External wall Information

The  Home Valley Group standard exterior walls are prefabricated timber frame closed panels units made from treated pine Class C24 and are PEFC approved with studs at  standard 625mm centres. All timbers are treated with preservative as required by British and European  Building Regulations. They are completely filled with isover or equivalent standard  Rockwool insulation, sealed with a vapour control barrier and then closed on the inside with 12-18mm gypsum plasterboard. On the outside a 15mm cement based particle board encloses the timber frame. In addition either, 100mm of Expanded Polystyrene Insulation (EPS) and a finish coat are applied in the factory or on site or 50mm EPS with a waterproof breather membrane is used if external cladding will be added (brick, timber or clay tiles). The maximum panel length is 13m and the maximum height is 29.50m. These measures are determined by the type of transportation we can use.

The Home Valley Group external walls can be used with various types of cladding:

  • Render, applied in factory or on site, depending on the customers choice and dependent if it is a Passiv House
  • Wooden cladding (installed in factory or on site depending on the independent design requirements)
  • Rain screen cladding systems like Trespa or Reynobond can be fixed in the factory
  • Brick or stone finish (on site only)
  • Others: Brick slips, clay tiles or other rain screen cladding systems can all be fixed on site.

 

MODEL OF A CROSS SECTION OF THE EXTERNAL WALL ELEMENT  USING HIGH INSULATON PROPERTIES: 250 mm

       Brick Or  render face             

This wall is designed for the climatic conditions in most of Europe  and the middle east and offers excellent accoustic and theremal insulation properties giving a quality of life living second to none:

Structure of the 250 mm wall:

  • Silicone coating
  • Basic plastering with mesh
  • Facade insulation boards EPS - 100mm
  • 10 mm gypsum fiber board
  • 60 x 120mm beam structure filled with mineral wool 120mm - with a thermal conductivity λ = 0,040
  • membrane - steam barrier
  • 10 mm gypsum fiber board
  • Total thickness of 250 mm.
  • Coefficient of thermal conductivity U = 0,19 W/(m2K)
  • The wall is diffusive open / breathable / from inside to outside
  • At the present construction of the wall no condensation can appear
  • Outside temperature -10 ° C and internal temperature of the building from+ 20 ° C, the temperature of the inner surface of the wall is +18, 7° C.

INFORMATION ON Heat conductivity of building materials
The symbol λ in modern construction means the specific thermal conductivity of each material used. This parameter characterizes the ability of any material to transfer heat energy in the form of heat. The specific conductivity is a constant for each type of material. The lower this number is the lower is the speed of transmission i.e. higher is the thermal insulation capability.

 

Examples for the number of thermal conductivity λ, of different construction materials:

Material

λ W/(mK)

Steel

48 - 58

Concrete

2,1

Granite

2,8

Glass

0,76

Brick

0,5 - 1,4

Render

1,4

Mineral wool

0,032 - 0,050

EPS (Styrofoam)

0,035 - 0,050

Wood

0,09 - 0,19

Cork

0,035 - 0,046

Iron

80,2

 

Very often, on the layout of construction materials is indicated their number of thermal conductivity - λ. We hope this information will help you understand what it means and its effects:


INFORMATION ON Heat transfer coefficient - U

In construction physics U-is used to describe the thermal conductivity of individual multilayer elements. In most cases, the various walls, vertical, horizontal and sloped elements consist of separate layers with different thicknesses and materials, so it is necessary to determine the thermal conductivity of each element depending on the characteristics and thickness of the layers.

This coefficient is calculated based on the numbers of thermal conductivity of the different layers, depending on their thickness on sq m. The lower the value, the better the insulation of the element is.

Examples: different types of multilayer elements and their coefficient U:

Types of multilayer elements

Thickness

U value

External walls - concrete, no insulation

25

3,3

External walls - brick, no insulation

25

1,26

External walls - brick with 5 cm EPS

30

0,46

Outer wall - concrete with 5 cm EPS

30

0,65

Timber frame construction with 22 cm insulation

25

0,19

Low-energy wall with 46 cm insulation

49

0,09

 

For More Information contact us now on:  This email address is being protected from spambots. You need JavaScript enabled to view it.