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The device roof insulation

Features of production and use, economic aspects of the application.
 
The device roof insulation Currently, the construction industry the most widespread mastic and roll roofing. The grounds are carrying roll roofing, monolithic or prefabricated slabs, as well as different types of screeds (cement, sand, etc.) arranged on top of the insulation layer of the roof.
Often in practice carrying out roofing works raises the question of the choice of material and insulation layer of the roof itself, the web material during the repair work. Often the old roof does not meet the modern requirements of building heating engineering. Therefore, the standard problem of replacing the old waterproofing layer is added, and the need for a range of works to improve the thermal performance of the roof.
 
We note that the carrying out of repair work in the roof of the exploited buildings in dense urban areas is associated with considerable difficulties. Increasing the thickness of the insulation layer of the roof repaired to improve thermal performance, corresponding to modern requirements of energy saving, it requires a variety of activities.
 
  Material insulation layer repaired roof must meet a number of requirements:
 
·                           The low density of the material. The increase in the thickness of the insulation layer increases the load on the bearing elements of the building. It is desirable to use a material of low density (specific gravity), which will increase the load on the bearing elements of buildings within an acceptable range. If the weight of the heat-insulating layer is greater than the carrying capacity of the power elements of the building, you want to work on the construction of additional power structures, which negatively affects the total cost of repairs.
 
·                           The device roof insulation Low thermal conductivity. It is desirable to use a material with high resistance to heat transfer. The lower the conductivity of the selected material, the smaller the thickness of the insulating layer of the roof. Accordingly, to reduce the consumption insulation material, as well as the cost of transportation, delivery and installation. So, guided by the norms of thermal protection of buildings on the construction SNIP 23-02-2003 walling in the climatic conditions, we can demonstrate the possible economic impact of replacing the insulation layer of expanded clay in the sand on the expanded clay polystyrene density of 300 kg/m 3 . To meet the requirements of SNIP 23-02-2003 using keramsit (D-1800) require the organization of the thermal insulation layer thickness of at least 1.7m (coefficient of thermal conductivity in dry condition & lambda; = 0.66 W/m * a C) .   At the same time, the use of polystyrene density D-300 will reduce the thickness of the insulation layer up to 25 centimeters! The ability to reduce the thickness of the insulation layer, while maintaining the required energy savings, due to the difference of thermal conductivity materials. Since the thermal conductivity of expanded clay on the expanded clay sand in the dry state 0.66 W/(m * a C), concrete gravel 1.51 W/(m * of C), and polystyrene density of 300 kg/m 3 0.085 W/(m * a C)!  
Thermal performance polystyrene
GOST 51263-99
Table E.1

 

 
 
Odds
Calculated mass
Estimated coefficients
 
 
coefficient
the ratio of moisture in the
under operating conditions
Mark on average
Specific heat capacity,
thermal conductivity in the
material,%, under conditions
thermal conductivity,
paropronitsa
density
kJ/(kg & times; & deg; C)
dry state,
Operation
W/(m. & Deg; C)
bility mg/(m & times; h & times; Pa)
 
 
W/(m & times; & deg; C)
A
B
A
B
(A, B)
150
1,06
0,055
4
8
0,057
0,060
0,135
200
1,06
0,065
4
8
0,070
0,075
0,120
250
1,06
0,075
4
8
0,085
0,090
0,110
300
1,06
0,085
4
8
0,095
0, i05
0,100
350
1,06
0,095
4
8
0,110
0,120
0,090
400
1,06
0,105
4
8
0,120
0,130
0,085
450
1,06
0,115
4
8
0,130
0,140
0,080
500
1,06
0,125
4
8
0,140
0,155
0,075
550
1,06
0,135
4
8
0,155
0,175
0,070
600
1,06
0,145
4
8
0,175
0,200
0,068
Regulated physical and technical properties of concrete
 
GOST 25485-89     Concrete cellular

 

 
Type
 
Mark
Factor
 
Sorption humidity of concrete,% no more than
Concrete
concrete on Wednesdays & shy; her flesh-of
thermal conductivity-ness,
W/(m · & deg; C), not more concrete in dry
paropronitsa-bility,
mg/(m · h · Pa), not less, concrete manufac -
at relative humidity of the air, 75%
at relative humidity of the air, 97%
 
 
state of prepara-
tovlennogo
Concrete made
 
 
in the sand
on the ash
in the sand
on the ash
in the sand
on the ash
in the sand
on the ash
Thermal -
D300
0,08
0,08
0,26
0,23
8
12
12
18
insulating
D400
0,10
0,09
0,23
0,20
8
12
12
18
 
D500
0,12
0,10
0,20
0,18
8
12
12
18
Constructive -
D500
0,12
0,10
0,20
0,18
8
12
12
18
translationally-tep -
D600
0,14
0,13
0,17
0,16
8
12
12
18
loizolyatsi -
D700
0,18
0,15
0,15
0,14
8
12
12
18
onny
D800
0,21
0,18
0,14
0,12
10
15
15
22
 
D900
0,24
0,20
0,12
0,11
10
15
15
22
Constructive -
D1000
0,29
0,23
0,11
0,10
10
15
15
22
insulating
D1100
0,34
0,26
0,10
0,09
10
15
15
22
 
D1200
0,38
0,29
0,10
0,08
10
15
15
22
 
·                          

The device roof insulation

 
High (enough) the mechanical strength. The ability to reduce curing time.
 
