The idea behind Martom hybrid doors is to intelligently combine different materials to achieve optimum performance. This means making use of their advantages while at the same time eliminating the disadvantages. There are many types of exterior doors on the market. The most popular are wooden, aluminium, steel or plastic doors. All these materials have advantages, but also disadvantages, which translate into the properties of the door and its price.
Steel offers great mechanical properties such as stiffness and strength. Compared to aluminium and PVC, it has low thermal expansion. It is a much better insulator than aluminium. It is available at a reasonable price.
Aluminium is a lightweight and weatherproof material. Unfortunately, it has two major flaws – it conducts heat very well and suffers from high thermal expansion. In order to neutralize these disadvantages, special technological solutions are needed, which further increase the production costs.
Wood as a structural material has a number of advantages – it is warm, light, stiff and has very low thermal expansion. Wood has a single, but serious flaw – it is not resistant to weather conditions and therefore requires burdensome and expensive maintenance.
PVC is a warm and lightweight material. Unfortunately, very high thermal expansion and low stiffness make it necessary to reinforce door profiles with thick steel sections. This results in a significant increase in the weight of the leaf and a deterioration in its insulation properties. Relatively high manufacturing cost.
Wood is used to make the core of the wood/steel thermal frame and the frame of the leaf. This ensures excellent insulation, thermal stability, stiffness and lightness of the structure. To protect against weather conditions, the wood is covered with sheet metal, which provides additional stiffness and improves mechanical properties. The frame can also be made of aluminium profile with a thermal pad of up to 90mm in thickness. Hybrid technology enables the production of doors with a unique thermal insulation of Ud=0.63 W/m2K, and at the same time it ensures a very high class of burglary and fire protection.
Martom’s hybrid technology enables production of doors with a coefficient of Ud 0.63 which are intended for passive houses. Doors with this coefficient belong to the absolute elite of energy-efficient doors.
The tightness of the door depends on the stiffness of the leaf. If the door leaf deforms, the door loses its insulating properties. Sheet steel is very rigid (Young’s modulus is three times higher than for aluminium), which allows it to withstand heavy loads. The injected PUR foam has excellent adhesion to the sheet metal and together both materials form a single structural element. As a result, Martom hybrid doors are extremely airtight, dent-proof and durable.
Martom offers a wide range of special doors – doors with burglary resistance class RC2, RC3 and RC4, doors that can withstand fire and at the same time provide smoke resistance for 30 and 60 minutes and doors that have a sound insulation factor of up to 42dB. Few companies producing doors offer special doors with such a high level of protection.
A great advantage of Martom hybrid doors is their resistance to weather conditions. They do not deform under the influence of temperature and moisture. They are resistant to UV radiation, heat and frost. They do not corrode. They do not require tiring and expensive maintenance or painting.
The leaf sheathing is covered with a special laminate made of the highest quality PVC, identical to the PVC used for windows. This laminate is very durable and has a high resistance to scratching. A special coating with low adhesion makes the door very easy to clean with the simplest agents – water and washing-up liquid.
A wide range of colours, a variety of patterns, glazing and decorative finishes and accessories make Martom’s offer meet the expectations of the most demanding and original customers.
Martom’s hybrid technology provides excellent technical performance. It has one more big advantage – relatively low production costs. Therefore, compared to other doors with similar properties made of wood or aluminium, the prices of Martom hybrid doors are very affordable.
Any technology can produce excellent doors with superb parameters. However, a very big advantage of Martom hybrid technology is that doors with excellent parameters can be offered at an attractive price.
0.16 – 0.22
Across fibres
0.30 – 0.40
Along fibres
17 – 50
160 – 250
0.17
0.03 – 0.045
EPS
0.032-0.038
XPS
0.025 – 0.035
The λ-factor determines the insulating properties of the material. The lower the coefficient, the better the insulator the material is.
The comparison shows that wood and PVC are very good insulators among construction materials. Definitely the worst insulator is aluminium, which is why aluminium profiles have a multi-chamber structure with special thermal pads, which unfortunately significantly increases costs. Materials used as thermal inserts for the leaf offer insulating properties many times better than construction materials, therefore doors manufactured in all technologies have leaves filled with foamed polystyrene or even high quality PUR foam.
α = 4
α = 12
α = 24
α = 52
Coefficient of linear expansion α
An important feature of a good door is its thermal stability. The surface of a dark-coloured door, if it is exposed to the sun for a long time in hot summer days, can heat up to 70°C. In cold winter days, on the other hand, the temperature can drop to -35°C. Materials with high expansion at such large temperature differences can warp, lose tightness and in extreme cases even prevent the door from being opened.
Very high thermal expansion is characteristic of PVC and aluminium. For PVC profiles, a suitable reinforcement with a steel profile is therefore necessary, while for aluminium profiles, special compensating solutions are used. Wood is very stable.
E = 9 – 13 GPa
E = 210 GPa
E = 70 GPa
E = 2,8 GPa
Young’s modulus E
Loss of tightness causes doors to lose their insulating properties since temperatures can be freely exchanged through leaks. The door tightness is determined by the stiffness of the leaf. The stiffness is determined by the Young modulus. This parameter is used to determine the stress levels at which deformation of a given element will occur. The higher the Young’s modulus is, the more force is needed to bend or dent the material.
Our list shows that in order to bend e.g. a steel sheet, three times as much force is needed than with an aluminium sheet of identical thickness. This parameter also translates into the durability of screwed-in elements such as hinges or screws. Therefore, anti-burglary and fire doors are very often made of steel components.
Moisture
bending and twisting, swelling, rotting
UV radiation
greying and deterioration
parasites, woodworm, fungi, moulds
required at least every 5 years
Moisture
galvanised and veneered sheet metal – high resistance
fading of colour
fading of colour
washing is sufficient
Moisture
high resistance
fading of colour
full resistance
washing is sufficient
Moisture
full resistance
fading of colour
full resistance
washing is sufficient
The λ-factor determines the insulating properties of the material. The lower the coefficient, the better the insulator the material is.
The comparison shows that wood and PVC are very good insulators among construction materials. Definitely the worst insulator is aluminium, which is why aluminium profiles have a multi-chamber structure with special thermal pads, which unfortunately significantly increases costs. Materials used as thermal inserts for the leaf offer insulating properties many times better than construction materials, therefore doors manufactured in all technologies have leaves filled with foamed polystyrene or even high quality PUR foam.