance

Heat losses, how to eliminate them

For do-it-yourself interventions, we invite you again to read the guide article entitled how to eliminate drafts. For more concrete interventions it will be necessary to rely on specialized companies.

For example, in the case ofheat loss from the roofand base, it will be necessary to apply a layer of insulation (at least 10 - 20 cm) directly above the slab or, in the case of an attic, there are insulating materials applied toinsufflation. Insufflation is also useful in the case of walls with cavity (where an insulating foam is inserted).

Video: Heat Loss In A House (January 2022).