Work on the unit or repair of roofs can be divided into two phases: laying the thermal insulation layer and often performs the role of tie-base for mounting rolling waterproofing materials, and directly the installation of roll, roofing materials.
Thus, the prepared surface is laid insulation layer material. After working for the care of maturing concrete   and aging of concrete, enough to set the necessary strength (at least 1.5MPa), start laying the web material.
Naturally, it is desirable to reduce the time between work on the device of the insulation layer and the laying of waterproofing material. Works on care of maturing concrete (keramsit polystyrene foam concrete) include protection of concrete from direct sunlight and wind (shelter tie polymer films, wet sawdust, etc.). Wetted surface screed to prevent cracking of the material. When using materials based on Portland cement should be watered with water screed maturing within 7 days followed by mandatory cover, which prevents rapid loss of moisture the upper layers of the screed.
After a set of material ties necessary strength, you can start laying the roll materials. To reduce the curing time, the screed-base heat-insulating layer may be used plasticizers for concrete and mortars (GOST 24211-03). Plasticizer concrete, being a complex product based on sodium salts, significantly accelerate the curing of concrete in the first two days of normal hardening by 20-45%. The use of additives can significantly reduce water consumption (20%), increases udobnoukladyvaemost concrete significantly increases treschenostoykost and water resistance of concrete (polystyrene foam, etc).
 
·               Low weight ratio of moisture in the material.
Water absorption of the material warming layer is an important indicator, largely determines the operational parameters of the roof.
A material having a high water absorption, in any case can not be recommended for the device insulation layer of the roof. When using concrete lightweight aggregate (expanded clay, polystyrene) and foam is recommended repellent additives concrete. Application of waterproofing additive allows to obtain a material with a weight ratio of water no more than 5%.
The most frequently used as the material of the thermal insulation layer of roofing claydite has a weight ratio of moisture in the material of 10% (for conditions B), while the polystyrene density of 150 to 600kg/m 3 of not more than 8%.
·               Udobnoukladovaemost material.
The ability to use means of mechanization of concrete work.       The ability to use different types of concrete pumps to supply the material to the place of installation.
Udobnoukladovaemost material and its uniformity - an important component of the success of the concrete work in the repair of (unit) of the roof. Uniformity (nerasslaivaemost) of concrete is achieved by careful dosage of components, mixing quality and the overall mixture of water-holding capacity.
When used as a warming layer of material-tie   polystyrene or foam should focus on choosing the type of pump concrete, aggregates and concrete work mechanization (screeds, compactors).
For the organization of supply pressure foam concrete mass concrete and lightweight aggregate is desirable to use pumps do not create excessive line pressure. Pressure supply of foam and polystyrene can be recommended screw pumps (gyratory) Pneumosuperchargers different capacity.
  If you use mortar-diaphragm plunger type is often observed bundle of foam concrete solutions and lightweight aggregate concrete (polystyrene). This is due to the creation of a high pressure (do25Atm) during the course of the working body of the feeding-mortar diaphragm plunger type.
 
Udobnoukladyvaemost a mixture mainly depends on the size distribution and the amount of water (wet concrete). The mobility of the concrete (foam) is assigned to   based on the particular concreted surfaces, the degree and nature of reinforcement (if applicable), and the slope repaired or erected roof. Also, when choosing a mobility concrete (foam concrete) mixture should take into account the ways of transportation and packing.
It should be noted that the repair of the roof, using modern materials teploenergosberegayuschih advisable to organize the preparation of the material warming layer in the vicinity of the work area.
Preparation of foam or polystyrene of different densities it is easy to organize directly on the construction site, thus reducing transportation costs associated with the delivery of the material to the point of use. Note that the delivery of pellets of expanded polystyrene in the production of polystyrene having a bulk density of from 8 to 30 kg/m 3 and takes up 80% of the polystyrene mixture, a task simpler than the delivery of sand and cement with a density of more than 1000 kg/m 3 ! For the preparation of non-autoclaved aerated concrete (cellular concrete) are different blowing agents, with an average consumption of foaming agent about 0.5-1kg per cubic meter of foam. After the introduction of a foaming agent in a cement-sandy solution is an increase in volume due to the active porization mixture. The volume can be increased to 2.5 times or more! As a result, significantly reduces the amount of raw materials (cement, sand) of imported to the building site. There is a significant savings of binding components of the mixture and inert, reducing transportation costs, reduction of the total volume of repair work.
 
 
 
 
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