As the first layer of insulation to be laid between the rafters, it is worth using large-size MEGAROCK or TOPROCK panels delivered in a rolled form.. With sections of length 2,5 – 6 m pieces are cut about 1 – 2 cm longer than the clear distance between the rafters. Such an allowance and elasticity of MEGAROCK or TOPROCK boards, obtained thanks to tangled fibers, they allow the use of frictional forces and the independent maintenance of the thermal insulation cut between the rafters. Warming the space between the rafters is not enough, to get an energy-saving attic. Therefore, a second layer of insulation is used, placed under the rafters, between the elements of the steel grate (e.g. made of U-profiles attached with hangers to the bottom of the rafters). Wall coverings are screwed to the grate, e.g. plasterboard – in dry rooms (e.g. bedroom, living room, corridor).
Warming thickness, necessary to obtain an energy-saving attic of the house is min. 22-25 cm (depending on the product) and is greater than the height of typical rafters. This is one of the reasons why two layers of mineral wool insulation are used, laid between the rafters and under them. This solution eliminates longitudinal thermal bridges, which rafters are, roof trusses or tongs of a wooden roof truss. In addition, their three-sided cladding with non-flammable Rockwool stone wool protects them against the effects of fire.
ROCKMIN or SUPERROCK panels should be used as the second layer of insulation – they are placed between the bottom of the rafters and the attic cladding, e.g. plasterboards or paneling. The grate moves below the rafter bottom, most often by 5 do 12 cm, using steel hangers or wooden blocks (you can also do more, depending on the length of the steel grate hangers or the thickness of the wooden blocks). Thanks to this, energy-saving insulation in thickness can be obtained 30 cm and more.
Due to their weight, TOPROCK and SUPERROCK boards with appropriately selected thickness perfectly absorb sounds from rain or hail, falling on the sheet metal covers, thus improving the acoustic comfort of attic rooms.
Attic insulation can be arranged at any time of the year. Particular attention should be paid to all corners and bends of the roof as well as wall connections with roof slants. Insulation of the attic slope should be, first of all, "continuous" – should be continuously combined with wall insulation (contact at the wall) and the attic ceiling. Accuracy of assembly – tightness at the joints of the plates – is obtained by pressing the plates together, using the elasticity of mineral wool. This way, thermal bridges at the plate joints are eliminated. An ordinary sharp knife is used to cut mineral wool products, keeping equal, smooth cut edges.
It is impossible to perform thermal insulation with ordinary mats working alone – these inconveniences are avoided by insulating with MEGAROCK or TOPROCK boards. The number of works on MEGAROCK or TOPROCK insulation is kept to a minimum – there is no need to use additional fastening of the thermal insulation with a rope to the rafters, because these plates can stay between them on their own. Their anti-gravity properties increase with the thickness of the plates, and decrease with increasing span between rafters. The amount of waste is also limited, because boards of any and required width (resulting from the spacing of the rafters) is obtained by cutting them to the required size – we cut as much from the roll as needed.
Always remember to properly ventilate the usable attic. It will be ensured by a highly vapor-permeable roof membrane either – in slopes with full boarding or initial covering foil (FWK) unobstructed ventilation gap of height 3-6 cm.